Web Hosting
Web Hosting Web Hosting is a service which makes a site available from the Internet.

Web Hosting is a service which makes a site available from the Internet. It provides a physical place for your site (server) and Internet connection, also it may provide DNS services. Hosting companies differs from those who own huge datacenters to the small ones who rent couple of servers somewhere.

How to choose a hosting? You should pay attention to several important things: features, price, support and uptime.

Features include disk space, database usage, bandwidth, monthly traffic etc. Requirements totally depend on your site. It is clear that personal page has different requirements than a well-known online market.

Price. You may even find completely free hosting, just look if the service satisfies your needs.

Support. How long does it take to solve a problem with your site? What is an avarage response time? Your site is down for a week, and noone cares - is that possible?

Uptime - what is actual running time of the site.

Reliable hosting is very important for business. Using website monitoring services may help to evaluate the hosting service and check how often do the problems really appear.

  • CM.Glossary.Uptime
  • CM.Glossary.Downtime
  • CM.Glossary.WebsiteMonitoring
  • CM.Glossary.DNS
more glossary
"

Very usefull service, helps us to monitor activity of our sites.

"
- A.
Monitoring domain and SSL certificate expiry dates

▶ Monitoring domain and SSL certificate expiry dates.

▶ How to activate the SSL certificate monitoring tool and domain monitoring settings?

▶ It takes only several minutes with HostTracker

So many domain names are lost in this fashion. The domain name holders have their names taken away by others, simply because they miss the renewal alerts and they do not notice when their domains are not running the show anymore. Although the whole system for domain name holders is not very practical or sensible, reality confirms that dropping a domain name is a significant problem nowadays. Anyone who holds a domain name is very much prone to losing it, ranging from big corporations, like Microsoft, to small private firms. Trying to solve this problem, HostTracker has developed utterly useful tools that highly increase the chances to reach 100% uptime.

Controlling tools

Registrars are obliged to keep the registered name owner always updated on the status of a domain and must notify of the impending expiration at least two times. One of these notifications must be sent about one month prior to expiration and one must be sent about one week prior to expiration. But “In theory, theory and practice are the same. In practice, they are not”. That’s why a lot of very bad things keep on happening. For instance:

  • Alerts go to the spam folder;
  • Responsible employees are taking time off work;
  • Or just there is something more important that should be solved just at this moment and the domain renewal is put off for the better times.

Problems like these occur very often.  Moreover, when we face them - no one can recall the timing of the registration, the timing of payments, the cards from which the money was written off etc.

Are you getting the idea that it’s truly important to pay attention to this stuff? Use HostTracker tools. The service will monitor your domain/SSL certificates for many different status changes, such as when a domain becomes registered, when it drops and becomes available, when it's renewed and everything. You can enable automatic summary reports that are emailed on a daily / weekly / monthly basis (or at any interval you choose). The reports can include renewal dates of registration and any other useful information and can be sent, for example, via SMS, email or a Skype. These instruments are also fully configurable and can be used together or separate with regular uptime checks.

Domain Monitoring Service Settings

Applying domain monitoring settings takes several minutes:

simply enter the domain name. You can click on "Add list" to monitor more than one website. You may also configure additional options by clicking on "Subscriptions" bar:

  • “Up” - the domain renewal notices are emailed one month, 7 and 3 days prior to expiration.
  • “Down” - you are notified that your domain name has already expired.
  • “Repeat” - you receive alerts every day until you renew the domain name.

Put tick marks next to the contacts of people, who should be informed in case of any problems.

If you want to be notified not only by email, but also by other messengers (Skype, Viber, Hangouts, Telegram), add them in the "Add Contact" bar or in the "Notifications" menu on the main page screen.

How to activate the SSL certificate monitoring tool

Since Google announced that they’re going to be using whether or not a server uses SSL as a ranking signal, the number of people interested in purchasing SSL certificates has skyrocketed. Why are SSL/TLS certificates so beneficial? 

The idea of using SSL/TLS certificates is crystal clear, as it is a type of encryption used for securing web sessions. HTTPS keeps both your websites and your customers' personal information private and secure. As when a SSL certificate is used, the information becomes indecipherable to everyone besides for the server you are sending the data to. This protects it from "domain slamming", "email phishing" attacks and other harmful activities.

Therefore, it is vital not to miss SSL/TLS certificates expiry dates. Both domain monitoring and SSL monitoring instruments are operating alike and have the same configuration, which includes:

  • Sending renewal notifications 30, 7, and 1 days prior to certificate expiration.
  • Sending instant reports when security certificate is becoming “off”.
  • Reporting daily about the necessity to renew the SSL/TLS certificates.
  • Selecting groups of contacts who can be informed in case of a crisis/emergency.

With activating the two monitoring functions in the Business or Enterprise packages, or in a trial mode, you’ll be always aware of the certificate or domain expiry dates. Or at least, in case of unintentional domain losses, you will be eager to know the reason when, why and how it has happened and sort out the problem.

HostTracker is client-focused

That’s why one of our founding principles as a company included remaining flexible and adaptable, as well as open to improving our service. As the technology world changes, we’ll be ready to make quick, minute adjustments, add new tools and implement new features to improve our product.

Many of our features and enhancements are available online and have been minted due to the customer requests. Therefore, we are looking forward to hearing your feedbacks, suggestions and new creative ideas.

 

more blog
Thank you for feedback!
 
Sign In
Sign Up
Prices & packages
Our monitoring network
Home > Blog
How to monitor availability of any web site?

The main feature of HostTracker monitoring service is the regular checks of web sites with monitoring intervals from 1 minute. Moreover, the HostTracker’s dedicated global monitoring checkpoints network currently includes more than 140 servers all over the world.

The main feature of HostTracker monitoring service is the regular checks of web sites with monitoring intervals from 1 minute. Moreover, the HostTracker’s dedicated global monitoring checkpoints network currently includes more than 140 servers all over the world.

Each test is simulating the visit of a real users. If this imaginary visitor is able to load the site – everything is ok, otherwise – the site is revised again by a certain algorithm (just to be sure). Then, if an error was identified, it is recorded in the database and the notification of unavailability is sent. This is the easiest way to check the site’s availability. If you are interested, HostTracker has a great deal of more sophisticated tests to offer.

Types of tools for web accessibility evaluation

Here are some quick checks you can start with immediately that will move your web site toward better accessibility. It is worth noting that these checks support different protocols.

For example:

  • HTTP - this is an ordinary request, which is obtained from the user's browser.
  • Ping – helps to test site or server network connectivity. 
  • TCP-port - tests the site-to-application connectivity.
  • Database Check - a health check which can ensure that the web server can connect to the database and can also help in monitoring of other vital features. For those seeking a possibility to check the data on the page, there is a content check function. In this case, the virtual client is not just logging in, but also looking for the presence or absence of certain words and phrases. This feature helps you to detect whether some important section of the text has been lost. Moreover, it helps you to spot any mistakes on the page at once.
  • With HostTracker service you can also monitor the response and loading time of your web site. Furthermore, the corresponding data is being written to the inspection logs.

Armed with all these tests, you’ll be eager to collect extensive and thorough information about your web site. You’ll be entitled to know when, why and how did your web site stop working. For example, when the network, server or web site itself are down. Moreover, by using HostTracker, you can immediately detect when web site performance goes down and omit causing any inconveniences for your users. Or even more – you can easily recognize when some data isn’t regularly retrieved from the database. All these tools can help you pinpoint and rectify performance and speed issues with any publicly available web site. It, definitely, saves your time! And, in this case, downtime is small.

Interesting fact:

Almost all HostTracker’s customers are eager to reach 99% or higher uptime. By the way, the data from this service could be a good support in your future confrontations with hosting partner. Truly, many HostTracker’s customers have found a reliable web hosting partner or made him fulfill all promises and commitments according to the contract.

  • HostTracker provides options for monitoring the domain and SSL certificate expiry dates. This problem seems to be handled easily, as the registrar sends alert notifications, but history provides plenty of notification neglect examples.  Dropping the domain name is a widely spread problem. Actually, Microsoft has encountered it twice.
  • Also HostTracker is one of the best resources that can help to find out if your IPs or domains are on some SPAM-database (so called DNSBL). Apparently, if it seems that you're engaged in spamming or other unwanted online behaviour, your IPs or domain could get blacklisted and blocked. The blacklist usually contains email servers suspected of spreading spam or servers that have been infested with some nasty malware etc. 

Most Internet service providers and web servers use these blacklists to detect IPs linked to computers with pervading spam or unwanted activity. And the problem is: you can be blacklisted accidentally and be unaware about it. If it happens, your rankings will go down or disappear entirely. You can be truly innocent of any deliberate wrongdoing and still be on the list. For example, if you share your web hosting with someone unreliable. With this monitoring function you can be always aware if your company’s domain name is blacklisted and be ready to deal with it. You're likely to come across contacting the list by email or passing through some sort of automatic procedures in order to prove that you are not a robot when you’ll be trying to get off a blacklist.

HostTracker service settings

All above-mentioned checks teem with the wide variety of options:

  • Maintenance planning and scheduling – allows you, for instance, not to catch the errors during the server upgrade period.
  • Checks from a particular location- as outlined above, there is a huge network of global monitoring checkpoints, and it is possible to choose only regions with potential clientele:

  • Delay alerts – this option will postpone alert notifications for a specified time span; manage notifications in line with the importance of issues; control the life cycle of both alerts and their notifications.

As regards alert notifications option, clients will find themselves spoiled for choice. HostTracker provides notifications via e-mail, SMS and, by extension, via Skype, Viber, Hangouts and voice call. The most striking one - POST request. There is a possibility to send a request to a specific web server (e.g. to restart the web site automatically).

HostTracker service has an API, which allows pieces of software to interact. It is considered as a contract provided by one piece of computer software to another.

The next HostTracker’s advantage is that the service doesn’t require a lot of system resources (e.g. installation any client software). Almost all features are operating using cloud services, and can be configured with only HostTracker’s web site tools. And service settings, definitely, won’t take much time!

Generally speaking, the service is still being developed, as well as, the monitoring network expands, new tools pop up and so on. Considering new tools, they are being developed in response to the requests made by clients. Please don’t hesitate to contact HostTracker’s admins if you have any further suggestions about extra tools which yet aren’t provided by the service.

more
How to activate API for your Host-Tracker account

HostTracker API uses widespread XML and JSON formats. Interactions with API are made by HTTP methods GET, POST, PUT, DELETE, PATCH.

To activate API for your HostTracker account, one should write a request to ht2support@host-tracker.com, with the login specified.

Host-tracker API

API stands for "application programming interface". It is one of the features for HostTracker website monitoring service, which is implemented in preset list of HTTP requests and HTTP responses for maintaining and adjusting HostTracker features for your convenience. It provides possibility to develop applications which will automatically cooperate with HostTracker service, instead of manual adjustments via user interface.
HostTracker API uses widespread XML and JSON formats. Interactions with API are made by HTTP methods GET, POST, PUT, DELETE, PATCH.

To activate API for your HostTracker account, one should write a request to ht2support@host-tracker.com, with the login specified.

REST API description:

https://www.host-tracker.com/api/web/help.html

SOAP API description:

www.host-tracker.com/api/soap/v1/help.html

more
Tags: api
Domains: do they have afterlife?

Every year, millions of domain names are lost. What happens after domain expires? How long will your domain wait for you before someone grabs it? And how to omit this?  

Monitor your domains for any changes. You can keep an eye on the state of available domains which you like, but don’t forget your own ones too. There is a wide variety of services, like HostTracker, which provide an easy, efficient way to track any changes of domain’s state.

Domains: do they have afterlife?

Everyone may face the problem of losing the domain name. Every year, millions of domain names are lost. Mostly, it happens unintentionally, the owners miss the renewal notices for various reasons and they do not figure out that they are in the process of losing their prized domain until it is too late! In this article you will get to know about the most known examples of domain expirations. Moreover, we will see that big companies, such as Microsoft, Foursquare, Yatra, are also insecure to "the drop game". Additionally, you will find out how to keep the domain name if you forget to pay for domain renewal. How long will your domain wait for you before someone grabs it? And how to omit this?

How Microsoft lost hotmail.co.uk

One of the most striking examples of dropping the domain name ocured in 2003 due to what is called the collective negligence. In spite of the fact, that people were trying to check up on what was happening and somehow to deal with the problem, Microsoft behaved as a typical bureaucratic organization. It turned a blind eye to people inquiries. Despite being warned that it’s time for the domain renewal, Microsoft overlooked these notifications. Therefore, the domain was returned to the pool of available domains. Moreover, its mail service wasn’t accessible in England.

Luckily, the domain was grabbed at once. The new owner was so kind that tried to inform Microsoft immediately that they needed to re-register the domain and restore the service. Nevertheless, Microsoft didn’t seem eager to get their site back and ignored these messages. Microsoft realized the issue just when journalists contacted it.  Only then, the software giant reached a new owner of their domain. What is more, even after that, during a long period of time Microsoft had been stalling for time before the problem was sorted out. It seems that no one in the UK could deal with the problem, because only the central office was responsible for domain registrations.

Fortunately, hotmail.co.uk was regained. But still, Microsoft didn’t officially confirm that hotmail.co.uk had been dropped.

Only a registrar for all .uk domains shed light on this situation and born out that hotmail.co.uk had failed to be renewed despite being warned about the importance of the renewal procedure. Moreover, the registrar confirmed that the domain was snatched up by a private person. Apparently, all notifications via mail were ignored by the giant. It’s interesting that it wasn’t the very first time when something like that has happened with this company. In 1999, Microsoft had similar bad experience.

What happens after domain expires?

The procedure depends on registrar of the domain names. In addition, this procedure has changed many times over history. In this article we will be concerned with the most typical up-to-date procedure.

The first stage - the registrar shows loyalty to the client and gives extra time for domain renewal (grace period). Your grace period may take about from one to 2-3 weeks. This window can have a few deadlines - for example, a free update period, an additional fee etc.  When the domain is in a grace period where all services are shut off, it isn’t available for registration by anybody else.

The second stage - the auction. After the registrar is sure that the domain renewal hasn’t been done, he puts it up for auction. It's a registrar’s chance to bring in extra income- the domain can be auctioned off to the highest bidder.  Let’s be frank, it works- many domains are snapped up at auction. Let’s look at some of the most popular auctions:

Each registrar cooperates with only one of these auction services. Domain names are exclusive to one auction, as the sell-off can’t take place at two locations. How does the auction work?

To begin with, there is often the opportunity to place a backorder. For example, if someone is very interested in scoring your domain name. In this case, the buyer will get the notification about the expiration status of the target domain and, definitely, leverage this opportunity. It’s worth noting that during this period, domains can be included in backorder auctions, where another participant can bid on your domain name. Generally, an auction can consist of several stages, as well as, after the main auction can follow the closeout of least desired domain names.

In addition to this, there are such sites that collect information and provide it in a more convenient way. For instance, these sites will help you to discover that more than 3 million domains have expired for the last 10 days. Furthermore, you will realize that even expensive (costing up to $ 500K) domains can be dropped after a while.

The third stage - domain "death". The domain disappears, and it can be retrieved on a common basis. Unfortunately, it’s unlikely if a domain name has any marginal value, as well as, consists of unambiguous words and is well-promoted. If so, the domain will probably get purchased, as nowadays it is also kind of business.

Some extra good examples

In 2010, a well-known website Foursquare forgot to renew their domain name. Luckily, they noticed this in time and quickly sorted out the problem. Nevertheless, customers couldn’t reach the site during this period of time. At that time the internet was bombarded with these news, yet the company has taken the advantage from this situation.

However, sad examples do exist too. In 2012, a popular Indian travel site Yatra.com, with millions of visitors and huge income, dropped their domain. Therefore they lost not only money, but also their reputation, clients and the trust of their partners. Eventually, the domain has been restored. The company hasn’t been as successful since.
Such common experience has held almost everyone once in a while in their history, from banks to giant companies.  Actually, HostTracker had such experience too and it was the reason why we decided to write this article.

Web site monitoring service almost lost its domain

The truth is that host-tracker.com was almost lost despite having an instrument for keeping an eye for an expiration date and sending renewal alerts. Actually, this feature became HostTracker’s last resort, as all domains and sites are being monitored by HostTracker’s own monitoring system. In a manner of speaking, even though at that time the HostTracker company got the renewal alerts, everything seemed to be fine, as the auto-renewal was on. However, for some reason, the automatic payments didn’t pass through and the domain wasn’t renewed. To be honest, we are still not sure why did that happen, as their support could not explain the issue clearly. Luckily, we noticed the problem in time and solved it quickly.

To sum up:

  • Renew your domain in advance. In this case you might want to ask your registrar to set up your domain to auto-renewal in advance with your approval beforehand. Moreover, you will be notified in case of any problems.
  • Backorder does work. Just before HostTracker entered their grace period, someone had tried to contact HostTracker by mail to acquire the domain name. So pay attention to such things!
  • You would better not enter the grace period. Once the domain expires, it can be easily renewed at the regular price within a few days and HostTracker showed this. The disadvantage is that all customers will be greeted with the message that domain page isn’t available. You should never allow a domain to expire because working on recovering it can take a vast amount of time.
  • Monitor your domains for any changes. You can keep an eye on the state of available domains which you like, but don’t forget your own ones too. There is a wide variety of services, like HostTracker, which provide an easy, efficient way to track any changes of domain’s state. Check out the description of such HostTracker’s tools here.
more
Monitoring domain and SSL certificate expiry dates

▶ Monitoring domain and SSL certificate expiry dates.

▶ How to activate the SSL certificate monitoring tool and domain monitoring settings?

▶ It takes only several minutes with HostTracker

So many domain names are lost in this fashion. The domain name holders have their names taken away by others, simply because they miss the renewal alerts and they do not notice when their domains are not running the show anymore. Although the whole system for domain name holders is not very practical or sensible, reality confirms that dropping a domain name is a significant problem nowadays. Anyone who holds a domain name is very much prone to losing it, ranging from big corporations, like Microsoft, to small private firms. Trying to solve this problem, HostTracker has developed utterly useful tools that highly increase the chances to reach 100% uptime.

Controlling tools

Registrars are obliged to keep the registered name owner always updated on the status of a domain and must notify of the impending expiration at least two times. One of these notifications must be sent about one month prior to expiration and one must be sent about one week prior to expiration. But “In theory, theory and practice are the same. In practice, they are not”. That’s why a lot of very bad things keep on happening. For instance:

  • Alerts go to the spam folder;
  • Responsible employees are taking time off work;
  • Or just there is something more important that should be solved just at this moment and the domain renewal is put off for the better times.

Problems like these occur very often.  Moreover, when we face them - no one can recall the timing of the registration, the timing of payments, the cards from which the money was written off etc.

Are you getting the idea that it’s truly important to pay attention to this stuff? Use HostTracker tools. The service will monitor your domain/SSL certificates for many different status changes, such as when a domain becomes registered, when it drops and becomes available, when it's renewed and everything. You can enable automatic summary reports that are emailed on a daily / weekly / monthly basis (or at any interval you choose). The reports can include renewal dates of registration and any other useful information and can be sent, for example, via SMS, email or a Skype. These instruments are also fully configurable and can be used together or separate with regular uptime checks.

Domain Monitoring Service Settings

Applying domain monitoring settings takes several minutes:

simply enter the domain name. You can click on "Add list" to monitor more than one website. You may also configure additional options by clicking on "Subscriptions" bar:

  • “Up” - the domain renewal notices are emailed one month, 7 and 3 days prior to expiration.
  • “Down” - you are notified that your domain name has already expired.
  • “Repeat” - you receive alerts every day until you renew the domain name.

Put tick marks next to the contacts of people, who should be informed in case of any problems.

If you want to be notified not only by email, but also by other messengers (Skype, Viber, Hangouts, Telegram), add them in the "Add Contact" bar or in the "Notifications" menu on the main page screen.

How to activate the SSL certificate monitoring tool

Since Google announced that they’re going to be using whether or not a server uses SSL as a ranking signal, the number of people interested in purchasing SSL certificates has skyrocketed. Why are SSL/TLS certificates so beneficial? 

The idea of using SSL/TLS certificates is crystal clear, as it is a type of encryption used for securing web sessions. HTTPS keeps both your websites and your customers' personal information private and secure. As when a SSL certificate is used, the information becomes indecipherable to everyone besides for the server you are sending the data to. This protects it from "domain slamming", "email phishing" attacks and other harmful activities.

Therefore, it is vital not to miss SSL/TLS certificates expiry dates. Both domain monitoring and SSL monitoring instruments are operating alike and have the same configuration, which includes:

  • Sending renewal notifications 30, 7, and 1 days prior to certificate expiration.
  • Sending instant reports when security certificate is becoming “off”.
  • Reporting daily about the necessity to renew the SSL/TLS certificates.
  • Selecting groups of contacts who can be informed in case of a crisis/emergency.

With activating the two monitoring functions in the Business or Enterprise packages, or in a trial mode, you’ll be always aware of the certificate or domain expiry dates. Or at least, in case of unintentional domain losses, you will be eager to know the reason when, why and how it has happened and sort out the problem.

HostTracker is client-focused

That’s why one of our founding principles as a company included remaining flexible and adaptable, as well as open to improving our service. As the technology world changes, we’ll be ready to make quick, minute adjustments, add new tools and implement new features to improve our product.

Many of our features and enhancements are available online and have been minted due to the customer requests. Therefore, we are looking forward to hearing your feedbacks, suggestions and new creative ideas.

 

more
Escalations. Typical scenarios

As many people know, HostTracker is a sites efficiency monitoring system. One of its main functions is to notify the user of any problems promptly. The efficiency of the notifications and the acceptable level of “detalization” are important. If you send alerts at each “sneeze”, the person will not find the important information in this flow...

I was woken up by an SMS at three a.m.
My site dropped for three minutes, and it raised back itself.
But I could not go back to sleep.
True-life story

As many people know, HostTracker is a sites efficiency monitoring system. One of its main functions is to notify the user of any problems promptly. The efficiency of the notifications and the acceptable level of “detalization” are important. If you send alerts at each “sneeze”, the person will not find the important information in this flow.

We have provided several mechanisms that will help the right people to get the necessary notifications:

  • Separation of the notifications into several groups according to their criticality;
  • No notifications at short-term failures;
  • Report the problem to the manager promptly;
  • Report a prolonged failure to the administration;
  • Use the free alerts first – email, gtalk, and then the paid ones – SMS or phone call;
  • At the contact level – set the working time when this contact should receive the alerts.

There are three types of notifications:

  • The website has “dropped”;
  • The website is still “down”;
  • The website “rose

The “dropped” and “rose” are clear. The notifications “site is still down” are sent at each test fail, but only at the confirmed drops. The fails confirmation algorithm was described in the article “False alerts exclusion”

For each site-contact pair you may enable or disable the appropriate notification type. The setting can be located in the contact properties as well as in the general “matrix” at the “Notifications subscribtion” page.

Escalation and the notifications detalization level.

Suppose, two people are responsible for the site:

  • Administrator
  • Manager

Let's try to implement the following scenario:

  • In the event of a “drop” we want to send an email message to the administrator immediately;
  • If the site does not rise within 15 minutes, we send an SMS to the administrator;
  • If the site is “down” for more than an hour, then we send an SMS to the manager.

Adding the contacts for the users. While adding, draw attention to the “Notification Delay” window.

We appear to have three contacts with the following delays:

  • Administrator (email) – no delay;
  • Administrator (SMS) – 15 minutes delay;
  • Manager (SMS) – 1 hour delay.

According to this configuration the administrator will get all the failures notifications to the email, but SMS notifications will be sent only if the site is “down” for more then 15 minutes. The manager will receive only SMS about major failures lasting more than an hour. Setting up the contact working schedule

Suppose that one administrator can not cope, and we hired one more administrator. The first one works during the first half of the week, the second one works during the second half. Accordingly the notifications should be sent to the administrator “on duty” To set this scenario the window “Set the contact working hours” is used in the contact settings.

In this case the first administrator will receive the SMS notifications from Monday to Thursday inclusive. Additionally, you may divide the notification for different employees according to the time of day, for example appointing day and night administrators.

Conclusions: with the help of relatively simple mechanisms we may cover most notifications fine-tune user scenarios.

more
Host-Tracker under Windows Azure

Those, who actively involved with the Web, should know HostTracker, a company from Ukraine, which has been supporting one of the leading global web monitoring services since 2004. Its goal is to monitor site health and accessibility in near-real-time access. Using alert message system, HostTracker allows to reduce downtimes, to improve quality of service for users, to quickly localize troubles...

​Those, who actively involved with the Web, should know HostTracker, a company from Ukraine, which has been supporting one of the leading global web monitoring services since 2004. Its goal is to monitor site health and accessibility in near-real-time access. Using alert message system, HostTracker allows to reduce downtimes, to improve quality of service for users, to quickly localize troubles, and etc.

Architecturally, HostTracker includes a server-based hub, acting both as a data collector and control center, and a series of software agents, launched in various regions – typically using the equipment operated by major providers, hosters and affiliates. The geographically distributed architecture provides common system reliability and also allows collecting data in terms of access speed, bandwidth and other key performance characteristics on regional level – a critically important feature for the international business.

The first version of HostTracker, which is still functioning and providing services for tens of thousands of customers, was Linux based. Today, it is supported by nine control servers, located and organized in two DPCs on collocation principle, and few dozens of agents. Considering that the final objective of web monitoring is focused on increasing the uptime of client-based web resources – whereas 95% of HostTracker customers were able to increase it up to 99% – then, performance and accessibility of the service itself are not just critical, but rather fundamental parameters that influence the whole business. Theoretically, HostTracker should demonstrate accessibility close to 100%. However, an extensive growth of the service made this task hard to solve.

HostTracker was facing constantly increasing network traffic – a problem for seamless operation of the service. Inability to add new control servers on-the-fly, difficulties when maintaining not uniform and multiple-aged hardware was another limiting factor. Moreover, the desire to develop the service through wider protocol and network service support was meeting certain obstacles. “Unfortunately, for Linux there was a limited choice of ready-to-use solutions and libraries, while inventing something completely new was difficult”, says Artem Prisyazhnyuk, HostTracker director. “We had an idea of reviewing the stack of technologies we used for a more sophisticated one and after taking a closer look at the .NET platform, its potential in terms of scalability and network support, I realized that was exactly the thing we had been looking for.”

It was sure that migrating to a completely different platform should be a complex task – the project extended over three years. However, it was like blessing in disguise: during this period, the world has seen the cloud computing that seemed an ideal tool for solving both the scalability problem and putting aside one’s own whole infrastructure. Besides, the PaaS model allowed to remove most of the effort in terms of administering the solution and to control the application as a self-contained entity, to the extent of complete automation, and thus, Windows Azure had in fact no alternatives.

As a result, the second version of HostTracker, commercial operation of which started in May 2012, is already functioning under Windows Azure. Its central ingredient is realized as Web Role and associated with SQL Azure Database – it provides external portal, analytics and report generation, control of monitoring applications. The latter are ensured with instances of Worker Role, which also use SQL Azure Database to store their data and to provide the service scalability depending on the network loading. Agents are functioning as they did before, with the viability of their transfer to Windows Azure being considered.
Now, Host Tracker uses HTTP/HTTPS and ICMP protocols to monitor specific ports, including various methods (HEAD/POST/GET), and etc.
 

HostTracker instant check



Alarm reporting is available via email, SMS and instant messages. The customer can receive reports with statistics about resources being controlled and their performances. You can spend only 6 minutes to make monitoring settings for five sites, while the average response time in case of failure is limited by a couple of minutes, and it takes 1-3 minutes more to inform the customer about the problem. Using this service, anyone can check any site, including access from various regions.

 As a result, if on the one side the transfer to the .NET platform itself gave us the potential to modernize HostTracker, to optimize the application architecture and realize new internal functions, then, on the other side, the migration to the cloud allowed to refuse from less important, though time consuming activities such as administering the solution, and, first of all, to reach necessary performance indicators. Microsoft, for all basic Windows Azure services, declares 99,9% accessibility and guarantees monthly refunds, should this indicator be lower. This creates a firm ground for operating such services like HostTracker, as the accessibility is the most critical parameter for these applications. Using the cloud infrastructure also provides a better protection for the service: unauthorized access to the application and many types of attacks are effectively excluded, while the data safety is ensured by triple reservation.

HostTracker received another advantage from abandoning its own infrastructure. The service’s performance characteristics are also rather critical, for they directly affect the failure reporting system operation. In this respect, Windows Azure is virtually a drainless source of computing power. This means that by timely starting additional monitoring instances you can support Host Tracker functioning parameters on the necessary level. Moreover, the cloud environment is exactly what you need in order to make this process almost fully automatic, excluding further need for direct control.

more
HostTracker — Sites Monitoring Service

Every site owner knows how important it is to have your resource always operative and available for visitors. Periodical site unavailability has a bad influence even at its positions in the search engines (as Google representatives have repeatedly claimed), not to mention the fact that visitors are extremely displeased by such “accidents”...

How to be always aware of how properly your site is operated in real time?

HostTracker is an online website monitoring service, having rich functionality and good feedback of the customers, who are, by the way, more than 25 thousand (including the resources of such companies as Colgate, KasperskyLab, Panasonic etc.).

The job design of this service is the following: at certain specified intervals your websites and servers will be checked for availability and serviceability (the verification is performed from around the world), and in case of any problems you will receive notifications about the problems. In addition, uptime statistics for each site is collected, but it will be discussed later.

A quick site serviceability check may be performed directly from the service main page through typing its address in the upper right window and selecting one of the verification methods:

  • Http – website pages loading check
  • Ping – the server availability check (pinging)
  • Trace – the server availability check (tracing)
  • Port – random server port check

According to the check results a detailed report will be created on a separate page.

To become the HostTracker service client and verify the uptime and serviceability of your resources on a regular basis you need to register in the system and assign the appropriate tasks. Over time detailed statistical reports and visual graphics will be created for each task, greatly facilitating data analysis, outputing them in an understandable representative form.

Site failures and problems may be reported to (at your option):

  • Email as a letter
  • telephone as an SMS or a call
  • Skype or GTalk as a message

At that it is possible to set the notifications delay, their uploading time etc. – the settings are very flexible. By the way now I really miss such functionality at Monitorus, as it sends an SMS immediately when a problem occurs, regardless of the time of day, and as you can imagine, late night may be very fun because of this).

Another useful feature of the HostTracker service is the site content monitoring. You may set a list of the page keywords, at the disappearance of which you will receive the notification. Or vice versa – set a list of words, at the appearance of which you will receive the notification. The first case, for example, is good for paid links on other sites monitoring, and the second – to prevent virus activity in the form of additional code embedding on your website. Say, it is very helpful and very convenient!

Now a few words about the HostTracker site monitoring service rates prices. There are several service plans, differing in the maximum tasks number, check frequency, etc. However, there is also a full-featured trial period of 30 days, as well as the Free tariff, within which you may monitor up to two resources with an interval of 30 minutes. That’s not much of course, but as an option to try out all the features for free, and then decide on the appropriateness of the paid tariff transition, it is just the job. Good luck!

more
Twelve Ways to Improve Uptime Website

It is rather strange, but instead of going down web services usually grow so overloaded with the user requests that after slowing down they become unresponsive. But nowadays it is extremely important to provide secure and high-quality web hosting services, available anytime, as e-businesses is acquiring popularity. The owners of the websites demand perfect service, 100% uptime and quality assurance...

It is rather strange, but instead of going down web services usually grow so overloaded with the user requests that after slowing down they become unresponsive. But nowadays it is extremely important to provide secure and high-quality web hosting services, available anytime, as e-businesses is acquiring popularity. The owners of the websites demand perfect service, 100% uptime and quality assurance. Numerous techniques may be used to make access to the website smooth, thus increasing uptime. Site uptime informer

Here we offer you twelve methods recommended to achieve performance gain and uptime increase. Software optimization is required for that, as well as hardware optimization. A lot of software features may be upgraded with the use of general and improved coding standards, operated by the website manager. At the same time the company providing the webhosting services needs to improve the hardware constantly.
You can measure the accessibility of the website using monitoring services Host-Tracker.

Software Optimization
The following are the first six ways to improve uptime:

  • Split the databases
  • Separate the read an write databases
  • Use popular content caching more often and improve its quality
  • Optimize static content
  • Ensure compressed delivery of content
  • Optimize the content management system


To begin with, splitting  the databases – horizontally or vertically, or combining these two directions - is essential, making the connection more reliable. It is also good to differentiate the read and write databases, this giving an opportunity for master/slave setup. These actions are useful to extend the database infrastructure for future use.

Second, when you set the system to use better popular content cache, and to use it more often, your site will scale up more easily with many users operating it. Internet caching has no difference from computer caching: it supposes storing popular content at a separate container, allowing much quicker access to the information for the users.

To optimize static content is one more way to make the access to internet pages and files quicker. One of the means for it is to compress the images to the maximum extent possible (but, of course, preserving their high quality). Moreover, it is necessary to check if the web server may be used to deliver compressed content; this characteristic is not connected with the images, as they are already compressed files. Take care to have all the appropriate settings from the beginning.
.
One more appropriate thing to do is to improve the system of content management reducing the database calls number for each page request. It is like any type of connection: at the decrease of the information sending times the connection is maintained. In this circumstances, the number of calls to the database should be as low as possible – it will ensure that the users are able to access the content with the greatest speed.

Software and Hardware Optimization
The next six methods for augmenting uptime are:
Six more ways to augment the uptime are the following:

  • Use content delivery networks
  • Use emerging standards, such as HTML5
  • Improve the programming techniques
  • Add the content “expires” headers
  • Lessen the number of HTTP requests
  • Use Ethernet connections, allowing for more speed


Contend delivery networks allow for operation over larger amounts of media, at the same time improving the performance of the site. They are developed to direct the traffic to private networks. Such services allow operation over large media files, rooting the traffic along the Internet age, not straightly, averting extreme overloading. As the content delivery networks operate with large files, this unloads the servers, providing quick and qualitative connection.

Emerging standards, such as HTML5, include systems, improving the websites. It is achieved through advanced programming techniques, aimed at website and internet communications. Such standards do not 100 % assure that the website that uses them will not go down, but the in-built mechanisms of the code will act as the auxiliary mechanisms if it happens. Moreover, you should use improved programming methods while working with large loads and traffic spike.

“Expiers” content headers make all the automatically downloaded files cacheable for the visitors. So adding these headers to the content you will prevent the constant downloading of the browser. It blocks page review pointless HTTP requests. As well as the reduction of the database calls number, the reduction of the HTTP requests number will make the connection speed stable and not overloaded.
The last method is to develop Ethernet connection speeds. This will allow to cope with larger files and unexpected traffic spikes. A lot of hosting providers consider it as an excellent investment.

Speeds improvement and downtime reduction make the customers happier. Many of these methods to improve the web server or web site uptime may be achieved in a few minor steps. Such tactics, including Database rearrangement software optimization, caching improvements, content compressing, use of content delivery networks and content management systems, programming practices improvements and hardware upgrading will improve the web host as well as web site uptime, thus also improving your business.

 

 

 

 

 

 

more
Why do we need monitoring? The overview of the HostTracker service. Part 1

Why there is a need in monitoring? How the monitoring could help in the sites and servers development and testing? This review will answer to these questions and will also show how the simple desire to optimize your work may be transformed into a useful product for others, as well as, how not to lose the ‘startup spirit’ and always keep up with your clients.

HostTracker Company is one of the market leaders in the supplying of monitoring services for sites and various web services. It teems with a wealth of different constantly improved tools, which are taking into accounts the most recent tendencies and trends. How did this company emerge? Why there is a need in monitoring? How the monitoring could help in the sites and servers development and testing? This review will answer to these questions and will also show how the simple desire to optimize your work may be transformed into a useful product for others, as well as, how not to lose the ‘startup spirit’ and always keep up with your clients.

Introduction or the history of startup

Everyone involved in the IT sector must know the feeling, when a server (website, database, software, network) seems to be perfectly configured, but it suddenly stops to work properly. Solving this problem could take a lot of time. Meanwhile, this mess would go on, take place regularly or wouldn’t happen at all – but, nevertheless, that’s the worst, as it wouldn’t be clear when it shows up another time. Moreover, what if this happens during handover the project to the client? Pondering over all these things caused HostTracker to appear.

A founder had always tried to make his work on objects as brilliant as he could at his main job, so he decided to automatize the process of monitoring. If at that time (at the beginning of 2000), there were reliably working monitoring services – possibly, HostTracker would never have appeared. Therefore, he had to write a simple script to check his bulk of sites. However, the script faced the same problems that were mentioned at the beginning of this paragraph. From time to time, the script didn’t work at all or didn’t work properly.

So, that’s why, we had to optimize the script a little and make it more reliable, as well as, through the duplication and distribution it on several machines. After a series of optimizations the idea crossed our minds that it could be useful for someone else, and HostTracker became public. With the advent of a variety of clients – we decided to monetize the efforts. As you can see, our service appeared to solve personal problems, but during the process of development has become available to others to help them solve the same problems, which, at one time, we faced.

Monitoring: the main points

This part of the review contains information about the most popular feature - regular check of the site or other entity available from the network for immediate identification of emerging problems. These checks can be run on different protocols: http (s), icmp (aka Ping), port (check any port over TCP) etc. It is worth noting, that there are different approaches to monitoring. There is an internal monitoring - when the state of the site is estimated by the software hosted on the same server. To put it tentatively, there may be included such tools like Google Analytics– built in the page script sends information about customers who entered the site, and can make indirect conclusions about the site performance. The other type of monitoring - external, or, as lawyers say, "monitoring by a third party." It is embodied in simulating the logging in of real users with real addresses to the site, and making conclusions on the real server replies to the sent requests. Further we will talk about this method in the review.

Infrastructure or how it works

For easier understanding, the infrastructure can be divided into two components: the "internal" and "external". The “internal” is placed in the cloud and consists of computing servers, databases, file servers etc. All of these components belong to HostTracker and are operated directly by HostTracker employees. The “external” component - nodes or agents, which are placed around the world and serve as independent servers inspectors, similarly to "Secret shoppers" at the stores. They are testing the sites and other entities by creating the standard requests for checking protocol. If it is a web site test, then it will be the usual http requests and there will be no difference between these requests and requests of real visitors.

These servers are completely independent from each other and from internal system structure. Everything what they do – receive a list of sites for checking from the central server and give it back the check results. Some of these servers are being rented by the HostTracker, whilst the majority of them belongs to the partners. These partners are providing them for free or with a significant discount, in return for backlinks or discounts for our services, or just due to friendship relationship.

This kind of infrastructure allocation is a result of monitoring service performance algorithm.

The service performance algorithm

Regular checks are being done due to the client’s predefined interval, beginning from one minute. When it comes to testing, the server sends the task to one randomly selected agent – a part of the external HostTracker network. It is performing checks by a given protocol, and sending back the response of the checking server. These results are being processed on the “external” side. If it happens to have a positive response - nothing happens, there will be only a record in the database about this (it is available to the client in a form of an inspections log). If an error has been noticed, then tasks are immediately created to verify, again, this site by other randomly selected servers from the general network. After that, the answers from all these servers will be analyzed.

If the error hasn’t been confirmed by the majority of servers - it remains in the log and there is no reason to worry. Apparently, anything can happen: the network lag, requests overload and everything. If most or all of the agents do confirm an error - then it is assumed, that the trouble occurred and there is a serious problem – likely, at that time, a lot of people can’t get to the site. Moreover, almost all commercial sites will suffer from a great loss of money in this situation.

Error handling and clients notification

According to the settings, after identifying the problems, a lot of different things can also happen. The problem initial diagnostics is being done at once. If there is any error, the code of this error is recorded, otherwise there will be a record of the protocol response. This data can be used for detecting the reasons of the error, for example, network failure, server failure etc. However, first and foremost, the client is interested in getting to know about the problem. So, if you want to be aware of any errors at any time, you should register your phone number, e-mail or other communication channel to receive notifications from HostTracker.

These notifications may be sent to different people, with different contacts and at any time. Truly, a lot of interesting features are there to offer. The message can be sent immediately, which is done the most frequently. Although, that’s not enough for the particular customer to be satisfied. Firstly, the "unimportant" sites do exist and it would be inappropriate to wake administrator up because of the short-term downtime. Secondly, there are "important" people, that shouldn’t be bothered because of different insignificant problems. Therefore, HostTracker offers a feature of the alerts escalation. As well as, HostTracker would send a notification to a specific address after some time of the site’s fall, if it didn’t recover by itself.

Moreover, you can create "work schedule" for each contract - set the time interval during which, it is possible to send alerts. So, HostTracker wouldn’t disturb this person at other time. It happens to be very useful for some customers. For instance, this configuration will send an alert to the particular person between 8:00 am. and 7:00 pm., in case the site has been “off” for one or more hours:

We will describe a wide variety of other service functions in the next reviews. Also, you will find all histories of their emergence and development, the examples of their usage and other things from our own experience. It is worth noting, that one of the main advantages of the service is the orientation to clients. Many service functions have been invented due to clients, friends and partners requests, enabling them to solve their specific technical problems, the solution of which on their own would require a lot more resources. Therefore, we’re looking forward to your feedbacks and suggestions!

more
What could we check by using the cloud services? Part 2

  In the beginning, HostTracker company was founded on the basis of a simple website to provide free customer services. Though, a few years later, this startup developed a wide variety of tools serving to solve various problems, including different network issues. In a series of publications, we have decided to describe thoroughly all the features of our service, also to share our experience in the development of such projects with you and to mention interesting challenges that we faced. 

In the beginning, HostTracker company was founded on the basis of a simple website to provide free customer services. Though, a few years later, this startup developed a wide variety of tools serving to solve various problems, including different network issues. In a series of publications, we have decided to describe thoroughly all the features of our service, also to share our experience in the development of such projects with you and to mention interesting challenges that we faced. Moreover, for those seeking an example of how to sell something that had been made for themselves, our experience would be useful, as most of our features were developed due to our personal needs.

                In the previous part of the review we have talked about the history of the service and the most basic functions - regular inspection of sites and servers, and what is more, notification of their efficiency. Before starting to describe more advanced features, we should write where do all these ideas come from and how to prioritize them. One of the key secrets often used by entrepreneurs is to follow the statement: all people are unique. All customers’ requests are unique, so you have to learn how to deal with them. Therefore the IT sector is utterly susceptible to this factor, as a great number of customers have profound knowledge and diverse experience. Nevertheless, part of the problems can be solved with available resources. However, the main feature of our work is that, frequently, we have to evolve something. Most of the HostTracker’s functions were developed or adapted due to the conveniences and needs of the particular people. We are also a part of that people, as having rather large infrastructure, and also need to have everything work properly. Therefore, we ourselves are the most picky client.


Precious little things

It worth noting, that in addition to different regular checks, there are other useful tools. They include monitoring of the domain and SSL certificate expiration time. This seems to be negligible, but could bring a lot of unexpected inconveniences to work. These functions appeared in HostTracker, when one of our personal domains had expired. Moreover, large companies also frequently face these problems, as the prolongation of the domain /certificate expiration time depends on the unreliable human factor. Therefore, a notification that the domain should be prolongated, is stored not only within spam folder (already overflowed with continuous marketing messages from your hosting company), but also to the folder with the data of website downs. As well as, the SMS notification capability still exists. That’s why these features are being so handy.

Another interesting feature is the domain check to see if they are blacklisted in DNS-based lists. These lists are independent and are generated separately using different algorithms. What is more, they were mainly created for filtering of the suspicious entities. Each administrator can configure own web server in different ways, for example, not to receive messages from the servers from a specific list. It helps fight off spam, malware spread, DDoS attacks and other problems. But all of these lists have their own algorithms, and there is no guarantee that in the result of any coincidences your website wouldn’t appear in any of these blacklists. Moreover, according to the statistics, this is happening on a regular basis with the most innocent sites. For example, no one can guarantee that a hacker wouldn’t use your nearby IP for different spam attacks. In this situation, the entire range of IPs would be considered as unreliable. What are the consequences of that?  Your messages wouldn’t be delivered to customers, the site wouldn’t be so easily found in search system and so on. Furthermore, you will find out this problem when the changes become critical or even irrevocable. Therefore, the monitoring and notification of DNSBL are also essential.

The content check

Here is a good example of how the usage of functions may exceed developers expectations. We have mentioned about several such cases earlier. Actually, nowadays a lot of things have a web interface whilst for others – it could be easily created, if needed. Therefore, it was developed not only the check function of whether the page was loaded completely using simple parsing, but also another mind-boggling things of this check. Adapting to different customer requests, this feature has become very flexible. It may look for one or plenty of words from the list at once. Moreover, it may detect the emergence of certain phrases. This feature may also raise as an error the whole line that contains the keyword. For instance, if there is a kind of server-status page (“Server 1 OK” etc.) and it shows “Error”, then the message will be “1 Server Error”.  In this case, all diagnostic is already done, and you can start troubleshooting immediately.

What if it happens, that the server should be down?

In addition to the notification of the failures of the sites, HostTracker provides another important function – gathers statistics of each examined site. When the various buttons on the sites were popular – HostTracker’s button also often appeared with the figures of website attendance, the weather forecasts and other things like that. Now it is possible to use a widget, but still the button is also available for retro fans. In addition, statistics is very important for managers. They constantly want to know whether the website and administration of it are working properly. Therefore, there is another useful function - the maintenance planning. Even the most stable sites and servers must be updated or rebooted from time to time. At the same time, it’s not the desired to lose so-called “9s” in terms of uptime. Planning of the maintenance let us achieve two goals (together or separately). This includes: not to send error notifications and not to record errors to the statistics during a specific span of time. Of course, it seems to be a kind of cheating, but outlined maintenances are justified, especially in excluded time. In addition to this, different verifications have being done and written to the log during maintenances. It can be useful for webmasters and administrators, as log let determine exactly the duration of updating or restarting processes, any occurred errors, other breakages etc. Moreover, thanks to that, the whole process of error emergence could be tracked: from the stage when the server wouldn’t be available for some time to the stage when the application would return an error.

Maintenance can be scheduled as a one-time job or on a regular basis. For example, if the backup is done every night, or a new release - every Thursday. The only condition is that the maintenance schedule should be made up at least 12 hours prior to the site/server nearest suspension period of time. This is done to ensure that all maintenances won’t be responsible for any pity unexpectancies, and statistics provided by HostTracker will be trustful.

A kind of an epilogue

We are frequently asked why are we doing that. The same things can be done without HostTracker’s help.  And you know what - definetely, they can. Especially, if you need only one tool. Many people are talking, that the whole Business World is built on human laziness. By solving routine problems, HostTracker provides a slice of work-free and responsibility-free time in the customer’s schedule. Truly, not everyone is able to assemble a car by himself. We look up to the people, who are eager to create something good for personal needs in our field, but most people don’t want to spend their free time for doing something like that.

Additionally, our clients are: non-IT specialists; IT specialists who have to report something to their managers; managers themselves; fans of reliability – they use their own tools and take advantages of someone else’s; and many other groups of people.

All in all, we are always looking forward to your comments.

more
Shellshock vulnerability online check

Considering the recently discovered Shellshock vulnerability, HostTracker has created a tool for testing it.

Check your server for vulnerability

How does it work?

It is developed for a Linux server with a web server installed on it. The algorithm is very simple. We consequently generate 4 http requests:

  • 1. Ordinary request
  • 2. The request tries, using vulneratility, post a "harmful" cookie which causes 2-seconds delay in respond to our special http request.
  • 3. The request tries, using vulneratility, post a "harmful" cookie which causes 4-seconds delay in respond to our special http request.
  • 4. Same as #3

How to understand the result?

We compare response time for all 4 requests. Three situation are possible:

  • 1. Vulnerability found. We may affirm that if the difference in responses is about 2 seconds for requests without cookie and with 2-second-delay cookie, as well as for requests with 2 and 4-second delay cookie. It means that our request was able to use the vulnerability and set these cookies.
  • 2. Vulnerability not found. All the requests have about the same response time. The cookies, likely, were not installed because there is no vulnerability.
  • 3. Uncertain situation. If the response time differs widely, without coincidence with preset by cookies delay, we can not say for sure. It could be if the server is under high load. To check this, we use two requests with same cookies (#3 and #4). If the response time for two same checks varies, we make a conclusion that the response time is not affected by cookies. At least, not only by them. So in this case our method can not detect vulnerability

Safety of checks

Our test can not damage your server. The risk consists of appearance of one extra-cookie, which is used only for our requests and can not affect normal work-flow of your site.

more
Snapshot - instrument for site supervision

How does the site look like when I’m not looking at it? What if it looks bad or does not work at all? HostTracker offers an instrument for site supervision - snapshot feature. Let’s take a look at its practical application.

How does the site look like when I’m not looking at it? What if it looks bad or does not work at all? HostTracker offers an instrument for site supervision - snapshot feature. Let’s take a look at its practical application.

What’s going on with my site?

Now it’s usual to use different services and applications for site maintenance and support, and sometimes they do report some problems. Often we feel the lack of information - Google Analytics or a similar service reports the downtime and renewal, but likely we will never know what exactly has happened. To investigate the issue, it is necessary to review the logs, write to hosting support and perform many others exhausting actions, frequently - with no result. There are also more interesting cases - when a site is not available from a certain country or is not downloaded completely. Such problems could long for months, or even years, till they are accidentally detected. One more important issue - content check. It will automatically review the content of the site and informed the responsible staff in case it has disappeared - for example, something has not been able to be downloaded from the database. But it’s hard to find the cause if the issue is short-term, because people usually do not sit in front of a laptop refreshing the page every minute. To resolve the problem, HostTracker offers a new feature - snapshot. It is very simple in use and does not require any additional adjustments. The service simply makes a snapshot of the checked page every time and saves it for review in two ways: page source code and html-view. This let you easily see how the page looks at the moment of failure, understand what’s wrong and fix the problem quickly without spending time for diagnostics. It saves lots of time for server administrator, developers and other concerned people.

How does it work

Doing the regular checks, our servers with predefined interval try to download the checked page. Additional algorithms could be used at the moment - the page could be parsed for keywords to make sure that this is the one we are looking for (there are cases when an error page returns 200, Ok, http code, or when redirection is activated in case of error). If there is no error - fine. But if there is, it will be written down into the HostTracker log, which is easily available from the web. Then, notification are sent and a snapshot is made.

The snapshots could also be found in the log - if several errors were detected, a different snapshot will be available from each one.


Though there are some remarks. First, we do not run javascript while making snapshot - same thing for regular check. Second, the error must be detectable. It means, the server must return something. In case of timeout or connection error - snapshot will not help, and only a corresponding record will remain in the log.

more
Tags: snapshot
Uptime and website monitoring

Website monitoring is a process of supervision over the performance of the site. HostTracker is a powerful tool which serves that purpose.

Website monitoring is a process of supervision over the performance of the site. Usually it is used to keep an eye on commercial sites or other pages for which high availability is very important.

Companies, which provide website monitoring services, let their clients to check a website, a server, port or other available from the Internet entity. The responses are collected and analyzed. Usually, the monitoring is performed from different locations, distributed over the whole world or the specific continent or country. Such monitoring is called distributed monitoringand helps to detect network-related issues as well as site or server-related. Also, distributed monitoring often makes possible to analyze the site performance from the places which are close to the real customers, instead of some distant locations which could have high latencies. The collected information could be found in a different form: email reports, graphs and different smart dependencies, to help the client to get a comprehensive view of the site's performance. Parameters like load time, speed and others can help to optimize the site performance. In case of critical error, monitoring services use variety of notification methods to deliver the alert to the client: SMS, voice call, instant messengers, email and others. This, together with immediate diagnostics, helps responsible persons like server administrators or developers to fix the site as soon as possible and minimize the duration of the failure.

Why is this important? For commercial sites, working time is proportional to their income. Roughly speaking, 2 hours of failure per day means that 1/12 part of the potential clients are lost. Even more - loyal customers also can find a more reliable competitor in case they can not receive their services/goods when they want. For other types of sites, like government, educational, NGO this is very important too. If people can't find the information fast, they'll find another source. Some parameters like site speed are important for search engines, others - database connectivity, for example - can greatly affect the convenience of usage of the site. Monitoring of some internal values like CPU load, memory consumption and disk space are important for administrators in order to prevent performance degradation. Another important purpose is verification of SLA (service-level agreement) of hosting provider. For technical issues, no site can be available 100% of time during long enough period. Sometimes servers are rebooted, updated or upgraded. So each hosting provider guarantee some specific value, which is called uptime, that shows how long can a site be down for technical reasons. Uptime is usually measured in percent. In this table it is shown for how long a site could be down for each uptime value:

  • 90%          876 hours
  • 95%          438 hours
  • 99%          87,5 hours
  • 99.9%       8 hours 45 minutes
  • 99.99%     52,5 minutes
  • 99.999%   5 minutes 15 seconds

If the real site performance does not correspond to SLA, it could be a reason for claim and refund request. Also, it can help the customers to select the best hosting for their needs.

Monitoring companies often provide some additional services, like vulnerability check, virus scanning, domain and certificate expiration check and many others, in order to make a useful product for their customers.

Different ways to monitor

The monitoring, based on the purpose, can be performed in several ways. Internal monitoring tools require some software to be installed into the monitored system, for example, corporate network. It helps to detect network issues, system performance and exclude or catch hardware and performance issues. External monitoring is performed from outside. It's purpose is check the availability and performance of the system by the third-party's eyes. Real user monitoring is external monitoring which simulates the real visitor of a site. Depending on complexity, such monitoring can analyze the page loading, content, sometimes - even design problems. Most advanced monitoring can offer its client to create a scenario for a visitor. This is called transaction monitoring and can perform some steps one-by-one: like load the page, navigate through menu, make a purchase. Passive monitoring is performed by a code which is integrated into the website code and sends specific information to the collector server each time the page is loaded. It helps to analyze customers actions on the site and analyze the traffic.

Monitoring services usually support different check protocols, and can monitor not only the websites, but also other entities like a file servers, mail servers, specific ports etc. Depending on task, monitoring interval can vary from several seconds to once per day.

more
Share:
Send to Twitter Send to Facebook Send to LinkedIn Share on Google+
Blogs:
HostTracker blog HostTracker page on Facebook