Database Monitoring
Database monitoring Database monitoring - DB check for access and regular execution of the specified query.

Database monitoring feature allows to run a query during every check and react in the appropriate way on the result. Also, it is possible to check just possibility to connect to DB - by ignoring the query field. To set the monitoring, fill the connection data: DB server address, port, database name, login and password of a user for connection. We strongly recommend to create the new user with limited rights. However, do not forget to provide him enough rights for performing the supposed actions. Also, it is necessary to add HostTracker servers addresses, to the whitelists on firewall or other blocking software, to allow the access. The addresses are permanent, and are listed on the same form.

Create ContentCheck Task

There could be arbitrary query - SELECT, UPDATE, DELETE, INSERT, execution of stored procedures (like scheduler), results comparison, logical operations. The only restriction is execution time - it should not take longer than 30 seconds. Otherwise, the timeout error will be reported.

It is recommended to create the queries which display the necessary value in the first row of the first column. This result can be analysed. For UPDATE, INSERT, DELETE queries the number of affected rows is analysed. There are different ways to analyse the resulted value by comparison with specific preset - equal/not equal/higher/lower/in range. In case the condition is not satisfied, no connection to DB, query timeout - the error is reported.

Create ContentCheck Task
  • CM.Glossary.WebsiteMonitoring
  • CM.Glossary.ContentCheck
more glossary
"Independent verification of website availability is valuable. Let's us support our customers better."
- M.
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


Results of the test

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 blog
Thank you for feedback!
 
Sign In
Sign Up
Prices & packages
Our monitoring network
Home > Glossary > DNS
DNS DNS - domain name system, a system for locating a web site.

DNS - domain name system. This system helps to find a real server by virtual site name. The system is realized by the hierarchy of DNS servers, each of them holds information about specific domains and may delegate such role to lower stage servers. Let's take, for example, site www.host-tracker.com. The upper domain is .com, so the request is made to the server, which is responsible for all .com sites. It knows where each site is located, or at least, where is another server, which knows for sure. If you get "Server not found" message, that means no record exists on the DNS server for the site name you've requested.

Each time you enter an address into the browser - a DNS request is made, in order to find where the site is located. To make this process faster, DNS data can be saved into a cache. If you own a site and decide to change its name for some reason, or if you have just created the new one - you should keep in mind that DNS cache needs some time to be updated globally. Usually, it happens within couple of hours, but it can take up to 48 hours. That's why sometimes a newly-hosted site can not be visible for some time.

  • CM.Glossary.WebsiteMonitoring
  • CM.Glossary.Uptime
  • CM.Glossary.WebHosting
Share:
Send to Twitter Send to Facebook Send to LinkedIn Share on Google+
Blogs:
HostTracker blog HostTracker page on Facebook