General Http check of your website. Each test simulates the download of the page by a real customer.
Check through ICMP (ping). If Ok, the site or the hardware is available online. If failed, either the checked server is unavailable, or ICMP is disabled for this point. You can use other types of check for further analysis. If part of checking servers return failure, the site could be banned in certain countries or some locations could be accidentally blacklisted in order to avoid some ddos attack in the past.
Advanced check through ICMP. Does the same thing as "traceroute" program in Linux and macOS, or the "tracert" program in Windows. Shows the path from the customer to the site, checking each hop on the way. Can help to evaluate which junctions are weak and find out if a delay is caused by the local or network-related problems.
Check of the specific port via TCP. This kind of check is useful to monitor network applications. If Ok, the port is open. Failure means or closed port, or complete unavailability of the server. You can use other types of check for further analysis.
Check if a site has some known vulnerabilities. Among them: ShellShock, vulnerability of sites, hosted on Linux servers, can cause ability of a third person to place unauthorized cookies; Logjam, vulnerability related to security of https connection; Poodle, check if the server uses modern SSL version as some older are easy to breakthrough.
Find the information about person or a company who owns the domain.
Check if a site is available from Russia. Some sites are banned by Russian government.
For daily monitoring you should
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