SLCheck starts different batch files in dependence of the result. The batch files can be modified by the user. The results are logged in a csv file (comma separated values). The log files can be used to create Service Level Reports.  

SLCheck can monitor your company’s internet connection by requesting the proxy server on port 80 (HTTP). Two different URLs can be requested simultaneously. If both requests produce a timeout, a batch file is executed which can send a warning notification. While SLCheck is a command line utility, it is possible to request the services periodically (e.g. once a minute) in order to monitor them. This can be done by creating a Scheduled Task in Windows.  

SLCheck can help you if ...

• you would like to monitor some critical HTTP, FTP, SMTP, POP3, Citrix servers (and others) in your company network or on the Internet and would like to be informed if one of the servers is offline

• you would like to monitor your company's Internet connection by requesting two different URLs periodically

• you need availability statistics to show your provider/boss - or to improve your service quality

• you have already installed system management software and would like to monitor some DMZ servers without opening more than one firewall port - or just want to save some money for the expensive system agents

• you have to do some programming tasks and need to ensure that a service is available before running a job

Let's have a look at this example:

SLCheck -p 80 -a www.myserver.com -u / -r "HTTP/1.1 200 OK"

SLCheck tries to establish a connection on port 80 (HTTP) with server www.myserver.com and sends a GET request. The return string "HTTP/1.1 200 OK " is expected. There are 3 possibilities for the attempt:

• The connection can be established and the server answers with the expected text. Batch file CheckOK.cmd will be executed.
• The connection can be established but the server answers with a different text. Batch file CheckMismatch.cmd will be executed.
• The attempt to establish a connection fails within the timeout value (default: 2000ms). In this case batch file CheckTimeout.cmd will be executed.

There are two additional batch files for service level management.

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