Yes. Here is how to do it. Network Server Monitor monitors UNIX system by calling RSH script. The success or failure of the RSH command is determined by matching its standard output to a given pattern.

Network Server Monitor UNIX Shell Script screen shot
RSH is a client process that opens connections to rsh daemons, sends a command to be executed on the remote server and retrieves its output, both stdout and stderr. The connection is made on standard port 514 (tcp port for the shell/cmd protocol). GFI Network Server Monitor can launch scripts on Linux/Unix machines and analyze the output.
GFI Network Server Monitor requires the following to launch a shell script on a remote UNIX/LINUX machine:
The remote UNIX/LINUX machine must have the RSH daemon running;
The remote UNIX/LINUX must have an entry in its .RHOSTS file for the computer where the GFI Network Server Monitor service is running on; this entry must include two values: the host name of the GFI Network Server Monitor server and the username to use.
A RSH Shell Script rule takes the following parameters:
Remote Host - IP address, DNS host name or WINS/NetBIOS address of the remote host on which to run the command;
RSH Username - The username to use on the remote host. If not specified, the service account name will be used. The value must be configured in the .RHOSTS file on the remote host;
RSH Command - Specifies the command to run on the remote host;
Script timeout - Specifies the maximum number of milliseconds to wait for completion of the script; if the script takes longer, it will be terminated. Default value: 3000 milliseconds;
Match following string - The string that should be present in stdout to consider the script execution as successful;
Consider as success/error if stdout matches string - If string matches, consider the result as error or as success.