portcheck

Name

portcheck -- Checks to see if ports are up or down.

Description

Portcheck is used to determine if ports on the network (which may be local or remote) are open and accessible. On non-Windows platforms, portcheck does this by sending SYN packets but not acknowledging the reply, which is basically half of a full TCP connection. This is quicker than opening full connections, and usually places less load on the system. These types of connections aren't possible in Windows, so full TCP connections must be done. This module can be given IP addresses or hostnames, which are resolved by portcheck using DNS.

Configuration

Configuring portcheck is quite simple. Each desired port is set with the "checkPort" variable. If only a port number is given, then localhost is assumed. Remote ports are specified by giving the host and the port, separated by a colon (':'). Any number of ports may be given. For example:

config
{
	checkHost = 22
	checkHost = mycompany.com:80
	checkHost = db1:3306
}
		

Windows users may configure portcheck though the RSPD Configuration window. Port are added and removed from a list. See Chapter 2 for more details.

Thresholds

Portcheck also supports thresholds. Any of the ports which were given to check may be used in a threshold. The only two allowed operators are "==" and "!=", which can be used to compare against the words "up" or "down". Therefore "!= down" and "== up" could be used interchangeably, as coule "== down" and "!= up".

Here are some example thresholds:

# Example thresholds for portcheck
thresh1.threshold = PortCheck.22 == down
thresh2.threshold = PortCheck.db1:3306 == up
		

History Data

The portcheck module will save boolean values for each port it is given. This data, using the RSP History Viewer or RSP Web tools, can be used to show service availability over time.