3.5.1 Matrix Server Administration Guide

Chapter 14: Configure Device Monitors 246

Start scripts must be robust enough to run when the device is already

started, without considering this to be an error. Similarly, Stop scripts

must be robust enough to run when the device is already stopped,

without considering this to be an error. In both of these cases, the script

should exit with a zero exit status.

This behavior is necessary because Matrix Server runs the Start and Stop

scripts to establish the desired start/stop activity, even though the device

may actually have been started by something other than Matrix Server

before the ClusterPulse daemon was started.

The Start and Stop scripts must also handle recovery from events that

may cause them to run unsuccessfully. For example, if the system runs

out of swap space while running a Start script, the script will fail and exit

non-zero. The device could then become active on another server, causing

the Stop script to run on the original server even though the Start script

did not complete successfully.

To configure scripts from the command line, use these options:

--recoveryScript <script> [--recoveryTimeout <seconds>]

--startScript <script> [--startTimeout <seconds>

--stopScript <script> [--stopTimeout <seconds>]

Use Custom Scripts to Modify Start/Stop Activities

Some built-in monitors perform starting or stopping activities. If you

need to take an action before or after the starting or stopping activity, you

can create a Start or Stop script for the action and specify it on the Scripts

tab for the monitor.

The default order for starting is:

• Run the monitor’s starting mechanism (if any)

• Run the custom Start script (if any)

If you want to reverse this order, preface the Start script with the prefix

[pre] on the Scripts tab.

The default order for stopping is:

• Run the custom Stop script (if any)

• Run the monitor’s stopping mechanism (if any)