Node Status change to trigger Script

I don't think you want to do this with iRules. First, they are transactional and event-based, so using them as a warning trigger is difficult at best. Second, unless you want to do it via event logging or HTTP::retry, there is no real way to jump outside the iRule sandbox to execute something.

 

 

There are three ways you can get this done: iControl, on-box shell scripting, or TMSH scripting. With iControl, you would need to run a script from an external box, monitoring your selected pool on a regular basis, and taking action on any changes. The same is true of the other two methods, only they would both execute on-box.

 

 

The one I would use is probably TMSH. Here is an example of a monitor script:

 

 

http://devcentral.f5.com/wiki/default.aspx/tmsh/WatchPools.html

 

 

Hope this gets you started!