Invoke java method from iRule or iControl

From a server-perspective, there is no direct way to call out to outside methods from our iRules or iControl. For iControl, you could make a call to an outside object from your client, but not in the server implementation. Now, that's not saying it can't be done, just not directly. We've seen folks use iRules issuing log statements to the syslog system and then configured the syslog system to execute a script based on entries in the log. You can also use the high speed logging (or external logging with the log command) to pipe syslog based messages to the target of your choice. You could implement a syslog server that listened for your commands and then did something on that behalf. Both solutions do fairly the same thing. The first is on the LTM, the second would be on a target system of your choice.

 

 

-Joe

 

Joe, thanks for the post. I think I have a rough idea now. On the same token, can I add/delete LTM pool member from inside iRule based on the return value?

 

Thanks Roman

Unfortunately that's a no as well. iRules are purely a data-plane engine. adding/deleting pool members is a control-plane function and that is handled from external processes like the GUI or iControl apps. Now, you can make a data-plane decision by sending traffic to/from certain pools or members within a pool, but you can't add/remove directly.

 

 

But, you could do something like I mentioned before where you log a message to the syslog system and have a monitoring process look for certain messages and then perform the actions based on those messages with a shell command.

 

 

-Joe

 

ok, got it, thanks.

 

Roman

 

 

P.S. http://devcentral.f5.com/wiki/default.aspx/iRules/LB__down.html states it's possible to take the pool member down from inside an iRule. I haven't actually tried it. Any thoughts?