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David_G__33241's avatar
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Dec 16, 2015

Execute iCall from iRule

I have an iRule that executes a sideband connection in order to execute a bash script that runs a bunch of openssl commands. I would like to implement this using iCall so that I can eliminate the sideband connection and make the script part of the big-ip configuration.

The script and handler are pretty straight forward (thanks to the DevCentral community):


sys icall script helloworld_script {
    app-service none
    definition {
        set ifilename [exec bash -c "ls /config/filestore/files_d/Common_d/ifile_d/**"]
        exec /bin/bash $ifilename
    description none
    events none

sys icall handler triggered helloworld_trigger {
    script helloworld_script
    subscriptions {
        helloworld_subscription {
            event-name helloworld_event


I can test this with:


generate sys icall event helloworld_event context none


The part I am not sure about is executing this from an iRule. The only thing I have come across is to Jason’s article which talks about using an ISTATS::set trigger from the iRule. Is this really the only way to execute an iCall from an iRule?




1 Reply

  • There are three ways to trigger this and it is configured based on the handler - triggered, perpetual and periodic. If you want it triggered then you need to create the event and the event only has iStats configuration, which you would call from the iRule using ISTATS::set or ISTATS::incr.