Generate qkview or ucs on failover

Problem this snippet solves:

This iCall script collects a qkview and a UCS after a failover event. It is hardcoded for traffic-group-1.

How to use this snippet:

Implementation Details

This iCall script requires v11.4 or higher. The script can be loaded via:

load sys config merge file /var/tmp/handle-failover.conf

Code :

sys icall script detect-failover {
    app-service none
    definition {
        # prime the iApp to assume it's standby so that it doesn't generate
        # a qkview+ucs on the initial run (which wouldn't be a state
        # transition)
        set old_status standby
        while { 1 } {
            # this will block until another event is present. As we only
            # subscribe to HA events, that means that whenever an event is
            # raised it represents a new message from SOD
            EVENT::get_next
            set new_status $EVENT::context(/Common/traffic-group-1)

            # detect if we just went standby
            if { $new_status eq "standby" && $old_status ne "standby" } {
                puts "failover detected - i am standby now!"

                set date [clock format [clock seconds] -format "%Y%m%d%H%M%S"]
                set settings [tmsh::get_config sys global-settings]
                set host [tmsh::get_field_value [lindex $settings 0] hostname]
                puts "generating qkview /var/tmp/$host-$date.qkview"
                exec /usr/bin/qkview -f /var/tmp/$host-$date.qkview 2> /dev/null &
                puts "generating UCS /var/local/ucs/$host-$date.ucs"
                tmsh::save sys ucs /var/local/ucs/$host-$date.ucs
            }

            # save the state
            set old_status $new_status
        }
    }
    description none
    events none
}
sys icall handler perpetual handle-failover {
    script detect-failover
    subscriptions {
        failover {
            event-name FAILOVER_STATE
        }
    }
}