Create a node based on an event

Hi ottleydamian,

dont think iCall would be a good choice for your requirement.

ISTAT based triggers adding some (unpredictable) latency and LOG based triggers wont be able to pass the entire log-line (including the requested HOSTHEADER) to your iCall scripts.

It would be far more stable and elegant to SIDEBAND out of your iRule to F5's REST-API and create a new pool member or to use DevCentrals "Action On Log" contribution (https://devcentral.f5.com/codeshare?sid=430) to automate the pool member creation.

Beside of this, what is the purpose of having those pool members in place? You could also perform a a simple DNS lookup (after visiting DNS-Caches) within your iRule and then forward the traffic based on the DNS responses.

when HTTP_REQUEST {
     Extract the HOSTNAME value...
    set fqdn [URI::query [HTTP::uri] hostname]
     You may want to add some additional tests to make sure the passed HOSTNAME values are legit!!!!
    if { $fqdn ne "" } then {
        if { [set resolved_ip [table lookup "dns_cache_$fqdn"]] ne "" } then {
             Found a cached DNS response...    
            node $resolved_ip
        } else {    
             Need to DNS resolve the IP address
            if { [set resolved_ip [lindex [RESOLV::lookup @8.8.8.8%1 -a $fqdn] 0]] ne "" } then {
                 Found an IP address. Updating DNS cache (for 60 sec) and forwarding the request to the just resolved IP.
                table set "dns_cache_$fqdn" $resolved_ip indef 60
                node $resolved_ip
            } else {
                 HOST not found...
                HTTP::respond 200 content "HOST not found..." "Content-type" "text/html"
            }
        }
    } else {
         Empty hostname param...
        HTTP::respond 200 content "Empty hostname value..." "Content-type" "text/html"  
    }
}

Cheers, Kai