Redirect traffic to other pool member if other sends http error code 502, 503 and 504

These error may be transient so marking a server down may not be ideal. The following iRule was suggested for a similar request here https://devcentral.f5.com/questions/irule-to-catch-4xx-and-5xx-http-error-codes:

when CLIENT_ACCEPTED {
set retry 0
}
when HTTP_REQUEST {
    set http_request [HTTP::request]
}
when HTTP_RESPONSE {
    if { ([HTTP::status] starts_with "4") || ([HTTP::status] starts_with "5")} {
        incr retry
        if { $retry <= [active_members [LB::server pool]] } {
            HTTP::retry $http_request
        } else {
            set retry 0
        }   
} else {
    set retry 0
}

}
when LB_SELECTED {
    log local0.info "Run $retry";
    if { ($retry > 0) && ($retry <= [active_members [LB::server pool]])} {
        LB::reselect pool [LB::server pool]
    }
}