Forum Discussion

ingard's avatar
ingard
Icon for Nimbostratus rankNimbostratus
Jan 25, 2016

irule to log slow and/or tcp profile timed out requests to backend

Hi   I'm trying to identify which requests are causing our backends to stop responding/hang/fail. I was thinking some sort of timer and/or catch the tcp timeout rst maybe? I've been trying to figu...
application delivery
iRules
LTM
Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Jan 25, 2016

Hi Ingard,

unfortunately there is no way to access TCP flags (PSH, RST, etc.) using iRules.

But you may try this snipped as a starting point to identify slow server responses...

 

when RULE_INIT {
    set static::timeout 10000   ; msec
}
when HTTP_REQUEST {
    set debug(request_url) "[HTTP::host][HTTP::uri]"
    set debug(id) [after $static::timeout {
            log local0.warn "$static::timeout msec timeout reached for \"$debug(request_url)\""
    }]
}
when HTTP_RESPONSE {
    after cancel $debug(id)
    unset -nocomplain debug
}
when CLIENT_CLOSED {
    if { [info exist debug(request_url)] } then {
        log local0.warn "Connection closed without HTTP response for \"$debug(request_url)\""
    }
}

 

Cheers, Kai