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JiriPetruzelka_'s avatar
JiriPetruzelka_
Icon for Nimbostratus rankNimbostratus
Dec 04, 2015

GTM with LTM Request Response Stats

Hi,

 

a beginner question: when there is GTM and LTM in the system, if we want to get an idea (via SNMP) about the amount of requests the associated LTM handles, we may perhaps sum ltmVirtualServStatTotRequests of that LTM; if we'd be ok with DNS only then there's ltmDnsProfileStatResponses, but based on "Overview of BIG-IP DNS request processing" I am unsure if that should be added to ltmDnsCacheStatResponses to get the total amount of responses (there also seem to be stats for other protocols), is this correct? Or is it possible some other way?

 

^ I'm aware there's a requests vs response difference, this is more about understanding what is available and how to understand the individual stats, so it's not overly exact question.

 

Thank you!

 

application delivery
BIG-IP
LTM
snmp
statistics

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  • StephanManthey's avatar
    StephanManthey
    Icon for MVP rankMVP
    Dec 04, 2015

    Hi Jiri,

     

    both GTM and LTM are using virtual servers to handle incoming requests.

     

    In case of GTM you create a so called listener object which is showing up as a virtual server in LTM as well. Each incoming DNS query will show up in this virtual servers statistics. A connection will represent a request. If you are GTM expecting to return multiple resource records upon request (by default a single record is returned only) you want to poll the dns profile statistics instead. I assume the cached responses are contained in these stats but I would recommend to cross check.

     

    For pure LTM virtual servers the http profile statistics will be relevant from my perspective. A client may use a keepalive connection to use an existing connection without outstanding responses for new requests. Thats why the connection counter of this type of virtual server tells very little about the number of handled requests. But these statistics are collected in the http profiles. In the bottomline you will get best statistics data from the dns and http statistics profiles in my opinion.

     

    Thanks, Stephan