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Basil_Parsley_1's avatar
Basil_Parsley_1
Icon for Nimbostratus rankNimbostratus
Feb 10, 2016

GTM Qs - Synch group / wide IP / licensing ...

Guys,

 

Some Qs which I have not found documented or have seemingly contradictory information for …

 

Q1. Can you add an LTM to a (GTM) configuration synchronisation group and what is the use case? My understanding is that only GTMs can be part of a config synch group however e.g. the GTM exam syllabus has the opposite.

 

Q2. GTM – can you add an iRule to a listener ? My understanding was you can only add to a wide IP – there is an option under virtual servers to do this – I am not 100% as to whether this is part of “hold over” config for LTM deployments.

 

Q3 On a VIPRION hosted vCMP licensed for LTM and GTM but only provisioned for GTM am I expected to see all the LTM configuration menu options? I had thought these become viewable only when provisioned …

 

Q4 DNS Services Licence – am I correct in saying even if you have a GTM licensed device you will still need this license for e.g. DNS caching?

 

Cheers.

 

application delivery
BIG-IP DNS

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  • IanB's avatar
    IanB
    Icon for Employee rankEmployee
    Feb 11, 2016

    Q1. GTM and LTM synchronisation are entirely unrelated and synchronise different objects. Most GTM objects are synchronised via gtm sync, but a notable exception to this is GTM listeners, since they are actually LTM virtual servers, are are unique to each individual GTM in any case (it wouldn't make sense to synchronise the listeners across the gtm sync group)

     

    Q2. You can add an iRule to a listener - it will be an LTM irule, which means it receives LTM events, as opposed to a wideip with an iRule which will receive GTM events, and is limited to commands that make sense to GTM.

     

    Q3. The GTM license enables certain LTM features behind the scenes in order to function properly. Different versions of BigIP act slightly differently in what you see in the GUI. If you have a GTM-only license, you'll be quite limited (and won't be able to add irules to listeners, for example)

     

    Q4. DNS services (DNS Express, DNS cachine) is actually part of the LTM license, not GTM, though it works with the GTM product via options turned on in the the GTM listener's DNS profile

     

  • Basil_Parsley_1's avatar
    Basil_Parsley_1
    Icon for Nimbostratus rankNimbostratus
    Feb 11, 2016

    Nice one Ian ... as usual you have answered the Qs I asked and the detail I did not ....

     

    Just clarifying A4. Are we saying I can enable this gratis on the LTM i.e. it is paid for under the LTM license and just needs activating? And GTM all I need to do is activate the options (caching / Express) under the profile and I have no ancillary licensing REQs over and above GTM license. (struggling to see the point of this as a separate license entity TBH if this is true ... )

     

    • IanB's avatar
      IanB
      Icon for Employee rankEmployee
      Feb 11, 2016
      Each purchased BigIP module or add-on turns on a set of flags in the license file. Those flags are what are actually checked, and any given flag could potentially be turned on through more than one SKU. This also changes with versions, and the good-better-best licensing model also changed the way a lot of this worked. With VCMP, the host is licensed, and the guests receive a copy of the license, so are able to enable any modules that the host is licensed for. The idea is that you could have a GTM vcmp guest, and a few LTM guests, and one with APM, or whatever combination the host is licensed for. I'm 90% certain that the SKUs we sell for "GTM" (which is now sold as BigIP DNS) all enable the LTM DNS feature flags, but if you want to be absolutely sure, you could talk to your account manager, or open a support ticket, as it would depend on the actual SKUs that you have purchased.
  • Basil_Parsley_1's avatar
    Basil_Parsley_1
    Icon for Nimbostratus rankNimbostratus
    Feb 11, 2016

    Cheers ; FYI looking at good better best DNS services sits squarely under "better" and GTM.. Anyway thanks for your help.... Case closed.