gatekeeper redundancy from CCM perspective

[simmo]

Hi,

Firstly, I would like to confirm my understanding of gatekeeper redundancy, as the documentation is a bit confusing....

A) to provide a redundant gatekeeper from an 'endpoint-to-gatekeeper' perspective - ie H323 gateway, or CUCM cluster, this can only be done by

     1) - using HSRP address on the gatekeepers

     2) - using a multicast registration address

B) to provide 'redundnant gatekeeper' in a 'gatekeeper-to-gatekeeper' perspective - can be done by:

    1) using H323 zone support - ie blast / seq config

    2) using Zone Cluster configuration

Can someone let me know if I'm on the right track here?

Lastly, what I really want to do is have a Gatekeeper controlled Intercluster Trunk, between 3 CUCM clusters, using 2 gatekeepers for redundancy - ie each gatekeeper should be capable of doing the job on its own. As the gatekeepers are in different locations, HSRP and Multicast are not options. I am thinking that the only way to achieve this to create 2 trunks, 1 to each gatekeeper, and use a Route Group / Route List to achieve redundancy, and possibly load balancing.

Thanks!

[William Bell]

Here is the link to the section within the CUCM SRND concerning gatekeeper redundancy.  In versions prior to cm 3.3 the method of choice was using HSRP (actually the only option at the time).  With later releases gatekeeper clustering (aka alternate gatekeeper) is supported.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/7x/callpros.html#wp1044182

The example Cisco provides gives a good explanation of how to integrate alternate gatekeeper.  You can have up to 5 gatekeepers in a gatekeeper cluster and you configure the CUCM cluster to use a primary and one or more alternate.  No multicast and no HSRP required.

HTH.

Regards,
Bill

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[simmo]

Hi Bill,

thanks for your answer. I should have looked at the SRND... too busy looking at the

IOS design guides.

Can I go a bit deeper - with the suggested configs in the SRND, should my CUCM clusters only have a single trunk configured to the nearest GK, and if so how does the CUCM server know how to get to the backup GK if the first one fails?

thanks again! Mark.