Using SLB to provide Extension Mobolity redundancy

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May 15th, 2008
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Hi there,

I would like to use SLB to provide Extension Mobility redundancy in CUCM 6.1 as per the URL

Does anyone have any sample configs for the SLB part please? (Going to use Cat65k running IOS)



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Anonymous (not verified) Wed, 05/21/2008 - 05:48
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In order to provide redundancy for the Cisco CallManager Cisco IP Phone Services (or URL Services) and the EM phone service components, Cisco recommends using the Server Load Balancing (SLB) feature available in Cisco IOS to front-end multiple Unified CM nodes. The Cisco IOS SLB feature provides a virtual-IP-to-real-IP address mapping, that front-ends the real IP addresses of the Unified CM nodes. The SLB feature can be configured to monitor the status of multiple nodes, automatically redirecting requests during failure events. By using the SLB virtual IP address (or DNS hostname) for the URL Services and EM IP phone service, you can ensure that both components are still available during any node failure and, therefore, EM login and logouts will continue.

davidstevenscisco Wed, 05/21/2008 - 05:57
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Hi, thanks but I had already read these. I have since developed a test lab and prototyped the solution so I now have my own configs.

It works but there is a delay of about 2 mins when the Publisher is offline. I guess that the Subs are timing out writing to the Pub


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