Extension Mobility users in SRST fallback

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Jul 16th, 2010
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Is it possible to configure an SRST router to map phones' mac addresses to static DNs?

The problem is that the phones are configured for extension mobility in normal operation. But, when the WAN link fails, users who are not yet logged in cannot do so. I understand this is expected behaviour.

Note:- Using CME SRST backup is not a desirable solution due to it involving a more complex configuration with 2 databases.

If the above mac based workaround is not possible, I would appreciate any alternative suggestions.


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Jaime Valencia Fri, 07/16/2010 - 07:03
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CME as SRST is precisely what you would need:

When a phone registers for SRST service with a  Cisco Unified CME router and the router discovers that the phone was  configured with a specific extension number, the router searches for an  existing prebuilt ephone-dn with that extension number and then assigns  that ephone-dn number to the phone. If there is no prebuilt ephone-dn  with that extension number, the Cisco Unified CME system automatically  creates one. In this way, extensions without prebuilt configurations are  automatically populated with extension numbers and features as the  numbers and features are "learned" by the Cisco Unified CME router in  SRST mode when the phone registers to the router after a WAN link fails.


Just SRST does not allow you to pre-configure the ephone-dn config.



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