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CME - SRST Fallback Support - Phone Firmware


I have a doubt with regards the behaviour/configuring of the phones in SRST Fallback Mode within CME.

When a phone that has an specific firmware (as per CM configuration) registers with CME, what happens?

Does it upgrade its firmware to the version stated in the configuration of the CME?

For example, for 7940 phones I would have on the CME router:

tftp-server flash:P00308000400.loads

load 7960-7940 P00308000400

If so, what happens when the CM Servers are back up, do the phones upgrade their firmware once again?

This is something I'd like to know in advance prior to deploy it.

Also, I saw a post regarding problems with the MGCP and the dial-peers used by CME.

is there any specific order in which the IOS make the digit matching? see the post below

Thanks for your cooperation.



IP Telephony: Issue with SRST Fallback with CME and dial peers

Posted by: crougeau - Apr 10, 2007, 8:16am PST

Here is my network setup. Remote site router configured as a MGCP gateway for local calls as well as CME using SRST fallback for emergency services. In normal operations LD calls traverse the WAN and utilize a dedicated T1 pri at a HQ location.

Here is my issue. An analog phone connected to a FXS port will use the local dial peer after a fail over has occured and returned to normal. The issue appears to be the order of the dial peers. Before failover the local pots dial peers were inserted after the MGCP dial peers. In this scenario LD calls placed from the analog set use the MGCP dial peers and LD calls are placed out of a centralized LD pri.

After failover and return to normal state, the order of the dial peers on the router are being reversed. I assume this is because the gateway has registered and the configuration, including the MGCP dial peers, has been pushed to the gateway. If I place a LD call at this point, the calls are routed out the local FXO ports because of pots dial peers that are used during failover.

Is this an issue or operating as designed? Should I be disabling ccm config to prevent this from happening or is there another way to prevent this scenario. Thanks