MGCP E1 Register - Unregister to CCM

Unanswered Question
Oct 19th, 2007
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Hello There,

We are using CCM 5.1.2 and 2851 voice gateway with E1. E1 normally registered to CCM with MGCP. Last week E1 registered and unregistered abnormally. We restarted CCM and router but nothing changed. E1 is running with H.323 now. Configuration is like that,

isdn switch-type primary-net5


controller E1 0/3/0

pri-group timeslots 1-31 service mgcp


interface Serial0/3/0:15

no ip address

encapsulation hdlc

isdn switch-type primary-net5

isdn incoming-voice voice

isdn bind-l3 ccm-manager

no cdp enable


ccm-manager redundant-host

ccm-manager mgcp

ccm-manager music-on-hold

ccm-manager config server

ccm-manager config



mgcp call-agent 2427 service-type mgcp version 0.1

mgcp dtmf-relay voip codec all mode out-of-band

mgcp rtp unreachable timeout 1000 action notify

mgcp modem passthrough voip mode nse

mgcp package-capability rtp-package

no mgcp package-capability res-package

mgcp package-capability sst-package

no mgcp package-capability fxr-package

mgcp package-capability pre-package

no mgcp timer receive-rtcp

mgcp sdp simple

mgcp fax t38 inhibit

no mgcp explicit hookstate

mgcp rtp payload-type g726r16 static


mgcp profile default


dial-peer voice 999020 pots

service mgcpapp

port 0/3/0:15



secondary-dialtone 0

max-conferences 8 gain -6

transfer-system full-consult

ip source-address port 2000

max-ephones 30

max-dn 30

Why we couldn't run E1 with MGCP? Any idea?

Thanks for your help.

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Anonymous (not verified) Thu, 10/25/2007 - 07:21
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You may be hitting with a bug : check the details of this one : CSCeh13683

Ayodeji Okanlawon Thu, 10/25/2007 - 08:36
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To resolve this, you will need to simulate the problem again.

debug mgcp packet...look at the response codes mgcp returns...something like 200, 400, 500...

stop mgcp and restart mgcp with no mgcp and mgcp with debug mgcp packet on...

capture the mgcp exchane betwen ccm and gateway.

use sh ccm-manager to see the domain name returned and check its the same as what you have configured on CCM.

Also try and ping the FQDN of the gateway from the CCM server..

allan.thomas Thu, 10/25/2007 - 15:14
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One aspect that you need to consider which concerns MGCP is which interface MGCP is using for its source address?

Typically MGCP defaults to the loopback if configured unless a different interface is specified as the source.

Your configuration does not specifically indicated an MGCP source-interface, therefore if you have multiple IP interfaces then you need to determine which address is used by MGCP. The command show ip socket should indicate port 2427 and the source address. Is this address reachable by CallManager.

I would recommend that you configure or specify a specific MGCP source-interface, this will avoid an incorrect source address being selected.

Please bear in mind that when you specify a source-interface which is not a loopback, then it highly probable that after the gateway is reloaded MGCP will be unable bind to a physical interface unless the operational status is UP.

I have also come across issues with registration unless you specify the network-clock-participate command. Ordinarily this should not be necessary, however on 12.4.9(T2) when the configuration fails to download, I configure the clock command, remove and re-apply mgcp as stated in the previous post and then registration is successful.



I have seen this issue a few times and everytime I have seen it I have removed the 'ccm-manager config server x.x.x.x' command and it seems to be fine after that.

A bunch of other guys I work woth ahve had the same issue and done the same remove the config server and all was okay.

it seems to work for the initial install but for some reason after a while the t1 or e1's either just stop working or the config actually disappears..

Thats been my experience


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