CME redundancy with E1 line

[jean_sarkis]

Good morning,

I have a Call manager (Cisco router 3845) with the following characteristics :

- Product number : C3845-IPVOICEK9-M

- IOS : c3845-ipvoicek9-mz.124-15.T7.bin

- 2 Gigabit Ethernet interfaces

- 2 Channelized (E1 or T1)/PRI ports

So my questions are :

- For the backup Call Manager express can we use the router Cisco 3945 (C3945-CME-SRST/k9 ) ?

- The 2 routers (CME and CME backup) have to be the same (same hardware and same software) ?

- Cisco documents shows redundancy with FXO lines (we used a Splitter) what about redundancy with E1 lines ?

Thank you.

[Manish Prasad]

Check this excellent post by Rob.

https://supportforums.cisco.com/thread/2070193

Rate all the helpful post.

Thanks

Manish

[Manish Prasad]

what about redundancy with E1 lines - you need E1 fail-over switch , search on Internet you will find many product.

Dont forget to rate all the helpful post.

Thanks

Manish

[Nadeem Ahmed]

Hi Jean,

- For the backup Call Manager express can we use the router Cisco 3945 (C3945-CME-SRST/k9 ) ?

[Ans]: Yes but the IOS version should be same.

- The 2 routers (CME and CME backup) have to be the same (same hardware and same software) ?

[Ans]: Only Software version should be same

- Cisco documents shows redundancy with FXO lines (we used a Splitter) what about redundancy with E1 lines ?

[Ans]:

When you are creating any DN on CME it creates a virtual dial-peer  which you cannot modify - you can review all the dial-peers into the  system using 'sh dial-peer voice summary'. Such dial-peers are numbered  with 5digits and you cannot access them to modify.

So make another  dial-peer with the same destination-pattern but with higher preference.  When the phones are not registered it will be forwarded to next  preference and it works.

Example :

Lets suppose we have 1-PRI on CME1 and another PRI on CME2

when a call come from pstn on CME2 PRI [Secondry router] , it should find the phone not registered

then to forward the call to CME1 using voip dial-peer

dial-peer voice 5000 voip
destination-pattern 5...$

session target ipv4:CME1.ip.add

dtmf-relay h245-alphanumeric

no vad

Also i found a very good link of google:

http://iwouldratherwatch.blogspot.jp/2008/08/redundant-cme-configuration.html

Br,
Nadeem 

Please rate all useful post.

[jean_sarkis]

Hi Nadeem,

Thank you for your answers.

I still have some questions to ask:

- The IOS version for Cisco 3945 is : 15.2(4)M and for Cisco 3845 is : 12.4(15)T7 .So my question is can we upgrade the IOS version of Cisco 3845 to the IOS version 15.2(4)M ?

- In the link that you send me , in the first picture it is correct that the service provider is providing the same number on two differents E1 lines ?

Thank you

Jean Sarkis

[Nadeem Ahmed]

The latest ios version for 3845 is 15.1(4)M7... so i would recommend to find same version for 3945..

Yes in that link PSTN is providing same number..

Br,
Nadeem 

Please rate all useful post.