CUCM in a cluster and redundancy

[sarahr202]

Hi everybody.

Please consider the following example:

                                   (1-100 phones)-----CM1------PUB-----CM2(101-200)

CM1 controls 1-100 phones; CM2 controls 101-200 phones. Publisher is not controlling any phones

My question is how does Cluster provide redundancy if CM1 goes down ?

I am just going on my  hunch here.

1-100 phones uses Call manger group as"

CM1

CM2

So after phones in 1-100 group does not receive the response from CM1 for keep alive, phones in 1-100 group contact the Cm2 and register with them.

Is this how we provide redundancy in a cluster?

thanks and have a great day.

[Suresh Subramanian]

Pls check this system guide URL:

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/8_0_1/ccmsys/a02redun.html#wp1020927

[Jaime Valencia · Accepted solution]

Yes, via the CUCM group in which you define up to 3 servers in order of preference.

HTH

java

if this helps, please rate

www.cisco.com/go/pdihelpdesk

[Chris Deren · Accepted solution]

In addition to correct answers by my colleagues here, when building CM groups you need to obey few rules which are described in SRND. I realize your environment is small so this may not apply, but it is important to know of future.

• Cisco only supports 1:1 and 2:1 redundancy model, I see all kinds of unsupported deployments that end up in N:1 model, this leads to potential overload of backup servers.  Pay special consideration when clustering across WAN.
• Yon need to ensure that the backup server is as powerful or more than the primary call processor it back up.
• You should not be running CM process on Pub for environments with over 1250 devices.

HTH,

Chris