CUCM Clustering and Group question

[warquezho0612]

I've read that a cluster can support up to 20 nodes/server and that only 8 nodes/server are callmanager, the others maybe a unity or ccx or presense etc.

Are the 8 nodes all subscriber or the publisher is included in the 8 nodes? If the 8 nodes are all subscriber then add the publisher there will be a total of 9 nodes per cluster? I think this is for CUCM 6/7. Does this still hold true for CUCM 8 and beyond?

I've also read that call manager group can only have a total of 3 CUCM per group? Is this true? As I have no experience configuring more than 3 CUCM. If it does, how about in future releases, will the number increase or will remain at 3 CUCM per call manager group?

Thanks,

Mark

[Rob Huffman · Accepted solution]

Hi Mark,

An excellent resource for these design questions is the SRND. Here is the related

info for CUCM 8.x;

General Clustering Guidelines

The following guidelines apply to all Unified CM clusters:

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Note A cluster may contain a mix of server platforms, but all servers in the cluster must run the same Unified CM software release.

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•Under normal circumstances, place all members of the cluster within the same LAN or MAN.

•If the cluster spans an IP WAN, follow the guidelines for clustering over an IP WAN as specified in the section on Clustering Over the IP WAN, page 2-21.

•A Unified CM cluster may contain as many as 20 servers, of which a maximum of eight call processing subscribers (nodes running the Cisco CallManager Service) are allowed. The other server nodes within the cluster may be configured as a dedicated database publisher, dedicated TFTP subscriber, or media resource subscriber.

•When deploying Unified CM on Cisco MCS 7815, MCS 7816, or equivalent servers, there is a maximum limit of two servers in a deployment: one acting as the publisher, TFTP, and backup call processing subscriber node, and the other acting as the primary call processing subscriber. A maximum of 500 phones is supported in this configuration with a Cisco MCS 7816 or equivalent server.

•When deploying a two-server cluster with high-capacity servers, Cisco recommends that you do not exceed 1250 users in the cluster. Above 1250 users, a dedicated publisher and separate servers for primary and backup call processing subscribers is recommended.

•Unified CMBE 3000 8.5(1) runs on the MCS 7816 server platform, while Unified CMBE 3000 8.6(1) and later versions run on either the MCS 7816 or the MCS 7890-C1 purpose-built appliance. In either case Unified CMBE 3000 provides a single instance of Unified CM (a combined publisher and single subscriber instance). A secondary subscriber instance is not configurable.

•Unified CMBE 5000 runs on a single hardware platform (MCS 7828), and it provides a single instance of Unified CM (a combined publisher and single subscriber instance). A secondary subscriber instance is not configurable.

•Unified CMBE 6000 runs on a UCS C200 Rack-Mount Server and provides a single instance of Unified CM (a combined publisher and single subscriber instance). An additional UCS C200 server may be deployed to provide subscriber redundancy either in an active/standby or load balancing fashion for Unified CMBE call processing as well as other co-resident applications. Cisco recommends deploying redundant servers with load balancing so that the load is distributed between the two UCS C200 servers. Alternatively an MCS server can be used to provide Unified CM subscriber redundancy either in active/standby or load balancing fashion.

•When deploying Unified CM on Cisco UCS B-Series or C-Series Servers, just as with a cluster of MCS servers, each Unified CM node instance can be a publisher node, call processing subscriber node, TFTP subscriber node, or media resource subscriber node. As with any Unified CM cluster, only a single publisher node per cluster is supported.

•While the Cisco UCS B-Series Blade Servers and C-Series Rack-Mount Servers do support a local keyboard, video, and mouse (KVM) cable connection that provides a DB9 serial port, a Video Graphics Array (VGA) monitor port, and two Universal Serial Bus (USB) ports, the Unified CM VMware virtual application has no access to these USB and serial ports. Therefore, there is no ability to attach USB devices such as audio cards (MOH-USB-AUDIO=), serial-to-USB connectors (USB-SERIAL-CA=), or flash drives to these servers. The following alternate options are available:

–For MoH live audio source feed, consider using Cisco IOS-based gateway multicast MoH for live audio source connectivity or deploying one Unified CM subscriber node on an MCS server as part of the Unified CM cluster to allow connectivity of the USB MoH audio card (MOH-USB-AUDIO=).

–For SMDI serial connections, deploy one Unified CM subscriber node on an MCS server as part of the Unified CM cluster for USB serial connectivity.

–For saving system install logs, use virtual floppy softmedia.

As for the CCM Group question, each CCM Group can still only contain 3 CUCM but of course

you can configure multiple CCM Groups within the cluster. There are some good notes on this from the same

SRND;

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/callpros.html#wp1151647

Cheers!

Rob

[warquezho0612]

Hi Rob,

Thanks for the reply, I'am ok with the callmanager group.

Just to clarify you color blue statement, so that  means I can have a subscriber and 1 publisher call procesing cucm in a  cluster, so that would be 8 cucm all in all? And the others 11 can be  unity connection, presense or uccx?

Regards,

Mark

[Rob Huffman]

Hi Mark,

It could be 8 call processing Subscribers plus a Publisher that does

not run the Callmanager service. In the number 20 it would not include

Unity connection, UCCX or Presence. Those are outside of the number

completely

Cheers!

Rob

[Marwan ALshawi]

Just to add to Rob's post. 5 +

the 8 servers as a max with call manager services enabled are used for call processing

While others with call manager service disabled can be used for other functions such as TFTP, MOH ..etc

Note: a cluster can have more than 8 servers for call processing and called mega cluster and this has to be certified from Cisco for large deployments

Hope this help

If helpful rate

[warquezho0612]

Oh I get it, that 20 server is for CUCM only, and a max of 8/20 server can be used for call processing, others can be used as a tftp, media resource CUCM server. Unity connection, Presense, Uccx not included.

How about for unity connection, presense, uccx? is it also 20 maximum server each per cluster?

[Marwan ALshawi]

That's correct

For other UC clusters such as ccx max of two servers works in active standby

Presence and unity connection have different concept you can refer to each UC application design doc for more details

Hope this help

Plz rate the helpful posts

[warquezho0612]

Thanks marwanshawi!

[KY_]

Hi Rob,

In this link; http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/srnd/8x/uc8x/callpros.html#wp1151374

It seem maximum 16 subscriber per mega cluster but that you say eight subsriber per one cluster.

which one is correct.Can you please  explain difference between two subsject.

Thanks

[Abhishek Ranjan]

We can have Call Manager service running only on 8 servers and can have 1:1 redundancy/failover which makes it 16 and 2 MOH servers, 2 TFTP server, and 1 Publisher. So, in total 20 servers with 1 publisher.