Cisco UC design and upgrade questions.

[Ryan Schwab]

Hi All,

I'm looking for advice/opinions on a UC solution I am proposing for an upgrade/refresh of an existing environment.

Currently:

• CUCM 4.2.3 cluster x3 nodes
  
• CCX 4.05 HA cluster
• Emergency Responder 1.3 single server
• Unity 4.2.1 single server Unified Messaging w/Exchange

This is a centralized multi-site deployment located in one data center. There are approximately 700 registered endpoints.

The requirements for the upgrade were left general enough:

• Provide redundancy between two major data centers (seperated West and East)
• Double capacity in 3 years (~1400 users)
• Linux appliance where possible

The data centers are connected via 100Mbps connection over QoS enabled link. The RTT between dc's is approx 45ms.

Proposed solution:

• CUCM clustered over the WAN (spec'd to meet capacity and redundancy requirements)
• CCX 8 clustered over the WAN
• Unity Connection 8 clustered over the WAN
• Emergency Responder 8 cluster in West DC.

A rebuild from scratch approach is accepted as the current implementation is somewhat of a mess.

Questions:

What is the feel for CUCM 8.0 in regards to bugs in a .0 release? Am I safer to go with 7.1.5? There are no features in 8.0 that are currently needed.

Clustering over WAN...given that the DC's are connected by a solid 100Mbps QoS pipe, should I have any concerns with this design for CUCM, CCX and CUC?

General opinions/comments on major gotcha's to look out for?

Any and all advice/comments is very much appreciated!!

[Jonathan Schulenberg]

What is the feel for CUCM 8.0 in regards to bugs in a .0 release? Am I 
safer to go with 7.1.5? There are no features in 8.0 that are currently 
needed.

UCM 8 has thus far proven stable where I am using it. If you want to use the 7.1 train instead you should choose the latest 7.1(3) build. The 7.1(5) version can not be upgraded until the 8.5 release.

Clustering over WAN...given that the DC's are connected by a solid 100Mbps QoS pipe, should I have any concerns with this design for CUCM, CCX and CUC?

You should be fine; just be sure to mark the intra-cluster signaling traffic properly to guarantee it the necessary bandwidth for proper replication.

General opinions/comments on major gotcha's to look out for?

1. Unity Connection 8.0 does not support true single-inbox unified messaging. The Outlook clients require a separate IMAP mailbox.
2. CCX failover is a warm-standby cluster. If you fail over, all calls in queue will be dropped; the outage is roughly one minute. Just set expectations appropriately.
3. CCX 8 is a major platform change (Windows to Linux). Very large chunks of the code were rewritten from scratch. Be prepared for a few bugs.