How Cisco IT Migrated 87,000 Voicemail Boxes in a Weekend

November 4, 2011 - 3 Comments

Changing voicemail systems–or the servers they run on–can be a big, time-consuming, and difficult task. Yet recently we did both.  We migrated our application platform from Cisco Unity 7.0 (2) running on Cisco 7800 Series Media Convergence Servers,  to Cisco Unity Connection 8.5 running as a virtual machine onthe Cisco Unified Computing System (UCS) platform. What’s more, we completed the cutover of more than 87,000 voicemail boxes to the new platform in a single weekend.

Making two big changes at the same time might seem risky, but in fact, that’s what made the migration successful. We were able to do the preparation work first deploying new UCS servers, next installing Cisco Unity Connection software on the new servers, and finally by replicating the user mailbox configurations onto the new platform.  Then, for the actual migration we simply cut-over to the new servers by changing the call routing.
A few important decisions also made our work easier.For most users, we decided not to migrate their saved messages, instead keeping them available on the old servers for 30 days. We also decided not to migrate most group distribution lists because so few were actively used. For the user accounts and messages that we actually migrated, we used the standard tools that come with Cisco Unity Connection, and they made the job a lot easier.
In the two months since the cutover, we haven’t had any major problems or performance issues with the new environment. The change to a new voicemail system was also smooth for our users; our internal help desk received far fewer support cases than were expected during the first week.  The only thing that most people noticed was a change in the recorded voice they heard when getting their voicemail messages.
As the engineer in charge of our Unity Connection voicemail service, the new platform is a brilliant change in almost every aspect.  The scalability of the UCS platform coupled with full virtualization significantly simplifies installation and maintenance of the systems and allows us to do on average four times the UC work load in the same physical space. The active-active operation of the UCxN server pairs ensures that maintenance can be done without any interruption of service at all and actually improves reliability over our previously rock-solid Unity. On our largest location, with nearly 25,000 active mailboxes were able to migrate from 8 nodes in our old environment to only 2 nodes and still have enough room for another 50% growth.

The engineers managing the data center are much happier too as we are now able to fully leverage their standardized environment (thanks to virtualization on the UCS platform) while reducing our hardware footprint – along with power and cooling requirements – by nearly 80% over our previous footprint. Our migration to virtual servers also makes the voicemail services more fault tolerant and resilient, which leaves us with fewer problems to look forward to in future.

Read more about this migration in the full Cisco Unity Connection on UCS case study.

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  1. How did Cisco encourage their staff to go for blogging?

  2. I cannot get the link to case study to work. Can you check it?