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New Member

Unity database in a cluster

When we have a Unity cluster, how does Unity maintain its database? Is there a Publisher <-> Subscriber sort of relationship maintained?

Cisco Employee

Re: Unity database in a cluster

You don't "cluster" Unity servers per se... we support a "failover configuration" with two boxes. It's a hot failover system and yes, it uses SQL replication between the two servers to keep things up to date. There's also a failover replication service installed that keeps items not in the SQL database (i.e. some registry settings and greeting files on the hard drive etc...) synchronized between the two servers.

Here's the admin guide on failover that may be helpful as well:


Re: Unity database in a cluster

To add; Unity doesn't use the publisher / subscriber model like CallManager does. With Unity, both instances of SQL are read / write and the changes are merged. With CallManager, the publisher is read / write and all subscribers are read only. The difference is that most moves, adds and changes can be performed on the failover Unity server when the primary is down. For CallManager, no moves, adds and changes can be performed when the publisher is down.

New Member

Re: Unity database in a cluster

Thanks for the information

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