Cisco Systems OL-14619-01 manual Standby Redundancy

Chapter 7 Cisco Unity Failover and Standby Redundancy

Standby Redundancy

Configuring Failover When Cisco Unity Servers Are Separated by a Firewall

Revised May 6, 2008

When Exchange is the message store, you can separate Cisco Unity primary and secondary servers by a firewall. When IBM Lotus Domino is the message store, the primary and secondary servers cannot be separated by a firewall.

If the system includes a Cisco Unity voice recognition server, the primary and secondary Cisco Unity servers must be on the same side of the firewall as the Cisco Unity voice recognition server.

For additional requirements, see the “Failover Requirements for Separating Cisco Unity Servers by a Firewall” in the System Requirements for Cisco Unity at http://www.cisco.com/en/US/products/sw/voicesw/ps2237/prod_installation_guides_list.html.

Installing Exchange 2003 on the Cisco Unity Secondary Server in a Voice Messaging Configuration with Failover

When Cisco Unity failover is installed in a Voice Messaging configuration, Exchange Server 2003 can be installed on the secondary server instead of on a separate, third server. Requirements for this configuration are listed in the “Requirements When the Message Store Is Installed on the Secondary Server” section of the System Requirements for Cisco Unity Release 5.0 at http://www.cisco.com/en/US/products/sw/voicesw/ps2237/prod_installation_guides_list.html.

Requirements for Spanning a Cisco Unity Failover Pair Across Redundant Data Centers

Revised May 6, 2008

Some customers maintain redundant data centers that are so well connected that they essentially form a single LAN. For these customers, failover may be a more suitable configuration than standby redundancy. For detailed requirements for this configuration, see the section “Failover Requirements for Separating Cisco Unity Servers by a WAN” in the System Requirements for Cisco Unity at http://www.cisco.com/en/US/products/sw/voicesw/ps2237/prod_installation_guides_list.html.

Standby Redundancy

Note the following about a Cisco Unity system configured for standby redundancy:

•The standby redundancy configuration requires a minimum available bandwidth of 100 Mb/second between the data centers in which the Cisco Unity primary and secondary servers are installed. This is because of two bandwidth spikes, one caused by SQL Server, the other by Cisco Unity:

–Once daily (by default at 2:00 a.m.), SQL Server replicates data from the active server to the inactive server.

–Cisco Unity periodically replicates WAV files of voice names, greetings, call handlers, and interview handlers from the active server to the inactive server.

•If something happens to the data center in which the Cisco Unity server is installed, the customer must have:

–A way to reroute call traffic to the data center in which the secondary server is installed.

Design Guide for Cisco Unity Release 5.x

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