Cisco Systems OL-14619-01 manual Using Firewalls with Cisco Unity

Chapter 3 Network Infrastructure Requirements

Using Firewalls with Cisco Unity

during installation. If Cisco Unity subscribers are homed on servers other than the partner Exchange server or the Domino mail drop server, all voice messages from outside callers pass through the partner server or the mail drop server on their way to the home servers for Cisco Unity subscribers.

When the partner Exchange server, the mail drop Domino server, or a message store server on which Cisco Unity subscribers are homed is unavailable, Cisco Unity functionality is affected in the following ways:

•Messages from outside callers are stored on the Cisco Unity server in the Unity Message Repository (UMR), and can be retrieved during the outage. However, voice messages that were previously received by subscribers are not available until the home server is back online.

•When the home server of a calling subscriber is down, any messages from that subscriber are stored on the Cisco Unity server in the UMR, and can be retrieved by the recipient during the outage.

•Message waiting indicators and message notification will not work.

Tip Make sure that the importance of message store availability is clearly understood prior to installing one

or more Cisco Unity servers, particularly those that service message stores on separate servers.

Using Firewalls with Cisco Unity

Revised May 6, 2008

Cisco Unity can coexist with firewalls. However, note that Cisco Unity should never be deployed outside of a firewall. Doing so can expose the Cisco Unity server to unwanted intrusion from the Internet, even if the server is hardened.

For detailed firewall requirements, see the following sections in the System Requirements for

Cisco Unity at

http://www.cisco.com/en/US/products/sw/voicesw/ps2237/prod_installation_guides_list.html:

•“Network Requirements”

•“Failover Requirements for Separating Cisco Unity Servers by a Firewall”

•“Standby Redundancy Requirements for Separating Cisco Unity Servers by a Firewall”

Sizing and Scaling Cisco Unity Servers

When sizing a Cisco Unity server, follow these guidelines:

•Maximum Number of Users on Dedicated Domino or Exchange Servers, page 3-4

•Storage Capacity for Voice Messages, page 3-4

•Number of Voice Ports, page 3-4

For a list of servers that meet Cisco Unity specifications, see the Cisco Unity Supported Platforms List at http://cisco.com/en/US/products/sw/voicesw/ps2237/products_data_sheets_list.html.

Design Guide for Cisco Unity Release 5.x

OL-14619-01 3-3