IP Manager Assistant (IPMA) - Shared Line Mode

        IP Manager Assistant (IPMA) provides better support, visibility, and control between a Manager and an Assistant or multiple Assistants. There are two ways of configuring IPMA. The first being Proxy Mode and the second being shared-line mode. 

Configuring Shared Line Mode

1. Configure the Manager phone and Assistant(s) phones with a shared line appearance.
2. In Cisco Unified Serviceability, activate the Cisco IP Manager Assistant service in the Service Activation window.
3. Configure Cisco IP Manager Assistant service parameters for shared line support
1. Clusterwide Parameters (applies to all servers)
1. In CM Administration go to System > Service Parameters
1. Choose the IPMA server and choose the CIsco IP Manager Assistant Service
2. Cisco IPMA Server (Primary) - up to 2500 managers and assistants
3. Cisco IPMA Server (Backup)
4. Cisco IPMA Server Port - Default Port 2912
5. IPMA Heartbeat Interval - Time for failover to occur (default is 30 seconds)
6. IPMA Assistant Console Request timeout - Default is 30 seconds
2. Advanced Clusterwide
1. Enable Multiple Active Mode - default is false. If true, both IPMA servers are used and up to 7000 managers and assistants can be used via multiple pools
2. Pool 2 - IPMA Server (Primary) - 2500 users here
3. Pool 2 - IPMA Server (Backup)
4. Pool 3 - IPMA Server (Primary) - 2500 users here
5. Pool 3 - IPMA Server (Backup)
3. IPMA Service Parameters (for each server)
1. CTIManager (Primary) IP Address - used for call control
2. CTIManager (Backup) IP Address
4. Restart the IPMA Service for the changes to take effect
5. In CM Administrator go to User Management > End User
6. Start with the Manager
1. Verify that he/she is associated with their phone
2. Under Related Links, select Manager Configuration
3. Configure the device, intercom, shared lines, and assistant(s)
4. Once the Manager is setup, their phone will reset with IPMA features on the phone
7. Configure the Assistant
1. Verify that he/she is associated with their phone
2. Under Related Links, select Assistant Configuration
3. Configure the device, intercom, primary line, managers, and manager lines
8. You can setup dial rules (prepend 9) for the IPMA
9. Download and install Cisco Unified Communication Manager Assistant
1. If running Windows 7, download through Cisco CallManager Updates
10. Install and login with the correct IPMA server IP address, username and password

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/8_6_1/ccmfeat/fsipmasl.html#wp1288368

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