Introduction
This document describes the options available when required to restore the Cisco Unified Instant Messaging and Presence (IM&P) Publisher and Subscriber nodes.
If you have a Disaster Recovery System (DRS) backup or Contact List backup, you can rebuild the IM&P nodes without the need to restore the entire cluster.
Contributed by Pradeep K Vaka, Feng Gao, and Miguel Castillo, Cisco TAC Engineers.
Problem
If there is a requirement to restore IM&P Publisher and Subscriber after a rebuild, there are steps to avoid the need to restore the full Cisco Unified Communications Manager (CUCM) and IM&P cluster.
Otherwise, the Cisco Sync Agent service does not start due to the known Cisco Bug ID CSCuo02154.
This solution outlines the steps required to avoid the known problem where the Cisco Sync Agent service fails to start.
Solution
Note: It is recommended to maintain a DRS backup of the cluster and a copy of exported Contact List from the IM&P server separately.
Option 1. If you do not have a Contact List backup or if you need to restore DRS backup, follow the next methods based on your IM&P system version.
a) If your IM&P version is 10.5.2.22900 or later:
- Do not delete IM&P server entries on CUCM (System > Server) page.
- Rebuild IM&P Publisher and Subscriber nodes.
- Restore DRS backup of IM&P nodes only.
b) If your IM&P version is earlier than 10.5.2.22900, which does not include the fix for Cisco Bug ID CSCuo02154:
- Do not delete IM&P server entries on CUCM (System > Server) page.
- Open a TAC Service Request to perform the workaround on CUCM (via root access) for Cisco Bug ID CSCuo02154.
- Rebuild the IM&P Publisher and Subscriber nodes.
- Restore DRS backup of the IM&P nodes only.
Option 2. If you have the Contact List backup and you do not have a good DRS backup to restore, then perform these steps:
- Delete the IM&P server entries on CUCM (System > Server) page.
- Re-add the IM&P server entries on CUCM (System > Server) page.
- Rebuild the IM&P Publisher and Subscriber nodes.
- Perform the basic integration steps such as activate services, add Presence Gateway, and so on.
- Import the Contact List.
Caution: If you remove the CUCM IM and Presence server entries from CUCM System > Server page and then perform a fresh install of the IM&P nodes, you must restore the DRS backup of the entire cluster (all CUCM and IM&P nodes). If you only restore the IM&P nodes after the fresh install, the database primary keys do not match on CUCM, and the IM&P processnode tables and the Cisco Sync Agent service do not start.
Considerations
- The Contact List is not backed up with the DRS backup, as it requires to be exported from the IM&P Administration page. Once the IM&P Servers have been reinstalled, the contact list cannot be retrieved.
- Navigate to Bulk Administration> Contact List > Export to export the Presence Contact lists.
- Navigate to Bulk Administration> Non-presence Contact List > Export to export the Non-Presence Contact lists.
- The IM&P Publisher cannot be backed up from the IM&P Subscriber node, nor an IM&P Subscriber can be promoted to an IM&P Publisher, meaning, if the IM&P Publisher fails, it requires to be rebuilt.
- If only one node requires to be reinstalled, follow the next steps.
- Reinstall only the IM&P Publisher:
- Step 1. Disable the High Availability. Navigate to CUCM Administration page > System > Presence Redundancy Groups > Click Find > Select the presence redundancy group > Uncheck the High Availability checkbox > Click Save.
- Step 2. Turn off the IM&P Subscriber node.
- Step 3. Reinstall the IM&P Publisher (Do not remove the Server entries from the CUCM).
- Step 4. After the IM&P Publisher is reinstalled, activate the required services.
- Step 5. Turn on the IM&P Subscriber node and validate that all the services are started.
- Step 6. If you would like to validate that the database replication is configured correctly run the command utils dbreplication status, wait some minutes and then run utils dbreplication runtimestate on the CLI of the IM&P Publisher.
- Step 7. If the command shows (-) Not Setup, run the command utils dbreplication rebuild all from the IM&P Publisher's CLI after hours.
- Reinstall only the IM&P Subscriber:
- Step 1. Disable the High Availability. Navigate to CUCM Administration page > System > Presence Redundancy Groups > Click Find > Select the presence redundancy group > Uncheck the High Availability checkbox > Click Save.
- Step 2. Reinstall the IM&P Subscriber (Do not remove the Server entries from the CUCM).
- Step 3. After the IM&P Subscriber is reinstalled, activate the required services and ensure all the services run well.
- Step 4. If you would like to validate that the database replication is configured correctly run the command utils dbreplication status on the IM&P Publisher's CLI.
Note: If the next error is displayed: "Attention: Status command cannot be executed because no active connected replication servers are currently available", run the command utils dbreplication reset all on the IM&P Publisher's CLI and proceed with step 4 after some time to validate if the database has replicated correctly between the nodes.