Moving CommCell Operations to Standby CommServe Host: Basic Failover

If your CommServe database and logs are regularly protected on a dedicated standby CommServe host, when the production (active) CommServe host becomes unusable or inaccessible, you can fail over the CommCell operations to the standby (passive) CommServe host.

In a non-disaster scenario, if you want to move your CommCell operations to standby host and use the standby as the production for a long period of time, you can perform a planned manual failover.

Before You Begin

Review the following requirements:

Procedure

  1. Update the DNS records to change the IP address of the floating CommServe name.

    Delete the current floating CommServe entry and add a new entry with the IP address of the standby CommServe host. See Deleting a DNS A Record and Creating a DNS A Record.

    Note: You can also create a prescript to update the DNS records and update the preStartScript parameter in the cvfailover.cfg configuration file.

  2. From the Start menu on the standby CommServe host, right-click the Command Prompt and then click Run as administrator.
  3. At the command prompt on the standby CommServe host, go to Installation_Directory_Of_Second_Instance /cvfailover, and type the following command:

    cvfailover /RunCriticalFailover

    1. Enter your local SQL Server Authentication user account having sysadmin capabilities.
    2. Enter the password for the local SQL Server Authentication user account.

      Note: If the password contains special characters, prefix each special character with an escape character or enter the password within quotes ("). For example, "test&2%" or test^&2%%.

      The following table lists the escape sequence for commonly used special characters.

      Special Character Escape Sequence
      ; ^;
      & ^&
      % %%
      , ^,
      . \.

      For more information on using escape characters, consult Microsoft documentation.

  4. If failover was performed to recover from a disaster, you must resynchronize the Deduplication Databases (DDBs).
  5. After restoring the CommServe database, any DDBs that are inconsistent with the CommServe database are flagged into maintenance mode automatically. Therefore, you must synchronize the inconsistent DDBs to reusable state. See Resynchronize the Deduplication Database.

    Skip this step for planned failover operations.

  6. Stop NetApp services on the production CommServe host.
  7. Enable scheduler operations on the standby CommServe host.
  8. When NetApp services are running on the standby CommServe host, resume any pending backup and restore jobs from the CommCell Console.

Result

The standby CommServe will now become the active node and performs all operations of the production CommServe host.

Note: After a failover operation, you will notice a considerable increase in the job ID for new jobs. This increase is added to avoid conflicts with job IDs referenced in the deduplication databases (DDBs) when the DDBs are resynchronized.

What To Do Next

After you move CommCell operations to the standby CommServe host, complete the following tasks:

  1. Rebuild your original production CommServe host and stage the CommServe database.
    1. Install the CommServe software on the original production host. Review CommServe Installation: Considerations for Disaster Recovery Failover.
    2. Install the SQL Server Agent on a new instance. Review SQL Server Agent Installation: Considerations for Disaster Recovery Failover.
    3. Install the CommServe Failover Component on the second instance.
    4. Configure a SQL Server Agent Subclient  for the second instance of the CommServe client.
    5. Configure the CommServe Failover Component using basic configuration type. Provide the original configuration values used for the production CommServe host.
    6. Stop Services on the original production CommServe host.
    7. Backup and restore the CommServe databases from the standby CommServe host to the original production CommServe host. See Synchronize the CommServe Databases.
    8. Create schedules to backup and restore the SQL logs to the original production CommServe host.
  2. Prepare the standby CommServe host for a fail back operation. Complete the following steps:
  3. Fail back the CommServe functionality to the original production CommServe host using the following steps:
    1. From the Start menu on the production CommServe host, right-click the Command Prompt and then click Run as administrator.
    2. At the command prompt on the production CommServe host, go to Installation_Directory_Of_Second_Instance /cvfailover, and type the following command:

      cvfailover /RunCriticalFailback

      • Enter your local SQL Server Authentication user account having sysadmin capabilities.
      • Enter the password for the local SQL Server Authentication user account.

        Refer note on using special characters in the password.

  4. Update the DNS records to change the IP address of the floating CommServe name.

    Delete the current floating CommServe entry and add a new entry with the IP address of the production CommServe host. See Deleting a DNS A Record and Creating a DNS A Record.

    Note: You can also create a prescript to update the DNS records and update the preStartScript parameter in the cvfailover.cfg configuration file.

  5. Stop NetApp services on the standby CommServe host.
  6. Enable scheduler operations on the production CommServe host.
  7. Download the latest software updates to the software cache directory on the standby CommServe host. For more information on downloading updates, see Getting Started - Download Updates.