How to replace Passive Servers

Posted on 4:27 PM by Bharathvn

How to Resolve two passive servers


Symptoms

If you have two passive servers, users are unable to connect to protected applications. This issue must be resolved immediately.

If alerts are configured, you receive notification that replication is not functioning properly.

This is the result of:

  • A sudden failure of the active server (for example, unexpected termination of the Neverfail Server R2 service, a transient power failure, a server reset triggered from the 'Power' or 'Reset' button, or any other unclean shutdown). Following an unclean shutdown, an active server automatically assumes the passive role to isolate itself from the network until the failure can be investigated.
  • A failure of the active server before completion of the handshake that establishes the VMware Channel. The passive server cannot detect that the active server is not responding when the failure occurs - no channel connection was established. The active server may suffer a transient failure and the passive server cannot respond by failing over into the active role leaving both servers in the passive role.
  • Both Primary and Secondary server experience a power outage simultaneously (for example, because they are using the same power source and neither is attached to a UPS). A failover is not be possible. When the servers are rebooted, each displays the error message:

    Cannot start replication because previous run did not shutdown properly. Check configuration

If you attempt to start vCenter Server Heartbeat without reconfiguring one server in the pair as active, Heartbeat responds with the warning:

[U16] Serious configuration mismatch between the two servers. Please reconfigure so there is one and only one Primary, and one and only one Active.

Purpose

This article provides steps to resolve a situation where two passive servers exist.

Resolution

To resolve two passive servers:
  1. Determine which server should be active.
  2. If vCenter Server Heartbeat is running on either server, shut it down. Leave any protected applications running on the server you want to make active.
  3. On the server you want to make active, open the Configure Server wizard.
  4. Click the Machine tab, select the active role, and click Finished. Do NOT change the Identity.
  5. Save the changes and exit the wizard.
  6. On the server you want to make passive, open the Configure Server wizard, and confirm that the role is passive. Do NOT change the Identity.
  7. Exit the wizard.
  8. Reboot both servers to ensure that all protected application services are stopped on the passive server and started on the active server.
  9. Start vCenter Server Heartbeat on both servers.