1. Essentials Guide
  2. The Session Load Balancer and Route Manager
  3. SLRM Operation
  4. Re-balancing

Re-balancing

Re-balancing is the process of taking some number of registered users from a functioning Oracle Communications Core Session Managers and redistributing them between other Oracle Communications Core Session Managers. Re-balancing occurs when manually invoked by the user from the Oracle Communications Core Session Manager using the release-users command.

The Oracle Communications Core Session Manager initiates a Reg-Event process to de-register the users. This process includes the following steps:

  1. The Oracle Communications Core Session Manager waits for users to send registration refresh.
  2. Upon receipt of the users first registration refresh, the Oracle Communications Core Session Manager sends an Administrative_Deregistration SAR to the HSS.
  3. The Oracle Communications Core Session Manager sends a 504 Server Timeout to any ensuing registration refreshes by the endpoint.
  4. The HSS sets the PUID to Not Registered and clears its S-CSCF association.
  5. The HSS sends an SAA back to the Oracle Communications Core Session Manager.
  6. The Oracle Communications Core Session Manager de-registers the user.
  7. The Oracle Communications Core Session Manager sends a NOTIFY messages to all REGEVENT subscribers indicating the de-registration event has taken place.

Note that the Oracle Communications Core Session Manager can accept new registrations during the re-balance process. The process includes a time out at 30 minutes, after which the release-user command stops releasing users regardless of whether it has reached the configured user count. If the user issues the release-users command again, the Oracle Communications Core Session Manager re-starts the process. After completion, the Oracle Communications Core Session Manager echoes a message indicating the re-balance is complete.

Note:

If an HA switchover occurs before the release-users command has finished, the process does not continue to release users. If desired, the user can re-issue the command on the backup system after the switchover is complete.