Question & Answer
What order should the TEMS upgrade proceed when hotstandby is operational?
When a hot standby or FTO hub TEMS mirror is operating, any update to the other hub TEMS may result in an unexpected re-action from the mirroring hub. In some cases this has resulted in lost data and a length recovery. Here is a best practice upgrade procedure which avoids that issue.
In the following steps the hub TEMS/primary is the current operational hub TEMS that events are flowing through. The mirror is called the hub TEMS/backup. Of course these roles are temporary and can switch at any time, but for these purposes it is useful to have fixed names.
1) Stop the hub TEMS/primary and configure that hub TEMS without FTO.
2) The hub TEMS/backup takes on all the work and cannot find its partner,
3) The remote TEMSes switch over to the new hub,
4) Perform update on the hub TEMS,
5) Stop the hub TEMS/backup.
6) Reconfigure the hub TEMS/primary with FTO and start it.
7) Reconfigure the hub TEMS/backup without FTO.
8) Perform update on hub TEMS/backup.
9) Reconfigure hub TEMS/backup with FTO
10) Start up hub TEMS/backup
11) Stop each remote TEMS, upgrade, and restart
This sequence will preserve the integrity of the hub TEMS database tables.
If you have a single TEPS, than it can be upgraded next.
Some installations have duplicate Portal Servers, one for the hub TEMS/primary and one for the hub TEMS/backup. In that case update the TEPSes as follows:
1) Stop the TEPS/primary
2) Upgrade the TEPS/primary and also do a migrate-export of the data
3) Start the TEPS primary
4) Stop the TEPS/backup at this step
5) Upgrade the TEPS/backup migrate-import to make the two TEPS databases identical.
6) Start the TEPS/backup
The migrate-export/migrate-import should be performed regularly to keep the two TEPS database tables in sync.
17 June 2018