Change the database server mode

If you change the mode of a database server in a high-availability cluster, replication stops.

To change the database server mode, use the onmode utility.

The following table summarizes the effects of changing the mode of the primary database server.

Table 1. Mode changes on the primary database server
On the primary On the secondary To restart HDR
From any mode to offline:

(onmode -k)

Secondary displays: DR: Receive error.

HDR is turned off.

The mode remains read-only.

If DRAUTO is set to 0, the mode remains read-only.

If DRAUTO is set to 1, the secondary server switches to standard type and can accept updates. (If DRAUTO is set to 2 , the secondary database server becomes a primary database server as soon as the connection ends when the old primary server fails.)

Treat it like a failure of the primary. Two different scenarios are possible, depending on what you do with the secondary database server while the primary database server is offline. See these sections for information:
  • The secondary server was not changed to the primary server
  • The secondary server was changed to the primary server automatically

See Restart if the primary server fails.

To online, quiescent, or administration mode:

(onmode -s / onmode -u)

(onmode -j )

Secondary does not receive errors.

HDR remains on.

Mode remains read-only.

Use onmode -m on the primary.

The following table summarizes the effects of changing the mode of the secondary database server.

Table 2. Mode changes on the secondary database server
On the secondary On the primary To restart HDR
Read-only offline

(onmode -k)

Primary displays: DR: Receive error.

HDR is turned off.

Treat it as you would a failure of the secondary. Follow the procedures in Restarting HDR or RS clusters if the secondary server fails.
Quiescent

(onmode -s)

Primary does not receive errors.

HDR remains on.

Use onmode -m on the secondary.

Administration mode operates the same way on an HDR secondary database server as it does on the primary database server.


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