Verifying HotStandby server states

High Availability Guide : Administering and configuring HotStandby : Administering HotStandby with ADMIN COMMANDs (HotStandby API) : Verifying HotStandby server states

You can check the state of HotStandby servers by using the ADMIN COMMAND 'hotstandby state' command.

Procedure

To check the current state of a HotStandby server, issue the following HotStandby command in the server:

ADMIN COMMAND 'hotstandby state';

Results

For descriptions of possible states the command returns, see Description of server states.

Note

1 If the server is configured as a HotStandby server, when the server is started, the server starts in the SECONDARY ALONE state.

2 The server cannot return the state OFFLINE because when the server is in the OFFLINE state, you cannot connect to it and issue any query (such as ADMIN COMMAND 'hotstandby state').

3 If ADMIN COMMAND 'hotstandby state' is issued on a server that is not configured as a HotStandby, the following error message is returned:

14527: This is a non-HotStandby Server

If HAC, and HA Manager are used, the HA Manager displays the HSB states of both servers. The information is queried periodically every second.

What to do next

For a summary of HotStandby state transitions that occur while performing administrative and troubleshooting operations, see Server state transitions.

Server state combinations

All combinations of server states are not possible. For example, if the Primary is in PRIMARY ACTIVE state, the Secondary can be only in SECONDARY ACTIVE state.

The following table shows possible server states of a HotStandby server when its associated server is in a particular state.

State of the server	Possible states of the associated server
PRIMARY ACTIVE	SECONDARY ACTIVE
PRIMARY ALONE	PRIMARY ALONE * PRIMARY UNCERTAIN SECONDARY ALONE STANDALONE *
PRIMARY UNCERTAIN	PRIMARY ALONE PRIMARY UNCERTAIN SECONDARY ALONE STANDALONE
SECONDARY ACTIVE	PRIMARY ACTIVE
SECONDARY ALONE	PRIMARY ALONE PRIMARY UNCERTAIN SECONDARY ALONE STANDALONE
STANDALONE	PRIMARY ALONE * PRIMARY UNCERTAIN SECONDARY ALONE STANDALONE *

* If one server is in the PRIMARY ALONE state or STANDALONE state, the other server cannot be in the PRIMARY ALONE or STANDALONE state. This is because if changes are made to both servers independently, there is no way to merge the two databases into one.