For administration, the main command is drbdadm. There are a number of commands supported by this tool the control the connectivity and status of the DRBD devices.
For convenience, a bash completion script is available that
provides tab completion for options to
drbdadm. The file
drbdadm.bash_completion can be found
within the standard DRBD source package within the
scripts directory. To enable, copy the
file to /etc/bash_completion.d/drbdadm.
You can load it manually by using:
shell> source /etc/bash_completion.d/drbdadm
The most common commands are those to set the primary/secondary status of the local device. You can manually set this information for a number of reasons, including when you want to check the physical status of the secondary device (since you cannot mount a DRBD device in primary mode), or when you are temporarily moving the responsibility of keeping the data in check to a different machine (for example, during an upgrade or physical move of the normal primary node). You can set state of all local device to be the primary using this command:
root-shell> drbdadm primary all
Or switch the local device to be the secondary using:
root-shell> drbdadm secondary all
To change only a single DRBD resource, specify the resource name
instead of all.
You can temporarily disconnect the DRBD nodes:
root-shell> drbdadm disconnect all
Reconnect them using connect:
root-shell> drbdadm connect all
For other commands and help with drbdadm see the DRBD documentation.