NAME

       drbd-wait-promotable@.service - Wait for DRBD to become promotable

SYNOPSIS

       drbd-wait-promotable@RESNAME.service - Wait for DRBD to become promotable

DESCRIPTION

       Usually you do not want to "hardcode" an unconditional promotion attempt of DRBD
       resources, because you usually cannot know a-priory whether this instance of DRBD will
       have access to good data (yet).

       If you try to promote (mount, use) DRBD before it can be certain to have access to good
       data, the attempt will fail in various ways, typically claiming "wrong medium type", "need
       access to good data".

       This unit will wait for the DRBD internal state to indicate that it has access to good
       data. It does not monitor the state further, so this is good enough only to avoid trying
       to mount "too early" if you hard-code the mount attempt into your boot sequence, for
       example using an fstab entry or similar.

       To monitor and react to DRBD state changes, use drbd-reactor or a cluster manager like
       pacemaker.

       If you systemctl enable this unit, it will be required by drbd@.target, so anything
       depending on that target, for example an fstab entry, will implicitly wait until this DRBD
       indicated it was "healthy enough" to be used.

       It can still timeout, in which case systemd sees this as a start failure, and starting of
       any dependencies (e.g. the mount) won’t be attempted at this point.

SEE ALSO

       drbd@.service(7), drbd@.target(7), drbd-lvchange@.service(7)

AUTHORS

       LINBIT HA Solutions GmbH https://linbit.com