Adds in three parts:
1. Create an API endpoint to create OSD DB volume groups on a device.
Passed through to the node via the same command pipeline as
creating/removing OSDs, and creates a volume group with a fixed name
(osd-db).
2. Adds API support for specifying whether or not to use this DB volume
group when creating a new OSD via the "ext_db" flag. Naming and sizing
is fixed for simplicity and based on Ceph recommendations (5% of OSD
size). The Zookeeper schema tracks the block device to use during
removal.
3. Adds CLI support for the new and modified API endpoints, as well as
displaying the block device and DB block device in the OSD list.
While I debated supporting adding a DB device to an existing OSD, in
practice this ended up being a very complex operation involving stopping
the OSD and setting some options, so this is not supported; this can be
specified during OSD creation only.
Closes#142
This should be managed in ceph.conf with the `rbd default
features` configuration option instead, and thus can be tailored to the
underlying OS version.
If this isn't, the resize will be interpreted as a MB value and result
in an absurdly big volume instead. This is the same consistency
validation that occurs on add.
Convert from human to bytes, then to megabytes and always pass this to
the RBD command. This ensures consistency regardless of what is actually
passed by the user.
Ensures that the bytes_tohuman returns an integer to avoid the hacky
workaround of stripping off the B.
Adds a verification on the size of a new volume, that it is not larger
than the free space of the pool to prevent errors/excessively-large
volumes from being created.
Closes#120
This wasn't happening automatically, nor does it happen with qemu-img
commands, so we have to manually trigger a libvirt blockResize against
the volume. This setup is a little roundabout but seems to work fine.
Joshua Boniface