Kernel Module Operations¶
Important
To use kernel module operations, you must have a running Ceph cluster.
Get a List of Images¶
To mount a block device image, first return a list of the images.
rbd list
Map a Block Device¶
Use rbd to map an image name to a kernel module. You must specify the
image name, the pool name, and the user name. rbd will load RBD kernel
module on your behalf if it’s not already loaded.
sudo rbd map {pool-name}/{image-name} --id {user-name}
For example:
sudo rbd map rbd/myimage --id admin
If you use cephx authentication, you must also specify a secret. It may come from a keyring or a file containing the secret.
sudo rbd map rbd/myimage --id admin --keyring /path/to/keyring
sudo rbd map rbd/myimage --id admin --keyfile /path/to/file
Show Mapped Block Devices¶
To show block device images mapped to kernel modules with the rbd command,
specify the showmapped option.
rbd showmapped
Unmapping a Block Device¶
To unmap a block device image with the rbd command, specify the unmap
option and the device name (i.e., by convention the same as the block device
image name).
sudo rbd unmap /dev/rbd/{poolname}/{imagename}
For example:
sudo rbd unmap /dev/rbd/rbd/foo
