Tip
The ceph fs new command was introduced in Ceph 0.84. Prior to this release, no manual steps are required to create a filesystem, and pools named data and metadata exist by default.
The Ceph command line now includes commands for creating and removing filesystems, but at present only one filesystem may exist at a time.
A Ceph filesystem requires at least two RADOS pools, one for data and one for metadata. When configuring these pools, you might consider:
Refer to Pools to learn more about managing pools. For example, to create two pools with default settings for use with a filesystem, you might run the following commands:
$ ceph osd pool create cephfs_data <pg_num>
$ ceph osd pool create cephfs_metadata <pg_num>
Once the pools are created, you may enable the filesystem using the fs new command:
$ ceph fs new <fs_name> <metadata> <data>
For example:
$ ceph fs new cephfs cephfs_metadata cephfs_data
$ ceph fs ls
name: cephfs, metadata pool: cephfs_metadata, data pools: [cephfs_data ]
Once a filesystem has been created, your MDS(s) will be able to enter an active state. For example, in a single MDS system:
$ ceph mds stat
e5: 1/1/1 up {0=a=up:active}
Once the filesystem is created and the MDS is active, you are ready to mount the filesystem: