CephFS Standalone Mount Tool

CephFS is part of the Linux kernel, so you don't need the userland Ceph packages installed.

Usually, /sbin/mount.ceph is shipped by the Ceph packages written in C++. This standalone pure Python implementation mimics the mount.ceph functionality.

With this script you can mount Ceph e.g. with systemd mount units without installing Ceph.

This tool can upload the secret key into the kernel keyring and mount your CephFS.

mount.ceph is the "high-level" mount helper, cephfs_mount is the "low-level" tool which actually mounts.

Installation

mount -t ceph really only calls /sbin/mount.ceph, so we need to provide that file.

Way 1:

• Clone the repo e.g. to /opt/ceph-mount via git clone https://github.com/SFTtech/ceph-mount /opt/ceph-mount
• Symlink /sbin/mount.ceph -> /opt/ceph-mount/mount.ceph

Way 2:

• Install mount.ceph and cephfs_mount to /usr/bin/
• Symlink /sbin/mount.ceph -> /usr/bin/mount.ceph

Way 3:

• Install mount.ceph and cephfs_mount to /sbin/

Examples

/sbin/mount.ceph is called by mount when the fstype is ceph, so that's how an entry in /etc/fstab still makes use of this tool.

Likely mount.ceph --help or cephfs_mount --help will guide you.

Example /etc/fstab entry:

mon1.ceph.lol,mon2.ceph.lol,mon3.ceph.lol:/your/path /your/mountpoint ceph rw,noatime,name=your-auth-name,secretfile=/etc/ceph/ceph.client.your-auth-name.keyring,_netdev 0 0

Example mount invocation:

mount -t ceph -o rw,noatime,name=your-auth-name,secretfile=/etc/ceph/ceph.client.your-auth-name.keyring mon1.ceph.lol,mon2.ceph.lol,mon3.ceph.lol:/your/path /your/mountpoint

Example ./cephfs_mount invocation:

./cephfs_mount --user your-auth-name mon1.ceph.lol,mon2.ceph.lo,mon3.ceph.lol:/path /destination
# this looks in /etc/ceph/ceph.client.your-auth-name.keyring for the key
# if you write :/path only, it uses the MONs from /etc/ceph/ceph.conf

If in doubt, look at the source code :)

Complete example

A complete example for manual mounting by setting up the monitors in a ceph.conf and the secret key as a file.

ceph path	mount path	ceph name	key	monitor domain names
/nilm	/home/ubuntu/nilm	fs.nilm	my-secret-key-ABCDEFG	monitor1.domain.com,monitor2.domain.com

Watch to put a space before the echo commands to not add the secrets to your terminal history.

/home/ubuntu> sudo git clone https://github.com/SFTtech/ceph-mount /opt/ceph-mount
/home/ubuntu> sudo ln -s /opt/ceph-mount/mount.ceph /sbin/mount.ceph
/home/ubuntu> sudo mkdir /etc/ceph
/home/ubuntu>  sudo echo "my-secret-key-ABCDEFG" > /etc/ceph/nilm.keyring
/home/ubuntu>  sudo echo -e "[global]\nmon_host=monitor1.domain.com,monitor2.domain.com" > /etc/ceph/ceph.conf
/home/ubuntu> mkdir /home/ubuntu/nilm
/home/ubuntu> sudo mount -t ceph :/nilm /home/ubuntu/nilm -o name=fs.nilm,secretfile=/etc/ceph/nilm.keyring

Contact

If you have questions, suggestions, encounter any problem, please join our Matrix or IRC channel and ask!

#sfttech:matrix.org
irc.freenode.net #sfttech

License

License: GPL version 3 (or any later version)