mount.ceph – mount a ceph file system¶
Synopsis¶
Description¶
mount.ceph is a simple helper for mounting the Ceph file system on a Linux host. It serves to resolve monitor hostname(s) into IP addresses and read authentication keys from disk; the Linux kernel client component does most of the real work. In fact, it is possible to mount a non-authenticated Ceph file system without mount.ceph by specifying monitor address(es) by IP:
mount -t ceph 1.2.3.4:/ mountpoint
Each monitor address monaddr takes the form host[:port]. If the port is not specified, the Ceph default of 6789 is assumed.
Multiple monitor addresses can be separated by commas. Only one responsible monitor is needed to successfully mount; the client will learn about all monitors from any responsive monitor. However, it is a good idea to specify more than one in case one happens to be down at the time of mount.
A subdirectory subdir may be specified if a subset of the file system is to be mounted.
Mount helper application conventions dictate that the first two options are device to be mounted and destination path. Options must be passed only after these fixed arguments.
Options¶
- wsize
int (bytes), max write size. Default: none (writeback uses smaller of wsize and stripe unit)
- rsize
int (bytes), max read size. Default: none
- rasize
int (bytes), max readahead, multiple of 1024, Default: 8388608 (8192*1024)
- osdtimeout
int (seconds), Default: 60
- osdkeepalivetimeout
int, Default: 5
- mount_timeout
int (seconds), Default: 60
- osd_idle_ttl
int (seconds), Default: 60
- caps_wanted_delay_min
int, cap release delay, Default: 5
- caps_wanted_delay_max
int, cap release delay, Default: 60
- cap_release_safety
int, Default: calculated
- readdir_max_entries
int, Default: 1024
- readdir_max_bytes
int, Default: 524288 (512*1024)
- write_congestion_kb
int (kb), max writeback in flight. scale with available memory. Default: calculated from available memory
- snapdirname
string, set the name of the hidden snapdir. Default: .snap
- name
RADOS user to authenticate as when using cephx. Default: guest
- secret
secret key for use with cephx. This option is insecure because it exposes the secret on the command line. To avoid this, use the secretfile option.
- secretfile
path to file containing the secret key to use with cephx
- ip
my ip
- noshare
create a new client instance, instead of sharing an existing instance of a client mounting the same cluster
- dirstat
funky cat dirname for stats, Default: off
- nodirstat
no funky cat dirname for stats
- rbytes
Report the recursive size of the directory contents for st_size on directories. Default: on
- norbytes
Do not report the recursive size of the directory contents for st_size on directories.
- nocrc
no data crc on writes
- noasyncreaddir
no dcache readdir
Examples¶
Mount the full file system:
mount.ceph monhost:/ /mnt/foo
If there are multiple monitors:
mount.ceph monhost1,monhost2,monhost3:/ /mnt/foo
If ceph-mon(8) is running on a non-standard port:
mount.ceph monhost1:7000,monhost2:7000,monhost3:7000:/ /mnt/foo
To mount only part of the namespace:
mount.ceph monhost1:/some/small/thing /mnt/thing
Assuming mount.ceph(8) is installed properly, it should be automatically invoked by mount(8) like so:
mount -t ceph monhost:/ /mnt/foo
Availability¶
mount.ceph is part of Ceph, a massively scalable, open-source, distributed storage system. Please refer to the Ceph documentation at http://ceph.com/docs for more information.
