Command line options

From Ceph wiki

MDS

Default options:

Example:

cmds -i 0 -c /etc/ceph/ceph.conf

-i

instance number (relates to the MDS number in the config file)

-c or --conf

config file path (will not default to /etc/ceph)

Debug options:

-D

Debug mode: do not daemonize after startup (run in foreground) and send log output to stdout.

-f

do not daemonize after startup (run in foreground), but log to the usual location. Useful when run via cron(8).

Less common / special options

--mds rank

Start up as (or standby for) the given MDS rank. If not specified, a rank will be assigned by the monitor cluster.

--shadowrank

Shadow the given MDS rank. The given MDS log will be replayed, checking for recovery errors.

--mds_cache_size <num>

Sets the amount of CInodes the MDS caches.

-m monaddress[:port]

Connect to specified monitor (instead of looking through ceph.conf), i.e. for cfuse

Some options from config.cc that can also go to cmdline:

--mds_reconnect_timeout

seconds to wait for clients during mds restart

--mds_use_tmap

use trivialmap for dir updates

FUSE Client

Example:

mkdir /mnt/ceph
cfuse -m monitorIP:6789 /mnt/ceph

Note: in order to mount as a regular user, the user must have writing permissions on /mnt/ceph.

Debug options:

--debug_ms <num>

Values for <num> are as in ceph.conf for servers

--debug_client <num>

Values for <num> are as in ceph.conf for servers

--log-file=<file>

Output log file

Librados

-c or --conf

config file path (will default to /etc/ceph/ceph.conf)

-m

Monitor's IP Address

-K

Cephx keyring file

-k

Cephx keyfile (base64 encoded string)

-n

Cephx auth name (To be used in conjunction with -k)