Notice

This document is for a development version of Ceph.

Client Configuration

Updating Client Configuration

Certain client configurations can be applied at runtime. To check if a configuration option can be applied (taken into affect by a client) at runtime, use the config help command:

ceph config help debug_client
 debug_client - Debug level for client
 (str, advanced)                                                                                                                      Default: 0/5
 Can update at runtime: true

 The value takes the form 'N' or 'N/M' where N and M are values between 0 and 99.  N is the debug level to log (all values below this are included), and M is the level to gather and buffer in memory.  In the event of a crash, the most recent items <= M are dumped to the log file.

config help tells if a given configuration can be applied at runtime along with the defaults and a description of the configuration option.

To update a configuration option at runtime, use the config set command:

ceph config set client debug_client 20/20

Note that this changes a given configuration for all clients.

To check configured options use the config get command:

ceph config get client
 WHO    MASK LEVEL    OPTION                    VALUE     RO
 client      advanced debug_client              20/20
 global      advanced osd_pool_default_min_size 1
 global      advanced osd_pool_default_size     3

Client Config Reference

client_acl_type

Set the ACL type. Currently, only possible value is "posix_acl" to enable POSIX ACL, or an empty string. This option only takes effect when the fuse_default_permissions is set to false.

type

str

client_cache_mid

Set client cache midpoint. The midpoint splits the least recently used lists into a hot and warm list.

type

float

default

0.75

client_cache_size

Set the number of inodes that the client keeps in the metadata cache.

type

size

default

16Ki

client_caps_release_delay

Set the delay between capability releases in seconds. The delay sets how many seconds a client waits to release capabilities that it no longer needs in case the capabilities are needed for another user space operation.

type

int

default

5

client_debug_force_sync_read

If set to true, clients read data directly from OSDs instead of using a local page cache.

type

bool

default

false

client_dirsize_rbytes

This option enables a CephFS feature that stores the recursive directory size (the bytes used by files in the directory and its descendents) in the st_size field of the stat structure.

type

bool

default

true

client_max_inline_size

Set the maximum size of inlined data stored in a file inode rather than in a separate data object in RADOS. This setting only applies if the inline_data flag is set on the MDS map.

type

size

default

4Ki

client_metadata

Comma-delimited strings for client metadata sent to each MDS, in addition to the automatically generated version, host name, and other metadata.

type

str

client_mount_gid

Set the group ID of CephFS mount.

type

int

default

-1

client_mount_timeout

Set the timeout for CephFS mount in seconds.

type

float

default

5 minutes

client_mount_uid

Set the user ID of CephFS mount.

type

int

default

-1

client_mountpoint

Directory to mount on the CephFS file system. An alternative to the -r option of the ceph-fuse command.

type

str

default

/

client_oc

enable object caching

type

bool

default

true

client_oc_max_dirty

Set the maximum number of dirty bytes in the object cache.

type

size

default

100Mi

client_oc_max_dirty_age

Set the maximum age in seconds of dirty data in the object cache before writeback.

type

float

default

5.0

client_oc_max_objects

Set the maximum number of objects in the object cache.

type

int

default

1000

client_oc_size

Set how many bytes of data will the client cache.

type

size

default

200Mi

client_oc_target_dirty

Set the target size of dirty data. We recommend to keep this number low.

type

size

default

8Mi

client_permissions

Check client permissions on all I/O operations.

type

bool

default

true

client_quota_df

Report root directory quota for the statfs operation.

type

bool

default

true

client_readahead_max_bytes

Set the maximum number of bytes that the client reads ahead for future read operations. Overridden by the client_readahead_max_periods setting.

type

size

default

0B

client_readahead_max_periods

Set the number of file layout periods (object size * number of stripes) that the client reads ahead. Overrides the client_readahead_max_bytes setting.

type

int

default

4

client_readahead_min

Set the minimum number bytes that the client reads ahead.

type

size

default

128Ki

client_reconnect_stale

reconnect when the session becomes stale

type

bool

default

false

client_snapdir

Set the snapshot directory name.

type

str

default

.snap

client_tick_interval

Set the interval in seconds between capability renewal and other upkeep.

type

secs

default

1

client_use_random_mds

Choose random MDS for each request.

type

bool

default

false

fuse_default_permissions

When set to false, ceph-fuse utility checks does its own permissions checking, instead of relying on the permissions enforcement in FUSE. Set to false together with the client acl type=posix_acl option to enable POSIX ACL.

type

bool

default

false

fuse_max_write

Set the maximum number of bytes in a single write operation. A value of 0 indicates no change; the FUSE default of 128 kbytes remains in force.

type

size

default

0B

fuse_disable_pagecache

If set to true, kernel page cache is disabled for ceph-fuse mounts. When multiple clients read/write to a file at the same time, readers may get stale data from page cache. Due to limitations of FUSE, ceph-fuse can’t disable page cache dynamically.

type

bool

default

false

Developer Options

Important

These options are internal. They are listed here only to complete the list of options.

client_debug_getattr_caps
type

bool

default

false

client_debug_inject_tick_delay
type

secs

default

0

client_inject_fixed_oldest_tid
type

bool

default

false

client_inject_release_failure
type

bool

default

false

client_trace

file containing trace of client operations

type

str