mfschunkserver.cfg(5)

NAME

mfschunkserver.cfg - main configuration file for mfschunkserver

DESCRIPTION

The file mfschunkserver.cfg contains the configuration of the LizardFS chunkserver process.

SYNTAX

OPTION = VALUE

Lines starting with the # character are ignored.

OPTIONS

DATA_PATH
where to store files with usage statistics and daemon lock file
LABEL
the label of this chunkserver (for tiering)
WORKING_USER
user to run daemon as
WORKING_GROUP
group to run daemon as (optional - if empty then default user group will be used)
SYSLOG_IDENT
name of process to place in syslog messages (default is mfschunkserver)
LOCK_MEMORY
whether to perform mlockall() to avoid swapping out mfschunkserver process ( default is 0, i.e. no)
NICE_LEVEL
nice level to run daemon with (default is -19 if possible; note: process must be started as root to increase priority)
MASTER_HOST
address of LizardFS master host to connect with (default is mfsmaster)
MASTER_PORT
number of LizardFS master port to connect with (default is 9420)
MASTER_RECONNECTION_DELAY
delay in seconds before trying to reconnect to the master server after disconnection (default is 5)
MASTER_TIMEOUT
timeout (in seconds) for the master server connection (default is 60, minimum is 0.01)
BIND_HOST
local address to use for connecting with the master server (default is *, i.e. default local address)
CSSERV_LISTEN_HOST
IP address to listen on for client (mount) connections (* means any)
CSSERV_LISTEN_PORT
port to listen on for client (mount) connections (default is 9422)
CSSERV_TIMEOUT
timeout (in seconds) for client (mount) connections (default is 5)
HDD_CONF_FILENAME
alternative name of mfshdd.cfg file
HDD_LEAVE_SPACE_DEFAULT
free space threshold to set volume as 100% utilized when there is less than given amount of free space left (default is “4GiB”). This number is always added to the used disk space reported by chunkserver.
HDD_TEST_FREQ
chunk test period in seconds (default is 10)
HDD_ADVISE_NO_CACHE
whether to remove each chunk from page when closing it to reduce cache pressure generated by chunkserver (default is 0, i.e. no)
HDD_PUNCH_HOLES
if enabled then chunkserver detects zero values in chunk data and frees corresponding file blocks (decreasing file system usage). This option works only on Linux and only with file systems supporting punching holes (XFS, ext4, Btrfs, tmpfs)
REPLICATION_BANDWIDTH_LIMIT_KBPS
limit how many kilobytes can be replicated from other chunkservers to this chunkserver in every second (by default undefined, i.e. no limits)
NR_OF_NETWORK_WORKERS
number of threads which handle (in a round-robin manner) connections with clients (default is 1); these threads are responsible for reading from sockets and copying data from internal buffers to sockets
NR_OF_HDD_WORKERS_PER_NETWORK_WORKER
number of threads that each network worker may use to do disk operations like opening chunks, reading or writing them (default is 2)
READ_AHEAD_KB
additional number of kilobytes which should be passed to posix_fadvise(POSIX_FADV_WILLNEED) before reading data from a chunk (default is 0, i.e. use posix_fadvise only with the amount of data that is really needed; the value is aligned down to 64 KiB)
MAX_READ_BEHIND_KB
try to fix out-of-order read requests; the value tells how much of skipped data to read if an offset of some read operation is greater than the offset where the previos operation finished (default is 0, i.e. don’t read any skipped data; the value is aligned down to 64 KiB)
CREATE_NEW_CHUNKS_IN_MOOSEFS_FORMAT
whether to create new chunks in the MooseFS format (signature + <checksum> + <data block>) or in the newer interleaved format ([<checksum> <data block>]*). (Default is 1, i.e. new chunks are created in MooseFS format)
PERFORM_FSYNC
call fsync() after a chunk is modified (default is 1, i.e. enabled)

REPORTING BUGS

Report bugs to <contact@lizardfs.org>.

SEE ALSO

mfschunkserver(8), mfshdd.cfg(5)