New upstream version 8.1.0

2025-08-10 01:34:16 +02:00
commit c891bb7105
4398 changed files with 838833 additions and 0 deletions
--- a/client_module/build/dist/etc/beegfs-client.conf
+++ b/client_module/build/dist/etc/beegfs-client.conf
@@ -0,0 +1,755 @@
+# This is a config file for BeeGFS clients.
+# http://www.beegfs.com
+
+
+# --- [Table of Contents] ---
+#
+# 1) Settings
+# 2) Mount Options
+# 3) Basic Settings Documentation
+# 4) Advanced Settings Documentation
+
+
+#
+# --- Section 1.1: [Basic Settings] ---
+#
+
+sysMgmtdHost                  =
+
+
+#
+# --- Section 1.2: [Advanced Settings] ---
+#
+
+connAuthFile                  = /etc/beegfs/conn.auth
+connDisableAuthentication     = false
+connClientPort                = 8004
+connMgmtdPort                 = 8008
+connPortShift                 = 0
+
+connCommRetrySecs             = 600
+connFallbackExpirationSecs    = 900
+connInterfacesFile            =
+connRDMAInterfacesFile        =
+connMaxInternodeNum           = 12
+connMaxConcurrentAttempts     = 0
+connNetFilterFile             =
+
+connUseRDMA                   = true
+connTCPFallbackEnabled        = true
+connTCPRcvBufSize             = 0
+connUDPRcvBufSize             = 0
+connRDMABufNum                = 70
+connRDMABufSize               = 8192
+connRDMAFragmentSize          = page
+connRDMATypeOfService         = 0
+connTcpOnlyFilterFile         =
+
+logClientID                   = false
+logLevel                      = 3
+
+quotaEnabled                  = false
+
+sysCacheInvalidationVersion   = true
+sysCreateHardlinksAsSymlinks  = false
+sysMountSanityCheckMS         = 11000
+sysSessionCheckOnClose        = false
+sysSyncOnClose                = false
+sysTargetOfflineTimeoutSecs   = 900
+sysUpdateTargetStatesSecs     = 30
+sysXAttrsEnabled              = false
+
+tuneFileCacheType             = buffered
+tunePreferredMetaFile         =
+tunePreferredStorageFile      =
+tuneRemoteFSync               = true
+tuneUseGlobalAppendLocks      = false
+tuneUseGlobalFileLocks        = false
+
+
+#
+# --- Section 1.3: [Enterprise Features] ---
+#
+# See end-user license agreement for definition and usage limitations of
+# enterprise features.
+#
+
+sysACLsEnabled                = false
+
+
+#
+# --- Section 2: [Mount Options] ---
+#
+
+# Valid mount options are:
+# cfgFile, logLevel, connPortShift, connMgmtdPort,
+# sysMgmtdHost, sysMountSanityCheckMS, connInterfacesList.
+#
+# Use the mount option "cfgFile" to specify a different config file
+# for the beegfs client.
+# Example:
+# $ /bin/mount -t beegfs beegfs_nodev /beegfs -ocfgFile=/etc/anotherconfig.conf
+#
+# Use the mount option "connInterfacesList" to pass the list of interfaces names.
+# These interfaces names should be space-separated.
+# Example:
+# $ /bin/mount -t beegfs beegfs_nodev /beegfs \
+#    -ocfgFile=/etc/anotherconfig.conf,connInterfacesList='ib0 eth0'
+#
+# Mount options override the corresponding config file values.
+# Example:
+# $ /bin/mount -ocfgFile=/etc/anotherconfig.conf,logLevel=3 ...
+
+
+#
+# --- Section 3: [Basic Settings Documentation] ---
+#
+
+# [sysMgmtdHost]
+# Hostname (or IP) of the host running the management service.
+# (See also "connMgmtdPort".)
+# Default: <none>
+
+
+#
+# --- Section 4: [Advanced Settings Documentation] ---
+#
+
+#
+# --- Section 4.1: [Connections & Communication] ---
+#
+
+# [connAuthFile]
+# The path to a file that contains a shared secret for connection based
+# authentication. Only peers that use the same shared secret will be able to
+# connect.
+# Default: <none>
+
+# [connDisableAuthentication]
+# If set to true, explicitly disables connection authentication and allow the
+# service to run without a connAuthFile. Running BeeGFS without connection
+# authentication is considered insecure and is not recommended.
+# Default: false
+
+# [connClientPort]
+# The UDP port of the client.
+# Default: 8004
+
+# [connMgmtdPort]
+# The UDP and TCP port of the management node.
+# Default: 8008
+
+# [connPortShift]
+# Shifts all following UDP and TCP ports according to the specified value.
+# Intended to make port configuration easier in case you do not want to
+# configure each port individually.
+# Default: 0
+
+# [connCommRetrySecs]
+# The time (in seconds) for retries in case a network communication fails
+# (e.g. if a server is down). After this time, the I/O operation will fail
+# and the calling process will receive an error.
+# Note: Set this value to 0 for infinite retries. In this case, a process
+#    accessing the file system will block until the corresponding server
+#    becomes available (or until it is interrupted by a signal).
+# Default: 600
+
+# [connFallbackExpirationSecs]
+# The time in seconds after which a connection to a fallback interface expires.
+# When a fallback connection expires, the system will try to establish a new
+# connection to the other hosts  primary interface (falling back to another
+# interface again if necessary).
+# Note: The priority of node interfaces can be configured using the
+#    "connInterfacesFile" parameter.
+# Default: 900
+
+# [connInterfacesFile]
+# The path to a text file that specifies the names of the interfaces, which
+# may be used for communication by other nodes. One interface per line. The
+# line number also defines the priority of an interface.
+# Example: "ib0" in the first line, "eth0" in the second line.
+# Values: This setting is optional. If unspecified, all available interfaces
+#    will be published and priorities will be assigned automatically.
+# Note: This has no influence on outgoing connections. The information is sent
+#    to other hosts to inform them about possible communication paths.
+# Default: <none>
+
+# [connInterfacesList]
+# Comma-separated list of interface names. Performs the same function as
+# connInterfacesFile.
+# If use as the mount option "connInterfacesList" to pass the list of interfaces
+# names then it override the corresponding config file/list values..
+# The interfaces names should be space-separated.
+# Example:
+# $ /bin/mount -t beegfs beegfs_nodev /beegfs \
+#    -ocfgFile=/etc/anotherconfig.conf,connInterfacesList='ib0 eth0'
+#
+# Default: <none>
+
+# [connRDMAInterfacesFile]
+# The path to a text file that specifies the names of IPoIB interfaces, which
+# may be used for outbound RDMA communication with other nodes. One interface
+# per line. These interfaces must be RDMA-capable NICs.
+#
+# All storage and metadata servers must be IP-reachable from each specified
+# interface.
+#
+# Specifying interfaces in this file limits which RDMA NICs are used for outbound
+# RDMA. Specifying multiple interfaces allows the client to use multiple RDMA
+# interfaces for outbound communication.
+#
+# Example: "ib0" in the first line, "ib1" in the second line.
+# Values: This setting is optional. When none are specified, the client will use
+#    the first client host interface that can reach the remote node via IPoIB,
+#    as decided by rdma_cm. When multiple interfaces are specified, the client
+#    round-robins creation of outbound RDMA connections across the specified
+#    interfaces.
+# Default: <none>
+
+# [connMaxInternodeNum]
+# The maximum number of simultaneous connections to the same node.
+# Default: 12
+
+# [connMaxConcurrentAttempts]
+# The maximum number of simultaneous connection attempts. This may help in case
+# establishing new connections keeps failing and produces fallbacks.
+# It may happen particularly when using RDMA in an Omni-Path setup. If you
+# don't have failing connection attempts, tuning this option might still lead
+# to a faster connection process. This option is experimental, so there is no
+# experience with different values. Setting it to 0 disables it, which means
+# concurrent connection attempts are not limited.
+# Default: 0
+
+# [connNetFilterFile]
+# The path to a text file that specifies allowed IP subnets, which may be used
+# for outgoing communication. One subnet per line in classless notation (IP
+# address and number of significant bits).
+# Example: "192.168.10.0/24" in the first line, "192.168.20.0/24" in the second
+# line.
+# This value is optional. If unspecified, all addresses are allowed for
+# outgoing communication.
+# Default: <none>
+
+# [connUseRDMA]
+# Enables the use of Remote Direct Memory Access (RDMA) for InfiniBand or RoCE.
+# For this setting to be effective, OFED ibverbs support also has to be enabled
+# at compile time of the beegfs client modules (typically via
+# beegfs-client-autobuild.conf).
+# Default: true
+
+# [connTCPFallbackEnabled]
+# Enables fallback from RDMA to TCP sockets when there is a problem connecting
+# via RDMA to a storage or meta node.
+# Default: true
+
+# [connTCPRcvBufSize], [connUDPRcvBufSize]
+# Sets the size for TCP and UDP socket receive buffers (SO_RCVBUF). The maximum
+# allowed value is determined by sysctl net.core.rmem_max. This value is ignored
+# if it is less than the default value determined by net.core.rmem_default.
+# For legacy reasons, the default value 0 indicates that the buffer size is set
+# to connRDMABufNum * connRDMABufSize.
+# -1 indicates that the buffer size should be left at the system default.
+# Default: 0
+
+# [connRDMABufNum], [connRDMABufSize], [connRDMAFragmentSize]
+# InfiniBand RDMA buffer settings.
+# connRDMABufSize is the maximum size of a buffer (in bytes) that will be sent
+# over the network; connRDMABufNum is the number of available buffers that can
+# be in flight for a single connection. These client settings are also applied
+# on the server side for each connection. Ideally, the largest, commonly used
+# filesytem chunksize should be < connRDMABufNum * connRDMABufSize to achieve
+# the best performance.
+#
+# The minimum usable value for connRDMABufNum is 3, which is required by the
+# BeeGFS RDMA protocol. Lower values will immediately result in communication
+# failures.
+#
+# connRDMAFragmentSize determines how contiguous memory is allocated per
+# buffer. If connRDMAFragmentSize=4096 and connRDMABufSize=8192, each buffer
+# is allocated in 2 regions of 4096 contiguous bytes. Less fragmentation
+# improves performance. The value "none" indicates that buffers will not be
+# fragmented, resulting in allocation of contiguous regions of
+# connRDMABufSize. The value "page" uses the Linux PAGE_SIZE as the
+# fragmentation value.
+# The reason for using fragmentation is that large allocations
+# are more likely to fail if there is a shortage of heap memory. The minimum
+# fragmentation value is PAGE_SIZE. Using larger values (or 0) should improve
+# performance and allows for larger values of connRDMABufSize.
+#
+# Note: RAM usage per connection is connRDMABufSize x connRDMABufNum x 2. Keep
+#    resulting RAM usage (x connMaxInternodeNum x number_of_clients) on the
+#    server in mind when increasing these values.
+# Default: 70, 8192, page
+
+# [connRDMAMetaBufNum], [connRDMAMetaBufSize], [connRDMAMetaFragmentSize]
+# InfiniBand RDMA buffer settings for connections to beegfs-meta.
+# These settings behave in the same way as connRDMABufNum, connRDMABufSize
+# and connRDMAFragmentize except that they are used for connections to
+# beegfs-meta.
+# Metadata messages are usuallly small and do not require the large amount
+# of buffer space that is typically configured for connections to
+# beegfs-storage. One exception to this would be if large extended attributes
+# are added to files.
+# connRDMAMetaBufNum = "default" indicates that connRDMABufNum should be used.
+# connRDMAMetaBufSize = "default" indicates that connRDMABufSize should be used.
+# connRDMAMetaFragmentSize = "default" indicates that connRDMAFragmentSize
+# should be used.
+# The minimum value for connRDMAMetaBufNum is 3.
+# Default: default, default, default
+
+# [connRDMATypeOfService]
+# InfiniBand provides the option to set a type of service for an application.
+# This type of service can be used by your subnet manager to provide Quality of
+# Service functionality (e.g. setting different service levels).
+# In openSM the service type will be mapped to the parameter qos-class, which
+# can be handled in your QoS configuration.
+# See
+#    www.openfabrics.org/downloads/OFED/ofed-1.4/OFED-1.4-docs/
+#    QoS_management_in_OpenSM.txt
+# for more information on how to configure openSM for QoS.
+# This parameter sets the type of service for all outgoing connections of this
+# daemon.
+# Default: 0 (Max: 255)
+
+# [connRDMAKeyType]
+# In RDMA, an "rkey" is used to provide an access token for a peer to access
+# local memory regions that are registered for RDMA. Historically,
+# BeeGFS used either a "DMA key" or an "unsafe global rkey" depending upon
+# whether or not "unsafe global rkey" is supported by the operating system.
+# This is now selectable. "DMA key" is not supported on kernel >= 4.9
+# unless MOFED is installed. If an unsupported option is specified, there
+# will be warnings in syslog and RDMA connections will not be established.
+# Use of "unsafe global rkey" is preferred, but generates a syslog message
+# every time an RDMA connection is established: "enabling unsafe global rkey".
+# Neither option is considered "safe" because they both provide access
+# to all DMA mapped memory for a given connection. This technique is
+# used to provide better performance for small I/O requests.
+# "register" uses a memory registration per connection to provide an rkey.
+# "register" is not compatible with NVIDIA GPUDirect Storage.
+# Specify "dma" or "register" to squelch the syslog warning.
+# Values: "global" (unsafe global rkey), "dma" (DMA key), "register"
+# (memory registration)
+# Default: "global"
+
+# [connTcpOnlyFilterFile]
+# The path to a text file that specifies IP address ranges to which no RDMA
+# connection should be established. This is useful e.g. for environments where
+# all hosts support RDMA, but some hosts cannot connect via RDMA to some other
+# hosts.
+# Example: "192.168.10.0/24" in the first line, "192.168.20.0/24" in the second
+#    line.
+# Values: This setting is optional.
+# Default: <none>
+
+# [connMessagingTimeouts]
+# These constants are used to set some of the connection timeouts for sending
+# and receiving data between services in the cluster. They used to be hard-coded
+# (CONN_LONG_TIMEOUT, CONN_MEDIUM_TIMEOUT and CONN_SHORT_TIMEOUT) but are now
+# made configurable for experimentation purposes.
+# This option takes three integer values of milliseconds, separated by a comma
+# in the order long, medium, short.
+# WARNING: This is an EXPERIMENTAL configuration option that should not be
+#     changed in production environments unless properly tested and validated.
+#     Some configurations can lead to service lockups and other subtle issues.
+#     Please make sure that you know exactly what you are doing and properly
+#     test any changes you make.
+# Default: 600000,90000,30000
+
+# [connRDMATimeouts]
+# These constants are used to set some of the timeouts for sending and receiving
+# data between services in the cluster via RDMA. They used to be
+# hard-coded IBVSOCKET_CONN_TIMEOUT_MS, IBVSOCKET_COMPLETION_TIMEOUT_MS,
+# IBVSOCKET_FLOWCONTROL_ONSEND_TIMEOUT_MS,
+# IBVSOCKET_FLOWCONTROL_ONRECV_TIMEOUT_MS and a 10000 literal for poll timeout
+# but are now made configurable for experimentation purposes.
+# This option takes five integer values of milliseconds, separated by a comma
+# in the order connectMS, completionMS, flowSendMS, flowRecvMS and pollMS.
+# WARNING: This is an EXPERIMENTAL configuration option that should not be
+#     changed in production environments unless properly tested and validated.
+#     Some configurations can lead to service lockups and other subtle issues.
+#     Please make sure that you know exactly what you are doing and properly
+#     test any changes you make.
+# Default: 5000,300000,180000,180000,10000
+
+
+# --- Section 4.2: [Logging] ---
+#
+
+# [logClientID]
+# Defines whether the ClientID should appear in each log line.
+# This is mainly helpful if BeeGFS is mounted multiple times on this machine.
+# Default: false
+
+# [logLevel]
+# Defines the amount of log messages. The higher this level, the more detailed
+# the log messages will be.
+# Level 3 will print connection messages, level 4 will print syscall messages,
+# level 5 will print debug messages.
+# Note: Levels above 3 might decrease performance.
+# Default: 3 (Max: 5)
+
+#
+# --- Section 4.3: [Quota Settings] ---
+#
+
+# [quotaEnabled]
+# Enables user and group quota support by transferring extra user data to the
+# servers. This uses quota information of the underlying file systems on the
+# storage servers, which needs to be enabled by the server administrator.
+# Note: In the first implementation, only quota monitoring is available.
+# Note: Get quota information with "beegfs-ctl --getquota".
+# Note: If this option is true, performance might be slightly decreased due to
+#    extra information tracking.
+# Default: false
+
+
+#
+# --- Section 4.4: [System Settings] ---
+#
+
+# [sysCacheInvalidationVersion]
+#
+# Enable the client to invalidate its cache and reload the inode of a file when
+# the version parameter of the file on metadata changes due to internal metadata
+# operations such as stripe pattern change. This is done by comparing the
+# version parameters on client and metadata on the first lookup after internal
+# metadata changes. If the versions differ, the client invalidates the cache and
+# reloads the inode.
+# Note: If this option is set to true, performance may be decreased.
+# Default: true
+
+# [sysCreateHardlinksAsSymlinks]
+# Create a symlink when an application tries to create a hardlink for files in
+# different directories.
+# Default: false
+
+# [sysMountSanityCheckMS]
+# Perform some basic checks during mount (e.g. whether the client helper daemon
+# and storage servers are reachable). Mounting will fail if a problem is
+# detected.
+# Values: Set the time (in ms) you want to spend waiting for the servers
+# (especially the management daemon) to respond. Use 0 to disable all checks
+# and allow mounting even if no servers are reachable.
+# Default: 11000
+
+# [sysSessionCheckOnClose]
+# Checks for a valid session on the storage servers when a file is closed. If
+# this option is set to true, a potential cache loss from a crash of a storage
+# server can be detected. This will be reported to the user application as a
+# close() error code.
+# Note: There is also a session check included in all read/write/fsync messages,
+#    which is independent of this setting.
+# Note: If this option is set to true, more network messages are required on
+#    close(), so performance will decreased.
+# Default: false
+
+# [sysSessionChecksEnabled]
+# Enable session checks in read/write/fsync operations to be able to detect
+# server crashes that could have caused a loss of server side caches. Disabling
+# these checks is useful in certain system configurations to be able to cleanly
+# resume I/O after a server crash/unclean failover.
+# WARNING: Disabling session checks can lead to undetected cache loss and
+# therefore silent data corruption on the storage servers. Only disable the
+# checks if absolutely necessary and if there are measures in place to prevent
+# cache loss (synchronous mounts, battery backed caches) on the storage servers.
+# Default: true
+
+# [sysSyncOnClose]
+# Sync file contents on close. If this option is set to true, the storage
+# servers will flush the write cache of a file to disk immediately when it is
+# closed by the application. If this option is set to false, the write cache
+# will be flushed to disk asynchronously after a few seconds.
+# Note: If this option is true, performance will be decreased.
+# Default: false
+
+# [sysTargetOfflineTimeoutSecs]
+# Timeout until all storage targets and metadata nodes are considered offline
+# when no target state updates can be fetched from the management server.
+# If this value is 0, targets will never be set to offline due to an
+# unreachable management node and will stay in state probably-offline.
+# Note: This must be at least twice as large as the value of
+#    sysTargetOfflineTimoutSecs in the server config files.
+# Values: time in seconds
+# Default: 900
+
+# [sysUpdateTargetStatesSecs]
+# Interval in which the states of the storage targets are checked.
+# Note: This must be significantly shorter than the sysTargetOfflineTimeoutSecs
+# value set in the server (recommendation: maximum 1/3 of it).
+# Values: time in seconds
+# Default: 30
+
+# [sysXAttrsEnabled]
+# Enable extended attributes (also know as EAs/xattrs).
+# Default: false
+
+# [sysXAttrsCheckCapabilities]
+# Check inodes for existing "security.capability" extended attribute and
+# optionally cache to reduce metadata requests and increase write performance.
+# The Linux kernel uses a security mechanism that automatically removes
+# setuid/setgid bits and capabilities from files when they are changed. This is
+# done to prevent users from executing binaries with elevated privileges that
+# were changed after the privileges were originally set. That mechanism requires
+# that, by default, the kernel has to check each file for existing capabilities
+# on every write which leads to a large overhead in metadata RPCs to fetch the
+# "security.capability" extended attribute. To optimize this, Linux allows file
+# systems to set a flag (S_NOSEC) on the file, which short-circuits these
+# checks.
+# This configuration option configures the file system mount to allow the
+# client to either always check, check once and cache that flag after a first
+# lookup of the extended attribute returns an empty result, or set the flag on
+# inode creation and never check. The flag will automatically be cleared when
+# capabilities are modified on this client. It will, however, currently not
+# be cleared when a different client modifies capabilities or sets setuid/setgid
+# bits, which can lead to capabilities not being cleared, even after the file is
+# written to. If this is a concern, this option should be set to "always".
+# As long as BeeGFS is mounted using the "nosuid" mount option (which is
+# recommended and the default setting), elevating privileges via setuid/setgid
+# bits and capabilities is disabled and it is safe to set this option to "never".
+# Possible values:
+#     always  (always check for security xattr, never cache the result)
+#     cache   (check for security xattr once, then cache)
+#     never   (mark new inodes immediately, never check security xattr)
+# Default: never
+
+# [sysBypassFileAccessCheckOnMeta]
+# Allow this client to bypass file access restrictions enforced by metadata
+# servers. When enabled, the client is permitted to open files even if access
+# restrictions are currently in place (e.g., file marked read-only,
+# write-locked, or fully restricted). This setting is primarily intended for
+# specialized clients in controlled environments, such as HSM (Hierarchical
+# Storage Management) systems that need to restore file data, or backup/recovery
+# tools that require access to otherwise locked files.
+# Note: This setting only affects metadata-level access checks and has no effect
+# on other security or permission mechanisms.
+# Default: false
+
+
+# [sysACLsEnabled]
+# Allow the creation and enforcement of Access Control Lists (ACLs).
+# Note: Only works if sysXAttrsEnabled=true.
+# Note: Requires at least Linux kernel version 3.2.
+# Note: Enabling this setting can affect metadata performance.
+# Default: false
+
+# [sysFileEventLogMask]
+# Specifies which file system events shall be logged by the metadata servers. If
+# unset, this client doesn't send log events at all. This can either be "none"
+# or a comma separated list of event types to log. The following event types
+# (and any comma-separated combination) are possible:
+# "flush" (explicit data flushes on files), "close" (close writable file),
+# "trunc" (file truncation), "setattr" (set attributes),
+# "link-op" (create,mkdir,mknod,create symlink,create hardlink,rmdir,unlink, rename),
+# "read" (deprecated, see notes) or "open-read" (file opened in read-only mode),
+# "open-write" (file opened in write only mode),
+# "open-readwrite" (file opened for both read and write),
+# Note: If a client opens a file multiple times, "close" will only generate an
+# event if the last fd is closed. If events for each fd shall be generated,
+# "flush" needs to be used. However, "flush" might have a small performance
+# impact. Also note that "read" is deprecated for file opening in read-only mode,
+# but it is still allowed for backward compatibility. It is recommended to use
+# "open-read" instead of "read" for clarity and consistency.
+# Example: sysFileEventLogMask = close,trunc,setattr,link-op,open-read
+# Default: none
+
+# [sysRenameEbusyAsXdev]
+# Changes the semantics of rename() to return an EXDEV error if a file could not
+# be moved because it is in use (instead of the default EBUSY). Applications and
+# tools like mv can handle EXDEV and fall back to copy/unlink for the files.
+# This is mostly useful for NFS exports, where files may not be closed by the
+# server until after the last open file handle has been closed by clients. This
+# can cause spurious EBUSY errors in clients that close a file and rename it
+# immediately afterwards.
+# Default: false
+
+
+#
+# --- Section 4.5: [Tuning] ---
+#
+
+# [tuneFileCacheType]
+# Sets the file read/write cache type.
+# Values: "none" (disable client caching), "buffered" (use a pool of small
+#    static buffers for write-back and read-ahead), "native" (use the kernel
+#    pagecache), "paged" (experimental, deprecated).
+# Note: The cache protocols are currently non-coherent (but caches are
+#    automatically flushed when a file is closed).
+# Note: When client and servers are running on the same machine, "paged" mode
+#    contains the typical potential for memory allocation deadlocks (also known
+#    from local NFS server mounts). So do not use "paged" mode for clients that
+#    run on a metadata or storage server machine.
+# Default: buffered
+
+# [tunePreferredMetaFile], [tunePreferredStorageFile]
+# Path to a text file that contains the numeric IDs of preferred storage targets
+# and metadata servers. These will be preferred when the client creates new file
+# system entries. This is useful e.g. to take advantage of data locality in the
+# case of multiple data centers. If unspecified, all available targets and
+# servers will be used equally.
+# Usage: One targetID per line for storage servers, one nodeID per line for
+#    metadata servers.
+# Note: TargetIDs and nodeIDs can be queried with the beegfs-ctl tool.
+# Default: <none>
+
+# [tuneRemoteFSync]
+# Controls whether fsync() syscalls from a user application should only be
+# executed on the client to transfer data from the client cache to server
+# cache (=false); or also on the servers to flush the server's cached file
+# data to the disks (=true).
+# Default: true
+
+# [tuneUseGlobalAppendLocks]
+# Controls whether files opened in append mode should be protected by locks on
+# the local machine only (=false) or globally on the servers (=true).
+# Default: false
+
+# [tuneUseGlobalFileLocks]
+# Controls whether application advisory file locks via flock() and fcntl()
+# should be checked for conflicts on the local machine only (=false) or
+# globally on the servers (=true).
+# Default: false
+
+# [tuneCoherentBuffers]
+# Enables or disables coherence between the buffers used by
+# tuneFileCacheType=buffered and the page cache.
+# If a file is concurrently accessed via mmap() regions and read()/write()
+# system calls, the buffers used by tuneFileCacheType=buffered and the page
+# cache used by mmap() may go out of sync - changes made in an mmap()ed region
+# may not be visible to read() calls immediately, or changes made by write()
+# calls may not be immediately reflected in mmap()ed regions.
+# Many programs that use both methods of accessing a file assume that
+# read()/write() and mmap() present the same view of the file, if this is not
+# the case, those programs may not work correctly. Programs that have been
+# observed to misbehave with non-coherent buffers are, for example, git and
+# some in-memory database applications.
+# When this option is enabled, files that are currently mmap()ed will behave as
+# though they had been opened with tuneFileCacheType=none
+# Default: true
+
+
+#
+# --- Section 5: [Expert options]
+#
+
+# [connUnmountRetries]
+# Retry communications during unmount.
+# If this option is set to `true` and a communication error occurs during
+# unmont, for example due to a transient network fault, the unsuccessful
+# communications will be retried normally. When set to `false` they will not be
+# retried; this leads to a quicker unmount, but resources allocated to current
+# client will not be freed for a few hours.
+# Default: true
+
+# [tuneFileCacheBufSize]
+# When using buffered mode: maximum size of the (contiguous) data cache for an
+# open file.
+# When using native mode: threshold for direct operations. If a read() or
+# write() passes a buffer size larger than tuneFileCacheBufSize the client will
+# bypass the page cache and send/receive the data directly to/from the storage
+# servers.
+# Default: 524288 (512KiB)
+
+# [tuneFileCacheBufNum]
+# When using buffered mode: maximum number of file caches to preallocate
+# for the mount. When a file is opened a cache is allocated, up to this number.
+# If the maximum number of caches is reached no cache is allocated and all
+# read/write operations for the file go to the storage servers directly.
+# Default: 4*(number of CPUs)
+
+# [tunePageCacheValidityMS]
+# Maximum lifetime of cached data in the page cache.
+# In buffered mode the page cache is used for mmap(), in native mode the page
+# cache is used for all data. Data in the page cache that was not yet written
+# to the storage server is written after at most this time, data that was read
+# but not modified is discarded.
+# Default: 2000000000 (approx. 23 days)
+
+# [tuneDirSubentryCacheValidityMS]
+# Validity time of directory attribute data, in milliseconds.
+# Attributes of directories (eg stat() data) that have been loaded from the
+# metadata servers are assumed to be valid for this amount of time without
+# requiring a refresh. Once the time has passed the next access will cause a
+# refresh.
+# Default: 1000
+
+# [tuneFileSubentryCacheValidityMS]
+# Validity time of file attribute data, in milliseconds.
+# Attributes of files (eg stat() data) that have been loaded from the metadata
+# servers are assumed to be valid for this amount of time without requiring a
+# refresh. Once the time has passed the next access will cause a refresh.
+# Default: 0
+
+# [tuneENOENTCacheValidityMS]
+# Validity time of the non-existing file in milliseconds.
+# A negative result of a stat call indicating "No such file or directory"
+# (ENOENT) is assumed to be valid for this amount of time without requiring a
+# new request to the meta server. Once the time has passed the next access will
+# cause a refresh.
+# Default: 0
+
+# [tunePathBufSize]
+# Size of buffers used for constructing paths.
+# Whenever a full path must be constructed (eg for log messages) a preallocated
+# buffer of this size will be used.
+# Default: 4096
+
+# [tunePathBufNum]
+# Number of path buffers for path construction.
+# Determines how many path buffers are preallocated during mount. If no buffers
+# are available for an operation the operation must wait for another thread to
+# free enough buffers.
+# Default: 8
+
+# [tuneMsgBufSize]
+# Size of buffers used for messaging.
+# Messages sent and received by the client (except logging messages) use
+# buffers preallocated at mount time. Buffers are allocated with the size
+# given here.
+# Default: 65536
+
+# [tuneMsgBufNum]
+# Number of message buffers.
+# During mount this many message buffers are preallocated. If an operation
+# requires communication with a server but all buffers are used, the operation
+# must wait until a buffer is released.
+# Default: 4*(number of CPUs) + 1
+
+# [tuneRefreshOnGetAttr]
+# If set to `true`, file attributes will be loaded from the server on each call
+# to fstat(). When set to `false` a call to fstat() may return stale
+# information for files that are not currently open; this can happen mainly
+# when NFS exports are used.
+# Default: false
+
+# [tuneInodeBlockBits]
+# Sets the block size of file on the mountpoint to 2**tuneInodeBlockBits.
+# Default: 19 (512KiB)
+
+# [tuneEarlyCloseResponse]
+# Request close responses from the metadata server before the file is fully closed.
+# This may improve close() performance, but closed files may be accounted as
+# open for a short time after close() has returned. Files accounted as open
+# cannot be moved.
+# Default: false
+
+# [tuneUseBufferedAppend]
+# Used only buffered mode. If set, writes to files opened with O_APPEND will be
+# cached. Ignored unless tuneUseGlobalAppendLocks is also set.
+# Default: true
+
+# [tuneStatFsCacheSecs]
+# Validity time of statfs() results, in seconds.
+# Results of statfs(), once queried from the storage servers, will be cached
+# for this amount of time.
+# Default: 10
+
+# [sysInodeIDStyle]
+# Sets the hash function used to compute inode numbers from metadata IDs.
+# The *32 options produce 32 bit inodes numbers, the *64 variants produce 64
+# bit inode numbers.
+# Possible values:
+#   hash32
+#   hash64
+#   md4hash32
+#   md4hash64
+# Default: md4hash64