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DAFILESERVER(8)		     AFS Command Reference	       DAFILESERVER(8)

NAME
       dafileserver - Initializes the File Server component of the dafs
       process

SYNOPSIS
       dafileserver
	   [-auditlog <path to log file>]
	   [-audit-interface (file | sysvmq)]
	   [-d <debug level>]
	   [-p <number of processes>]
	   [-spare <number of spare blocks>]
	   [-pctspare <percentage spare>]
	   [-b <buffers>]
	   [-l <large vnodes>]
	   [-s <small vnodes>]
	   [-vc	<volume	cachesize>]
	   [-w <call back wait interval>]
	   [-cb	<number	of call	backs>]
	   [-banner]
	   [-novbc]
	   [-implicit <admin mode bits:	rlidwka>]
	   [-readonly]
	   [-hr	<number	of hours between refreshing the	host cps>]
	   [-busyat <redirect clients when queue _ n>]
	   [-nobusy]
	   [-rxpck <number of rx extra packets>]
	   [-rxdbg]
	   [-rxdbge]
	   [-rxmaxmtu <bytes>]
	   [-nojumbo]
	   [-jumbo]
	   [-rxbind]
	   [-allow-dotted-principals]
	   [-L]
	   [-S]
	   [-k <stack size>]
	   [-realm <Kerberos realm name>]
	   [-udpsize <size of socket buffer in bytes>]
	   [-sendsize <size of send buffer in bytes>]
	   [-abortthreshold <abort threshold>]
	   [-enable_peer_stats]
	   [-enable_process_stats]
	   [-syslog [< loglevel	>]]
	   [-mrafslogs]
	   [-saneacls]
	   [-help]
	   [-vhandle-setaside <fds reserved for	non-cache io>]
	   [-vhandle-max-cachesize <max	open files>]
	   [-vhandle-initial-cachesize <fds reserved for non-cache io>]
	   [-vattachpar	<number	of volume attach threads>]
	   [-m <min percentage spare in	partition>]
	   [-lock]
	   [-fs-state-dont-save]
	   [-fs-state-dont-restore]
	   [-fs-state-verify] (none | save | restore | both)]
	   [-vhashsize <log(2) of number of volume hash	buckets>]
	   [-vlrudisable]
	   [-vlruthresh	<minutes before	eligibility for	soft detach>]
	   [-vlruinterval <seconds between VLRU	scans>]
	   [-vlrumax <max volumes to soft detach in one	VLRU scan>]
	   [-unsafe-nosalvage]
	   [-offline-timeout <timeout in seconds>]
	   [-offline-shutdown-timeout <timeout in seconds>]

DESCRIPTION
       The dafileserver	command	initializes the	File Server component of the
       "dafs" process. In the conventional configuration, its binary file is
       located in the /usr/local/libexec/openafs directory on a	file server
       machine.

       The dafileserver	command	is not normally	issued at the command shell
       prompt, but rather placed into a	database server	machine's
       /usr/local/etc/openafs/BosConfig	file with the bos create command. If
       it is ever issued at the	command	shell prompt, the issuer must be
       logged onto a file server machine as the	local superuser	"root".

       The File	Server creates the /var/openafs/logs/FileLog log file as it
       initializes, if the file	does not already exist.	It does	not write a
       detailed	trace by default, but the -d option may	be used	to increase
       the amount of detail. Use the bos getlog	command	to display the
       contents	of the log file.

       The command's arguments enable the administrator	to control many
       aspects of the File Server's performance, as detailed in	OPTIONS.  By
       default the File	Server sets values for many arguments that are
       suitable	for a medium-sized file	server machine.	To set values suitable
       for a small or large file server	machine, use the -S or -L flag
       respectively. The following list	describes the parameters and
       corresponding argument for which	the File Server	sets default values,
       and the table below summarizes the setting for each of the three
       machine sizes.

       o   The maximum number of lightweight processes (LWPs) or pthreads the
	   File	Server uses to handle requests for data; corresponds to	the -p
	   argument. The File Server always uses a minimum of 32 KB of memory
	   for these processes.

       o   The maximum number of directory blocks the File Server caches in
	   memory; corresponds to the -b argument. Each	cached directory block
	   (buffer) consumes 2,092 bytes of memory.

       o   The maximum number of large vnodes the File Server caches in	memory
	   for tracking	directory elements; corresponds	to the -l argument.
	   Each	large vnode consumes 292 bytes of memory.

       o   The maximum number of small vnodes the File Server caches in	memory
	   for tracking	file elements; corresponds to the -s argument.	Each
	   small vnode consumes	100 bytes of memory.

       o   The maximum volume cache size, which	determines how many volumes
	   the File Server can cache in	memory before having to	retrieve data
	   from	disk; corresponds to the -vc argument.

       o   The maximum number of callback structures the File Server caches in
	   memory; corresponds to the -cb argument. Each callback structure
	   consumes 16 bytes of	memory.

       o   The maximum number of Rx packets the	File Server uses; corresponds
	   to the -rxpck argument. Each	packet consumes	1544 bytes of memory.

       The default values are:

	 Parameter (Argument)		    Small (-S)	   Medium   Large (-L)
	 ---------------------------------------------------------------------
	 Number	of LWPs	(-p)			    6		9	   128
	 Number	of cached dir blocks (-b)	   70	       90	   120
	 Number	of cached large	vnodes (-l)	  200	      400	   600
	 Number	of cached small	vnodes (-s)	  200	      400	   600
	 Maximum volume	cache size (-vc)	  200	      400	   600
	 Number	of callbacks (-cb)	       20,000	   60,000	64,000
	 Number	of Rx packets (-rxpck)		  100	      150	   200

       To override any of the values, provide the indicated argument (which
       can be combined with the	-S or -L flag).

       The amount of memory required for the File Server varies. The
       approximate default memory usage	is 751 KB when the -S flag is used
       (small configuration), 1.1 MB when all defaults are used	(medium
       configuration), and 1.4 MB when the -L flag is used (large
       configuration). If additional memory is available, increasing the value
       of the -cb and -vc arguments can	improve	File Server performance	most
       directly.

       By default, the File Server allows a volume to exceed its quota by 1 MB
       when an application is writing data to an existing file in a volume
       that is full. The File Server still does	not allow users	to create new
       files in	a full volume. To change the default, use one of the following
       arguments:

       o   Set the -spare argument to the number of extra kilobytes that the
	   File	Server allows as overage. A value of 0 allows no overage.

       o   Set the -pctspare argument to the percentage	of the volume's	quota
	   the File Server allows as overage.

       By default, the File Server implicitly grants the "a" (administer) and
       "l" (lookup) permissions	to system:administrators on the	access control
       list (ACL) of every directory in	the volumes stored on its file server
       machine.	In other words,	the group's members can	exercise those two
       permissions even	when an	entry for the group does not appear on an ACL.
       To change the set of default permissions, use the -implicit argument.

       The File	Server maintains a host	current	protection subgroup (host CPS)
       for each	client machine from which it has received a data access
       request.	Like the CPS for a user, a host	CPS lists all of the
       Protection Database groups to which the machine belongs,	and the	File
       Server compares the host	CPS to a directory's ACL to determine in what
       manner users on the machine are authorized to access the	directory's
       contents. When the pts adduser or pts removeuser	command	is used	to
       change the groups to which a machine belongs, the File Server must
       recompute the machine's host CPS	in order to notice the change. By
       default,	the File Server	contacts the Protection	Server every two hours
       to recompute host CPSs, implying	that it	can take that long for changed
       group memberships to become effective. To change	this frequency,	use
       the -hr argument.

       The File	Server stores volumes in partitions. A partition is a
       filesystem or directory on the server machine that is named "/vicepX"
       or "/vicepXX" where XX is "a" through "z" or "aa" though	"iv". Up to
       255 partitions are allowed. The File Server expects that	the /vicepXX
       directories are each on a dedicated filesystem. The File	Server will
       only use	a /vicepXX if it's a mountpoint	for another filesystem,	unless
       the file	"/vicepXX/AlwaysAttach"	exists.	 A partition will not be
       mounted if the file "/vicepXX/NeverAttach" exists. If both
       "/vicepXX/AlwaysAttach" and "/vicepXX/NeverAttach" are present, then
       "/vicepXX/AlwaysAttach" wins.  The data in the partition	is a special
       format that can only be access using OpenAFS commands or	an OpenAFS
       client.

       The File	Server generates the following message when a partition	is
       nearly full:

	  No space left	on device

       This command does not use the syntax conventions	of the AFS command
       suites. Provide the command name	and all	option names in	full.

CAUTIONS
       There are two strategies	the File Server	can use	for attaching AFS
       volumes at startup and handling volume salvages.	 The traditional
       method assumes all volumes are salvaged before the File Server starts
       and attaches all	volumes	at start before	serving	files.	The newer
       demand-attach method attaches volumes only on demand, salvaging them at
       that time as needed, and	detaches volumes that are not in use.  A
       demand-attach File Server can also save state to	disk for faster
       restarts. The dafileserver implements the demand-attach method, while
       fileserver uses the traditional method.

       The choice of traditional or demand-attach File Server changes the
       required	setup in BosConfig. When changing from a traditional File
       Server to demand-attach or vice versa, you will need to stop and	remove
       the "fs"	or "dafs" node in BosConfig and	create a new node of the
       appropriate type. See bos_create(8) for more information.

       Do not use the -k and -w	arguments, which are intended for use by the
       OpenAFS developers only.	Changing them from their default values	can
       result in unpredictable File Server behavior.  In any case, on many
       operating systems the File Server uses native threads rather than the
       LWP threads, so using the -k argument to	set the	number of LWP threads
       has no effect.

       Do not specify both the -spare and -pctspare arguments. Doing so	causes
       the File	Server to exit,	leaving	an error message in the
       /var/openafs/logs/FileLog file.

       Options that are	available only on some system types, such as the -m
       and -lock options, appear in the	output generated by the	-help option
       only on the relevant system type.

       Currently, the maximum size of a	volume quota is	2 terabytes (2^41
       bytes) and the maximum size of a	/vicepX	partition on a fileserver is
       2^64 kilobytes. The maximum partition size in releases 1.4.7 and
       earlier is 2 terabytes (2^31 bytes). The	maximum	partition size for
       1.5.x releases 1.5.34 and earlier is 2 terabytes	as well.

       The maximum number of directory entries is 64,000 if all	of the entries
       have names that are 15 octets or	less in	length.	A name that is 15
       octets long requires the	use of only one	block in the directory.
       Additional sequential blocks are	required to store entries with names
       that are	longer than 15 octets. Each additional block provides an
       additional length of 32 octets for the name of the entry. Note that if
       file names use an encoding like UTF-8, a	single character may be
       encoded into multiple octets.

       In real world use, the maximum number of	objects	in an AFS directory is
       usually between 16,000 and 25,000, depending on the average name
       length.

OPTIONS
       -auditlog <log path>
	   Turns on audit logging, and sets the	path for the audit log.	 The
	   audit log records information about RPC calls, including the	name
	   of the RPC call, the	host that submitted the	call, the
	   authenticated entity	(user) that issued the call, the parameters
	   for the call, and if	the call succeeded or failed.

       -audit-interface	(file |	sysvmq)
	   Specifies what audit	interface to use. The "file" interface writes
	   audit messages to the file passed to	-auditlog. The "sysvmq"
	   interface writes audit messages to a	SYSV message (see msgget(2)
	   and msgrcv(2)). The message queue the "sysvmq" interface writes to
	   has the key "ftok(path, 1)",	where "path" is	the path specified in
	   the -auditlog option.

	   Defaults to "file".

       -d <debug level>
	   Sets	the detail level for the debugging trace written to the
	   /var/openafs/logs/FileLog file. Provide one of the following
	   values, each	of which produces an increasingly detailed trace: 0,
	   1, 5, 25, and 125. The default value	of 0 produces only a few
	   messages.

       -p <number of processes>
	   Sets	the number of threads (or LWPs)	to run.	Provide	a positive
	   integer.  The File Server creates and uses five threads for special
	   purposes, in	addition to the	number specified (but if this argument
	   specifies the maximum possible number, the File Server
	   automatically uses five of the threads for its own purposes).

	   The maximum number of threads can differ in each release of
	   OpenAFS.  Consult the OpenAFS Release Notes for the current
	   release.

       -spare <number of spare blocks>
	   Specifies the number	of additional kilobytes	an application can
	   store in a volume after the quota is	exceeded. Provide a positive
	   integer; a value of 0 prevents the volume from ever exceeding its
	   quota. Do not combine this argument with the	-pctspare argument.

       -pctspare <percentage spare>
	   Specifies the amount	by which the File Server allows	a volume to
	   exceed its quota, as	a percentage of	the quota. Provide an integer
	   between 0 and 99. A value of	0 prevents the volume from ever
	   exceeding its quota.	Do not combine this argument with the -spare
	   argument.

       -b <buffers>
	   Sets	the number of directory	buffers. Provide a positive integer.

       -l <large vnodes>
	   Sets	the number of large vnodes available in	memory for caching
	   directory elements. Provide a positive integer.

       -s <small nodes>
	   Sets	the number of small vnodes available in	memory for caching
	   file	elements. Provide a positive integer.

       -vc <volume cachesize>
	   Sets	the number of volumes the File Server can cache	in memory.
	   Provide a positive integer.

       -w <call	back wait interval>
	   Sets	the interval at	which the daemon spawned by the	File Server
	   performs its	maintenance tasks. Do not use this argument; changing
	   the default value can cause unpredictable behavior.

       -cb <number of callbacks>
	   Sets	the number of callbacks	the File Server	can track. Provide a
	   positive integer.

       -banner
	   Prints the following	banner to /dev/console about every 10 minutes.

	      File Server is running at	I<time>.

       -novbc
	   Prevents the	File Server from breaking the callbacks	that Cache
	   Managers hold on a volume that the File Server is reattaching after
	   the volume was offline (as a	result of the vos restore command, for
	   example). Use of this flag is strongly discouraged.

       -implicit <admin	mode bits>
	   Defines the set of permissions granted by default to	the
	   system:administrators group on the ACL of every directory in	a
	   volume stored on the	file server machine. Provide one or more of
	   the standard	permission letters ("rlidwka") and auxiliary
	   permission letters ("ABCDEFGH"), or one of the shorthand notations
	   for groups of permissions ("all", "none", "read", and "write"). To
	   review the meaning of the permissions, see the fs setacl reference
	   page.

       -readonly
	   Don't allow writes to this fileserver.

       -hr <number of hours between refreshing the host	cps>
	   Specifies how often the File	Server refreshes its knowledge of the
	   machines that belong	to protection groups (refreshes	the host CPSs
	   for machines). The File Server must update this information to
	   enable users	from machines recently added to	protection groups to
	   access data for which those machines	now have the necessary ACL
	   permissions.

       -busyat <redirect clients when queue _ n>
	   Defines the number of incoming RPCs that can	be waiting for a
	   response from the File Server before	the File Server	returns	the
	   error code "VBUSY" to the Cache Manager that	sent the latest	RPC.
	   In response,	the Cache Manager retransmits the RPC after a delay.
	   This	argument prevents the accumulation of so many waiting RPCs
	   that	the File Server	can never process them all. Provide a positive
	   integer.  The default value is 600.

       -rxpck <number of rx extra packets>
	   Controls the	number of Rx packets the File Server uses to store
	   data	for incoming RPCs that it is currently handling, that are
	   waiting for a response, and for replies that	are not	yet complete.
	   Provide a positive integer.

       -rxdbg
	   Writes a trace of the File Server's operations on Rx	packets	to the
	   file	/var/openafs/logs/rx_dbg.

       -rxdbge
	   Writes a trace of the File Server's operations on Rx	events (such
	   as retransmissions) to the file /var/openafs/logs/rx_dbg.

       -rxmaxmtu <bytes>
	   Defines the maximum size of an MTU.	The value must be between the
	   minimum and maximum packet data sizes for Rx.

       -jumbo
	   Allows the server to	send and receive jumbograms. A jumbogram is a
	   large-size packet composed of 2 to 4	normal Rx data packets that
	   share the same header. The fileserver does not use jumbograms by
	   default, as some routers are	not capable of properly	breaking the
	   jumbogram into smaller packets and reassembling them.

       -nojumbo
	   Deprecated; jumbograms are disabled by default.

       -rxbind
	   Force the fileserver	to only	bind to	one IP address.

       -allow-dotted-principals
	   By default, the RXKAD security layer	will disallow access by
	   Kerberos principals with a dot in the first component of their
	   name. This is to avoid the confusion	where principals user/admin
	   and user.admin are both mapped to the user.admin PTS	entry. Sites
	   whose Kerberos realms don't have these collisions between principal
	   names may disable this check	by starting the	server with this
	   option.

       -L  Sets	values for many	arguments in a manner suitable for a large
	   file	server machine.	Combine	this flag with any option except the
	   -S flag; omit both flags to set values suitable for a medium-sized
	   file	server machine.

       -S  Sets	values for many	arguments in a manner suitable for a small
	   file	server machine.	Combine	this flag with any option except the
	   -L flag; omit both flags to set values suitable for a medium-sized
	   file	server machine.

       -k <stack size>
	   Sets	the LWP	stack size in units of 1 kilobyte. Do not use this
	   argument, and in particular do not specify a	value less than	the
	   default of 24.

       -realm <Kerberos	realm name>
	   Defines the Kerberos	realm name for the File	Server to use. If this
	   argument is not provided, it	uses the realm name corresponding to
	   the cell listed in the local	/usr/local/etc/openafs/server/ThisCell
	   file.

       -udpsize	<size of socket	buffer in bytes>
	   Sets	the size of the	UDP buffer, which is 64	KB by default. Provide
	   a positive integer, preferably larger than the default.

       -sendsize <size of send buffer in bytes>
	   Sets	the size of the	send buffer, which is 16384 bytes by default.

       -abortthreshold <abort threshold>
	   Sets	the abort threshold, which is triggered	when an	AFS client
	   sends a number of FetchStatus requests in a row and all of them
	   fail	due to access control or some other error. When	the abort
	   threshold is	reached, the file server starts	to slow	down the
	   responses to	the problem client in order to reduce the load on the
	   file	server.

	   The throttling behaviour can	cause issues especially	for some
	   versions of the Windows OpenAFS client. When	using Windows Explorer
	   to navigate the AFS directory tree, directories with	only "look"
	   access for the current user may load	more slowly because of the
	   throttling. This is because the Windows OpenAFS client sends
	   FetchStatus calls one at a time instead of in bulk like the Unix
	   Open	AFS client.

	   Setting the threshold to 0 disables the throttling behavior.	This
	   option is available in OpenAFS versions 1.4.1 and later.

       -enable_peer_stats
	   Activates the collection of Rx statistics and allocates memory for
	   their storage. For each connection with a specific UDP port on
	   another machine, a separate record is kept for each type of RPC
	   (FetchFile, GetStatus, and so on) sent or received. To display or
	   otherwise access the	records, use the Rx Monitoring API.

       -enable_process_stats
	   Activates the collection of Rx statistics and allocates memory for
	   their storage. A separate record is kept for	each type of RPC
	   (FetchFile, GetStatus, and so on) sent or received, aggregated over
	   all connections to other machines. To display or otherwise access
	   the records,	use the	Rx Monitoring API.

       -syslog [<loglevel]
	   Use syslog instead of the normal logging location for the
	   fileserver process.	If provided, log messages are at <loglevel>
	   instead of the default LOG_USER.

       -mrafslogs
	   Use MR-AFS (Multi-Resident) style logging.  This option is
	   deprecated.

       -saneacls
	   Offer the SANEACLS capability for the fileserver.  This option is
	   currently unimplemented.

       -help
	   Prints the online help for this command. All	other valid options
	   are ignored.

       -vhandle-setaside <fds reserved for non-cache io>
	   Number of file handles set aside for	I/O not	in the cache. Defaults
	   to 128.

       -vhandle-max-cachesize <max open	files>
	   Maximum number of available file handles.

       -vhandle-initial-cachesize <initial open	file cache>
	   Number of file handles set aside for	I/O in the cache. Defaults to
	   128.

       -vattachpar <number of volume attach threads>
	   The number of threads assigned to attach and	detach volumes.	 The
	   default is 1.  Warning: many	of the I/O parallelism features	of
	   Demand-Attach Fileserver are	turned off when	the number of volume
	   attach threads is only 1.

	   This	option is only meaningful for a	file server built with
	   pthreads support.

       -m <min percentage spare	in partition>
	   Specifies the percentage of each AFS	server partition that the AIX
	   version of the File Server creates as a reserve. Specify an integer
	   value between 0 and 30; the default is 8%. A	value of 0 means that
	   the partition can become completely full, which can have serious
	   negative consequences.  This	option is not supported	on platforms
	   other than AIX.

       -lock
	   Prevents any	portion	of the fileserver binary from being paged
	   (swapped) out of memory on a	file server machine running the	IRIX
	   operating system.  This option is not supported on platforms	other
	   than	IRIX.

       -sync <always | delayed | onclose | never>
	   This	option changes how hard	the fileserver tries to	ensure that
	   data	written	to volumes actually hits the physical disk.

	   Normally, when the fileserver writes	to disk, the underlying
	   filesystem or Operating System may delay writes from	actually going
	   to disk, and	reorder	which writes hit the disk first. So, during an
	   unclean shutdown of the machine (if the power goes out, or the
	   machine crashes, etc), or if	the physical disk backing store
	   becomes unavailable,	file data may become lost that the server
	   previously told clients was already successfully written.

	   To try to mitigate this, the	fileserver will	try to "sync" file
	   data	to the physical	disk at	numerous points	during various I/O.
	   However, this can result in significantly reduced performance.
	   Depending on	the usage patterns, this may or	may not	be acceptable.
	   This	option dictates	specifically what the fileserver does when it
	   wants to perform a "sync".

	   There are several options; pass one of these	as the argument	to
	   -sync. The default is "onclose".

	   always
	       This causes a sync operation to always sync immediately and
	       synchronously.  This is the slowest option that provides	the
	       greatest	protection against data	loss in	the event of a crash
	       or backing store	unavailability.

	       Note that this is still not a 100% guarantee that data will not
	       be lost or corrupted during a crash. The	underlying filesystem
	       itself may cause	data to	be lost	or corrupt in such a
	       situation. And OpenAFS itself does not (yet) even guarantee
	       that all	data is	consistent at any point	in time; so even if
	       the filesystem and OS do	not buffer or reorder any writes, you
	       are not guaranteed that all data	will be	okay after a crash.

	       This option may be appropriate if you have reason to believe a
	       server is prone to data loss failures, such as if the server
	       encounters frequent power failures or connectivity issues with
	       network attached	storage. Or if the backend storage is
	       temporarily degraded in some way	(for example, a	battery	on a
	       caching controller fails), it may make sense to temporarily use
	       the "always" option until the situation is fixed. Some servers
	       may also	allow for sync operations to occur very	quickly, such
	       that the	"always" option	is not noticeably slower than any
	       other option. In	such a case, there is no downside to
	       specifying "always".

	       This was	the only behavior allowed in OpenAFS releases prior to
	       1.4.5.

	   delayed
	       This causes a sync to do	nothing	immediately, but the sync will
	       happen sometime in the background, within approximately the
	       next 10 seconds.	This works by having a separate	thread that
	       goes through all	open file handles every	10 seconds, and	it
	       syncs the ones that have	been marked as needing a sync. File
	       handles flagged for sync	may also get synced on volume
	       detachment, according to	the same behavior as with the
	       "onclose" option.

	       This option is currently	not recommended, since in the past the
	       code implementing this option has caused	rare data corruption
	       during normal operation.

	       This was	the only behavior allowed in OpenAFS releases starting
	       from 1.4.5 up to	and including 1.6.2. It	was the	default
	       starting	from OpenAFS 1.6.3 up to and including OpenAFS 1.6.7.
	       This option will	be removed in a	future version of OpenAFS.

	   onclose
	       This causes a sync to do	nothing	immediately, but causes	the
	       relevant	file to	be flagged as potentially needing a sync. When
	       a volume	is detached, flagged volume metadata files are synced,
	       as well as data files that have been accessed recently. Events
	       that cause a volume to detach include: performing certain
	       volume operations (restore, salvage, offline, et	al), detection
	       of volume consistency errors, a clean shutdown of the
	       fileserver, or during DAFS "soft	detachment".

	       Effectively this	option is the same as "never" while a volume
	       is attached and actively	being used, but	if a volume is
	       detached, there is an additional	guarantee for the data's
	       consistency.

	       This option is the default starting with	OpenAFS	1.6.8.

	   never
	       This causes all syncs to	never do anything. This	is the fastest
	       option, with the	weakest	guarantees for data consistency.

	       Depending on the	underlying filesystem and Operating System,
	       there may be guarantees that any	data written to	disk will hit
	       the physical media after	a certain amount of time. For example,
	       Linux's pdflush process usually makes this guarantee, and ext3
	       can make	certain	various	consistency guarantees according to
	       the options given. ZFS on Solaris can also provide similar
	       guarantees, as can various other	platforms and filesystems.
	       Consult the documentation for your platform if you are unsure.

	   Which option	you choose is not an easy decision to make. Various
	   developers and experts sometimes disagree on	which option is	the
	   most	reasonable, and	it may depend on the specific scenario and
	   workload involved. Some argue that the "always" option does not
	   provide significantly greater guarantees over any other option,
	   whereas others argue	that choosing anything besides the "always"
	   option allows for an	unacceptable risk of data loss.	This may
	   depend on your usage	patterns, your hardware, your platform and
	   filesystem, and who you talk	to about this topic.

       -offline-timeout	<timeout in seconds>
	   Setting this	option to N means that if any clients are reading from
	   a volume when we want to offline that volume	(for example, as part
	   of releasing	a volume), we will wait	N seconds for the clients'
	   request to finish. If the clients' requests have not	finished, we
	   will	then interrupt the client requests and send an error to	those
	   clients, allowing the volume	to go offline.

	   If a	client is interrupted, from the	client's point of view,	it
	   will	appear as if they had accessed the volume after	it had gone
	   offline. For	RO volumes, this mean the client should	fail-over to
	   other valid RO sites	for that volume. This option may speed up
	   volume releases if volumes are being	accessed by clients that have
	   slow	or unreliable network connections.

	   Setting this	option to 0 means to interrupt clients immediately if
	   a volume is waiting to go offline. Setting this option to "-1"
	   means to wait forever for client requests to	finish.	The default
	   value is "-1".

	   For the LWP fileserver, the only valid value	for this option	is
	   "-1".

       -offline-shutdown-timeout <timeout in seconds>
	   This	option behaves similarly to -offline-timeout but applies to
	   volumes that	are going offline as part of the fileserver shutdown
	   process. If the value specified is N, we will interrupt any clients
	   reading from	volumes	after N	seconds	have passed since we first
	   needed to wait for a	volume to offline during the shutdown process.

	   Setting this	option to 0 means to interrupt all clients reading
	   from	volumes	immediately during the shutdown	process. Setting this
	   option to "-1" means	to wait	forever	for client requests to finish
	   during the shutdown process.

	   If -offline-timeout is specified, the default value of
	   -offline-shutdown-timeout is	the value specified for
	   -offline-timeout. Otherwise,	the default value is "-1".

	   For the LWP fileserver, the only valid value	for this option	is
	   "-1".

       -fs-state-dont-save
	   When	present, fileserver state will not be saved during shutdown.
	   Default is to save state.

       -fs-state-dont-restore
	   When	present, fileserver state will not be restored during startup.
	   Default is to restore state on startup.

       -fs-state-verify	(none |	save | restore | both)
	   This	argument controls the behavior of the state verification
	   mechanism.  A value of "none" turns off all verification.  A	value
	   of "save" only performs the verification steps prior	to saving
	   state to disk.  A value of "restore"	only performs the verification
	   steps after restoring state from disk.  A value of "both" performs
	   all verifications steps both	prior to save and following a restore.

	   The default is "both".

       -vhashsize <size
	   The log(2) number of	of volume hash buckets.	 Default is 8 (i.e.,
	   by default, there are 2^8 = 256 volume hash buckets). The minimum
	   that	can be specified is 6 (64 hash buckets). In OpenAFS 1.5.77 and
	   earlier, the	maximum	that can be specified is 14 (16384 buckets).
	   After 1.5.77, the maximum that can be specified is 28 (268435456
	   buckets).

       -vlruthresh <minutes
	   The number of minutes of inactivity before a	volume is eligible for
	   soft	detachment.  Default is	120 minutes.

       -vlruinterval <seconds
	   The number of seconds between VLRU candidate	queue scan.  The
	   default is 120 seconds.

       -vlrumax	<positive integer
	   The maximum number of volumes which can be soft detached in a
	   single pass of the scanner.	Default	is 8 volumes.

       -unsafe-nosalvage
	   This	option causes the fileserver to	bypass the normal safety check
	   when	attaching volumes that checks the inUse	field in the volume
	   header. With	this option, volumes that were in use at the time of
	   an unclean shutdown will not	be salvaged immediately	the next time
	   they	are accessed, and thus risk (possibly silent and/or
	   irrevocable)	corruption. Volumes will still be salvaged when	an
	   internal inconsistency is detected or other cases where a salvage
	   would normally occur.

	   Due to the increased	risk of	data corruption, the use of this flag
	   is strongly discouraged. Only use it	if you really know what	you
	   are doing.

EXAMPLES
       The following bos create	command	creates	a dafs process on the file
       server machine "fs2.abc.com" that uses the large	configuration size,
       and allows volumes to exceed their quota	by 10%.	Type the command on a
       single line:

	  % bos	create -server fs2.abc.com -instance dafs -type	dafs \
		       -cmd "/usr/local/libexec/openafs/dafileserver -pctspare 10 -L" \
		       /usr/local/libexec/openafs/davolserver \
		       /usr/local/libexec/openafs/salvageserver	\
		       /usr/local/libexec/openafs/dasalvager

TROUBLESHOOTING
       Sending process signals to the File Server Process can change its
       behavior	in the following ways:

	 Process	  Signal       OS     Result
	 ---------------------------------------------------------------------

	 File Server	  XCPU	      Unix    Prints a list of client IP
					      Addresses.

	 File Server	  USR2	    Windows   Prints a list of client IP
					      Addresses.

	 File Server	  POLL	      HPUX    Prints a list of client IP
					      Addresses.

	 Any server	  TSTP	      Any     Increases	Debug level by a power
					      of 5 -- 1,5,25,125, etc.
					      This has the same	effect as the
					      -d XXX command-line option.

	 Any Server	  HUP	      Any     Resets Debug level to 0

	 File Server	  TERM	      Any     Run minor	instrumentation	over
					      the list of descriptors.

	 Other Servers	  TERM	      Any     Causes the process to quit.

	 File Server	  QUIT	      Any     Causes the File Server to	Quit.
					      Bos Server knows this.

       The basic metric	of whether an AFS file server is doing well is the
       number of connections waiting for a thread, which can be	found by
       running the following command:

	  % rxdebug <server> | grep waiting_for	| wc -l

       Each line returned by "rxdebug" that contains the text "waiting_for"
       represents a connection that's waiting for a file server	thread.

       If the blocked connection count is ever above 0,	the server is having
       problems	replying to clients in a timely	fashion.  If it	gets above 10,
       roughly,	there will be noticeable slowness by the user.	The total
       number of connections is	a mostly irrelevant number that	goes
       essentially monotonically for as	long as	the server has been running
       and then	goes back down to zero when it's restarted.

       The most	common cause of	blocked	connections rising on a	server is some
       process somewhere performing an abnormal	number of accesses to that
       server and its volumes.	If multiple servers have a blocked connection
       count, the most likely explanation is that there	is a volume replicated
       between those servers that is absorbing an abnormally high access rate.

       To get an access	count on all the volumes on a server, run:

	  % vos	listvol	<server> -long

       and save	the output in a	file.  The results will	look like a bunch of
       vos examine output for each volume on the server.  Look for lines like:

	  40065	accesses in the	past day (i.e.,	vnode references)

       and look	for volumes with an abnormally high number of accesses.
       Anything	over 10,000 is fairly high, but	some volumes like root.cell
       and other volumes close to the root of the cell will have that many
       hits routinely.	Anything over 100,000 is generally abnormally high.
       The count resets	about once a day.

       Another approach	that can be used to narrow the possibilities for a
       replicated volume, when multiple	servers	are having trouble, is to find
       all replicated volumes for that server.	Run:

	  % vos	listvldb -server <server>

       where <server> is one of	the servers having problems to refresh the
       VLDB cache, and then run:

	  % vos	listvldb -server <server> -part	<partition>

       to get a	list of	all volumes on that server and partition, including
       every other server with replicas.

       Once the	volume causing the problem has been identified,	the best way
       to deal with the	problem	is to move that	volume to another server with
       a low load or to	stop any runaway programs that are accessing that
       volume unnecessarily.  Often the	volume will be enough information to
       tell what's going on.

       If you still need additional information	about who's hitting that
       server, sometimes you can guess at that information from	the failed
       callbacks in the	FileLog	log in /var/log/afs on the server, or from the
       output of:

	  % /usr/afsws/etc/rxdebug <server> -rxstats

       but the best way	is to turn on debugging	output from the	file server.
       (Warning: This generates	a lot of output	into FileLog on	the AFS
       server.)	 To do this, log on to the AFS server, find the	PID of the
       fileserver process, and do:

	   kill	-TSTP <pid>

       where <pid> is the PID of the file server process.  This	will raise the
       debugging level so that you'll start seeing what	people are actually
       doing on	the server.  You can do	this up	to three more times to get
       even more output	if needed.  To reset the debugging level back to
       normal, use (The	following command will NOT terminate the file server):

	   kill	-HUP <pid>

       The debugging setting on	the File Server	should be reset	back to	normal
       when debugging is no longer needed.  Otherwise, the AFS server may well
       fill its	disks with debugging output.

       The lines of the	debugging output that are most useful for debugging
       load problems are:

	   SAFS_FetchStatus,  Fid = 2003828163.77154.82248, Host 171.64.15.76
	   SRXAFS_FetchData, Fid = 2003828163.77154.82248

       (The example above is partly truncated to highlight the interesting
       information).  The Fid identifies the volume and	inode within the
       volume; the volume is the first long number.  So, for example, this
       was:

	  % vos	examine	2003828163
	  pubsw.matlab61		   2003828163 RW    1040060 K  On-line
	      afssvr5.Stanford.EDU /vicepa
	      RWrite 2003828163	ROnly 2003828164 Backup	2003828165
	      MaxQuota	  3000000 K
	      Creation	  Mon Aug  6 16:40:55 2001
	      Last Update Tue Jul 30 19:00:25 2002
	      86181 accesses in	the past day (i.e., vnode references)

	      RWrite: 2003828163    ROnly: 2003828164	 Backup: 2003828165
	      number of	sites -> 3
		 server	afssvr5.Stanford.EDU partition /vicepa RW Site
		 server	afssvr11.Stanford.EDU partition	/vicepd	RO Site
		 server	afssvr5.Stanford.EDU partition /vicepa RO Site

       and from	the Host information one can tell what system is accessing
       that volume.

       Note that the output of vos_examine(1) also includes the	access count,
       so once the problem has been identified,	vos examine can	be used	to see
       if the access count is still increasing.	 Also remember that you	can
       run vos examine on the read-only	replica	(e.g.,
       pubsw.matlab61.readonly)	to see the access counts on the	read-only
       replica on all of the servers that it's located on.

PRIVILEGE REQUIRED
       The issuer must be logged in as the superuser "root" on a file server
       machine to issue	the command at a command shell prompt.	It is
       conventional instead to create and start	the process by issuing the bos
       create command.

SEE ALSO
       BosConfig(5), FileLog(5), bos_create(8),	bos_getlog(8), fs_setacl(1),
       msgget(2), msgrcv(2), salvager(8), volserver(8),	vos_examine(1)

COPYRIGHT
       IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

       This documentation is covered by	the IBM	Public License Version 1.0.
       It was converted	from HTML to POD by software written by	Chas Williams
       and Russ	Allbery, based on work by Alf Wachsmann	and Elizabeth Cassell.

OpenAFS				  2016-12-15		       DAFILESERVER(8)

NAME | SYNOPSIS | DESCRIPTION | CAUTIONS | OPTIONS | EXAMPLES | TROUBLESHOOTING | PRIVILEGE REQUIRED | SEE ALSO | COPYRIGHT

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