3 fileserver - Initializes the File Server component of the fs process
10 B<fileserver> S<<< [B<-auditlog> <I<log path>>] >>>
11 S<<< [B<-d> <I<debug level>>] >>>
12 S<<< [B<-p> <I<number of processes>>] >>>
13 S<<< [B<-spare> <I<number of spare blocks>>] >>>
14 S<<< [B<-pctspare> <I<percentage spare>>] >>> S<<< [B<-b> <I<buffers>>] >>>
15 S<<< [B<-l> <I<large vnodes>>] >>> S<<< [B<-s> <I<small nodes>>] >>>
16 S<<< [B<-vc> <I<volume cachesize>>] >>> S<<< [B<-w> <I<call back wait interval>>] >>>
17 S<<< [B<-cb> <I<number of call backs>>] >>> [B<-banner>] [B<-novbc>]
18 S<<< [B<-implicit> <I<admin mode bits: rlidwka>>] >>> [B<-readonly>]
19 S<<< [B<-hr> <I<number of hours between refreshing the host cps>>] >>>
20 S<<< [B<-busyat> <I<< redirect clients when queue > n >>>] >>>
21 [B<-nobusy>] S<<< [B<-rxpck> <I<number of rx extra packets>>] >>>
22 [B<-rxdbg>] [B<-rxdbge>] S<<< [B<-rxmaxmtu> <I<bytes>>] >>>
23 S<<< [B<-rxbind> <I<address to bind the Rx socket to>>] >>>
24 S<<< [B<-vattachpar> <I<number of volume attach threads>>] >>>
25 S<<< [B<-m> <I<min percentage spare in partition>>] >>>
26 [B<-lock>] [B<-L>] [B<-S>] S<<< [B<-k> <I<stack size>>] >>>
27 S<<< [B<-realm> <I<Kerberos realm name>>] >>>
28 S<<< [B<-udpsize> <I<size of socket buffer in bytes>>] >>>
29 S<<< [B<-sendsize> <I<size of send buffer in bytes>>] >>>
30 S<<< [B<-abortthreshold> <I<abort threshold>>] >>>
31 S<<< [B<-auditlog> <I<path to log file>>] >>>
32 [B<-enable_peer_stats>] [B<-enable_process_stats>] [B<-help>]
39 The B<fileserver> command initializes the File Server component of the
40 C<fs> process. In the conventional configuration, its binary file is
41 located in the F</usr/afs/bin> directory on a file server machine.
43 The B<fileserver> command is not normally issued at the command shell
44 prompt, but rather placed into a database server machine's
45 F</usr/afs/local/BosConfig> file with the B<bos create> command. If it is
46 ever issued at the command shell prompt, the issuer must be logged onto a
47 file server machine as the local superuser C<root>.
49 The File Server creates the F</usr/afs/logs/FileLog> log file as it
50 initializes, if the file does not already exist. It does not write a
51 detailed trace by default, but the B<-d> option may be used to
52 increase the amount of detail. Use the B<bos getlog> command to
53 display the contents of the log file.
55 The command's arguments enable the administrator to control many aspects
56 of the File Server's performance, as detailed in L<OPTIONS>. By default
57 the B<fileserver> command sets values for many arguments that are suitable
58 for a medium-sized file server machine. To set values suitable for a small
59 or large file server machine, use the B<-S> or B<-L> flag
60 respectively. The following list describes the parameters and
61 corresponding argument for which the B<fileserver> command sets default
62 values, and the table below summarizes the setting for each of the three
69 The maximum number of lightweight processes (LWPs) the File Server uses to
70 handle requests for data; corresponds to the B<-p> argument. The File
71 Server always uses a minimum of 32 KB of memory for these processes.
75 The maximum number of directory blocks the File Server caches in memory;
76 corresponds to the B<-b> argument. Each cached directory block (buffer)
77 consumes 2,092 bytes of memory.
81 The maximum number of large vnodes the File Server caches in memory for
82 tracking directory elements; corresponds to the B<-l> argument. Each large
83 vnode consumes 292 bytes of memory.
87 The maximum number of small vnodes the File Server caches in memory for
88 tracking file elements; corresponds to the B<-s> argument. Each small
89 vnode consumes 100 bytes of memory.
93 The maximum volume cache size, which determines how many volumes the File
94 Server can cache in memory before having to retrieve data from disk;
95 corresponds to the B<-vc> argument.
99 The maximum number of callback structures the File Server caches in
100 memory; corresponds to the B<-cb> argument. Each callback structure
101 consumes 16 bytes of memory.
105 The maximum number of Rx packets the File Server uses; corresponds to the
106 B<-rxpck> argument. Each packet consumes 1544 bytes of memory.
110 The default values are:
112 Parameter (Argument) Small (-S) Medium Large (-L)
113 ---------------------------------------------------------------------
114 Number of LWPs (-p) 6 9 12
115 Number of cached dir blocks (-b) 70 90 120
116 Number of cached large vnodes (-l) 200 400 600
117 Number of cached small vnodes (-s) 200 400 600
118 Maximum volume cache size (-vc) 200 400 600
119 Number of callbacks (-cb) 20,000 60,000 64,000
120 Number of Rx packets (-rxpck) 100 150 200
122 To override any of the values, provide the indicated argument (which can
123 be combined with the B<-S> or B<-L> flag).
125 The amount of memory required for the File Server varies. The approximate
126 default memory usage is 751 KB when the B<-S> flag is used (small
127 configuration), 1.1 MB when all defaults are used (medium configuration),
128 and 1.4 MB when the B<-L> flag is used (large configuration). If
129 additional memory is available, increasing the value of the B<-cb> and
130 B<-vc> arguments can improve File Server performance most directly.
132 By default, the File Server allows a volume to exceed its quota by 1 MB
133 when an application is writing data to an existing file in a volume that
134 is full. The File Server still does not allow users to create new files in
135 a full volume. To change the default, use one of the following arguments:
141 Set the B<-spare> argument to the number of extra kilobytes that the File
142 Server allows as overage. A value of C<0> allows no overage.
146 Set the B<-pctspare> argument to the percentage of the volume's quota the
147 File Server allows as overage.
151 By default, the File Server implicitly grants the C<a> (administer) and
152 C<l> (lookup) permissions to system:administrators on the access control
153 list (ACL) of every directory in the volumes stored on its file server
154 machine. In other words, the group's members can exercise those two
155 permissions even when an entry for the group does not appear on an ACL. To
156 change the set of default permissions, use the B<-implicit> argument.
158 The File Server maintains a I<host current protection subgroup> (I<host
159 CPS>) for each client machine from which it has received a data access
160 request. Like the CPS for a user, a host CPS lists all of the Protection
161 Database groups to which the machine belongs, and the File Server compares
162 the host CPS to a directory's ACL to determine in what manner users on the
163 machine are authorized to access the directory's contents. When the B<pts
164 adduser> or B<pts removeuser> command is used to change the groups to
165 which a machine belongs, the File Server must recompute the machine's host
166 CPS in order to notice the change. By default, the File Server contacts
167 the Protection Server every two hours to recompute host CPSs, implying
168 that it can take that long for changed group memberships to become
169 effective. To change this frequency, use the B<-hr> argument.
171 The File Server stores volumes in partitions. A partition is a
172 filesystem or directory on the server machine that is named C</vicepX>
173 or C</vicepXX> where XX is "a" through "z" or "aa" though "zz". The
174 File Server expects that the /vicepXX directories are each on a
175 dedicated filesystem. The File Server will only use a /vicepXX if it's
176 a mountpoint for another filesystem, unless the file
177 C</vicepXX/AlwaysAttach> exists. The data in the partition is a
178 special format that can only be access using OpenAFS commands or an
181 The File Server generates the following message when a partition is nearly
184 No space left on device
186 This command does not use the syntax conventions of the AFS command
187 suites. Provide the command name and all option names in full.
191 Do not use the B<-k> and B<-w> arguments, which are intended for use
192 by the AFS Development group only. Changing them from their default
193 values can result in unpredictable File Server behavior. In any case,
194 on many operating systems the File Server uses native threads rather
195 than the LWP threads, so using the B<-k> argument to set the number of
196 LWP threads has no effect.
198 Do not specify both the B<-spare> and B<-pctspare> arguments. Doing so
199 causes the File Server to exit, leaving an error message in the
200 F</usr/afs/logs/FileLog> file.
202 Options that are available only on some system types, such as the B<-m>
203 and B<-lock> options, appear in the output generated by the B<-help>
204 option only on the relevant system type.
210 =item B<-auditlog> <I<log path>>
212 Set and enable auditing.
214 =item B<-d> <I<debug level>>
216 Sets the detail level for the debugging trace written to the
217 F</usr/afs/logs/FileLog> file. Provide one of the following values, each
218 of which produces an increasingly detailed trace: C<0>, C<1>, C<5>, C<25>,
219 and C<125>. The default value of C<0> produces only a few messages.
221 =item B<-p> <I<number of processes>>
223 Sets the number of threads to run. Provide a positive integer. The File
224 Server creates and uses five threads for special purposes, in addition to
225 the number specified (but if this argument specifies the maximum possible
226 number, the File Server automatically uses five of the threads for its own
229 The maximum number of threads can differ in each release of AFS. Consult
230 the I<IBM AFS Release Notes> for the current release.
232 =item B<-spare> <I<number of spare blocks>>
234 Specifies the number of additional kilobytes an application can store in a
235 volume after the quota is exceeded. Provide a positive integer; a value of
236 C<0> prevents the volume from ever exceeding its quota. Do not combine
237 this argument with the B<-pctspare> argument.
239 =item B<-pctspare> <I<percentage spare>>
241 Specifies the amount by which the File Server allows a volume to exceed
242 its quota, as a percentage of the quota. Provide an integer between C<0>
243 and C<99>. A value of C<0> prevents the volume from ever exceeding its
244 quota. Do not combine this argument with the B<-spare> argument.
246 =item B<-b> <I<buffers>>
248 Sets the number of directory buffers. Provide a positive integer.
250 =item B<-l> <I<large vnodes>>
252 Sets the number of large vnodes available in memory for caching directory
253 elements. Provide a positive integer.
255 =item B<-s> <I<small nodes>>
257 Sets the number of small vnodes available in memory for caching file
258 elements. Provide a positive integer.
260 =item B<-vc> <I<volume cachesize>>
262 Sets the number of volumes the File Server can cache in memory. Provide a
265 =item B<-w> <I<call back wait interval>>
267 Sets the interval at which the daemon spawned by the File Server performs
268 its maintenance tasks. Do not use this argument; changing the default
269 value can cause unpredictable behavior.
271 =item B<-cb> <I<number of callbacks>>
273 Sets the number of callbacks the File Server can track. Provide a positive
278 Prints the following banner to F</dev/console> about every 10 minutes.
280 File Server is running at I<time>.
284 Prevents the File Server from breaking the callbacks that Cache Managers
285 hold on a volume that the File Server is reattaching after the volume was
286 offline (as a result of the B<vos restore> command, for example). Use of
287 this flag is strongly discouraged.
289 =item B<-implicit> <I<admin mode bits>>
291 Defines the set of permissions granted by default to the
292 system:administrators group on the ACL of every directory in a volume
293 stored on the file server machine. Provide one or more of the standard
294 permission letters (C<rlidwka>) and auxiliary permission letters
295 (C<ABCDEFGH>), or one of the shorthand notations for groups of permissions
296 (C<all>, C<none>, C<read>, and C<write>). To review the meaning of the
297 permissions, see the B<fs setacl> reference page.
299 =item B<-hr> <I<number of hours between refreshing the host cps>>
301 Specifies how often the File Server refreshes its knowledge of the
302 machines that belong to protection groups (refreshes the host CPSs for
303 machines). The File Server must update this information to enable users
304 from machines recently added to protection groups to access data for which
305 those machines now have the necessary ACL permissions.
307 =item B<-busyat> <I<< redirect clients when queue > n >>>
309 Defines the number of incoming RPCs that can be waiting for a response
310 from the File Server before the File Server returns the error code
311 C<VBUSY> to the Cache Manager that sent the latest RPC. In response, the
312 Cache Manager retransmits the RPC after a delay. This argument prevents
313 the accumulation of so many waiting RPCs that the File Server can never
314 process them all. Provide a positive integer. The default value is
317 =item B<-rxpck> <I<number of rx extra packets>>
319 Controls the number of Rx packets the File Server uses to store data for
320 incoming RPCs that it is currently handling, that are waiting for a
321 response, and for replies that are not yet complete. Provide a positive
326 Writes a trace of the File Server's operations on Rx packets to the file
327 F</usr/afs/logs/rx_dbg>.
331 Writes a trace of the File Server's operations on Rx events (such as
332 retransmissions) to the file F</usr/afs/logs/rx_dbg>.
334 =item F<-m> <I<min percentage spare in partition>>
336 Specifies the percentage of each AFS server partition that the AIX version
337 of the File Server creates as a reserve. Specify an integer value between
338 C<0> and C<30>; the default is 8%. A value of C<0> means that the
339 partition can become completely full, which can have serious negative
344 Prevents any portion of the fileserver binary from being paged (swapped)
345 out of memory on a file server machine running the IRIX operating system.
349 Sets values for many arguments in a manner suitable for a large file
350 server machine. Combine this flag with any option except the B<-S> flag;
351 omit both flags to set values suitable for a medium-sized file server
356 Sets values for many arguments in a manner suitable for a small file
357 server machine. Combine this flag with any option except the B<-L> flag;
358 omit both flags to set values suitable for a medium-sized file server
361 =item B<-k> <I<stack size>>
363 Sets the LWP stack size in units of 1 kilobyte. Do not use this argument,
364 and in particular do not specify a value less than the default of C<24>.
366 =item B<-realm> <I<Kerberos realm name>>
368 Defines the Kerberos realm name for the File Server to use. If this
369 argument is not provided, it uses the realm name corresponding to the cell
370 listed in the local F</usr/afs/etc/ThisCell> file.
372 =item B<-udpsize> <I<size of socket buffer in bytes>>
374 Sets the size of the UDP buffer, which is 64 KB by default. Provide a
375 positive integer, preferably larger than the default.
377 =item B<-enable_peer_stats>
379 Activates the collection of Rx statistics and allocates memory for their
380 storage. For each connection with a specific UDP port on another machine,
381 a separate record is kept for each type of RPC (FetchFile, GetStatus, and
382 so on) sent or received. To display or otherwise access the records, use
383 the Rx Monitoring API.
385 =item B<-enable_process_stats>
387 Activates the collection of Rx statistics and allocates memory for their
388 storage. A separate record is kept for each type of RPC (FetchFile,
389 GetStatus, and so on) sent or received, aggregated over all connections to
390 other machines. To display or otherwise access the records, use the Rx
395 Prints the online help for this command. All other valid options are
402 The following B<bos create> command creates an fs process on the file
403 server machine C<fs2.abc.com> that uses the large configuration size, and
404 allows volumes to exceed their quota by 10%. Type the command on a single
407 % bos create -server fs2.abc.com -instance fs -type fs \
408 -cmd "/usr/afs/bin/fileserver -pctspare 10 \
409 -L" /usr/afs/bin/volserver /usr/afs/bin/salvager
412 =head1 TROUBLESHOOTING
414 Sending process signals to the File Server Process can change its
415 behavior in the following ways:
417 Process Signal OS Result
418 ---------------------------------------------------------------------
420 File Server XCPU Unix Prints a list of client IP
423 File Server USR2 Windows Prints a list of client IP
426 File Server POLL HPUX Prints a list of client IP
429 Any server TSTP Any Increases Debug level by a power
430 of 5 -- 1,5,25,125, etc.
431 This has the same effect as the
432 -debug XXX command-line option.
434 Any Server HUP Any Resets Debug level to 0
436 File Server TERM Any Run minor instrumentation over
437 the list of descriptors.
439 Other Servers TERM Any Causes the process to quit.
441 File Server QUIT Any Causes the File Server to Quit.
442 Bos Server knows this.
444 The basic metric of whether an AFS file server is doing well is the number
445 of connections waiting for a thread,
446 which can be found by running the following command:
448 % rxdebug <server> | grep waiting_for | wc -l
450 Each line returned by C<rxdebug> that contains the text "waiting_for"
451 represents a connection that's waiting for a file server thread.
453 If the blocked connection count is ever above 0, the server is having
454 problems replying to clients in a timely fashion. If it gets above 10,
455 roughly, there will be noticable slowness by the user. The total number of
456 connections is a mostly irrelevant number that goes essentially
457 monotonically for as long as the server has been running and then goes back
458 down to zero when it's restarted.
460 The most common cause of blocked connections rising on a server is some
461 process somewhere performing an abnormal number of accesses to that server
462 and its volumes. If multiple servers have a blocked connection count, the
463 most likely explanation is that there is a volume replicated between those
464 servers that is absorbing an abnormally high access rate.
466 To get an access count on all the volumes on a server, run:
468 % vos listvol <server> -long
470 and save the output in a file. The results will look like a bunch of B<vos
471 examine> output for each volume on the server. Look for lines like:
473 40065 accesses in the past day (i.e., vnode references)
475 and look for volumes with an abnormally high number of accesses. Anything
476 over 10,000 is fairly high, but some volumes like root.cell and other
477 volumes close to the root of the cell will have that many hits routinely.
478 Anything over 100,000 is generally abnormally high. The count resets about
481 Another approach that can be used to narrow the possibilities for a
482 replicated volume, when multiple servers are having trouble, is to find all
483 replicated volumes for that server. Run:
485 % vos listvldb -server <server>
487 where <server> is one of the servers having problems to refresh the VLDB
490 % vos listvldb -server <server> -part <partition>
492 to get a list of all volumes on that server and partition, including every
493 other server with replicas.
495 Once the volume causing the problem has been identified, the best way to
496 deal with the problem is to move that volume to another server with a low
497 load or to stop any runaway programs that are accessing that volume
498 unnecessarily. Often the volume will be enough information to tell what's
501 If you still need additional information about who's hitting that server,
502 sometimes you can guess at that information from the failed callbacks in the
503 F<FileLog> log in F</var/log/afs> on the server, or from the output of:
505 % /usr/afsws/etc/rxdebug <server> -rxstats
507 but the best way is to turn on debugging output from the file server.
508 (Warning: This generates a lot of output into FileLog on the AFS server.)
509 To do this, log on to the AFS server, find the PID of the fileserver
514 where <pid> is the PID of the file server process. This will raise the
515 debugging level so that you'll start seeing what people are actually doing
516 on the server. You can do this up to three more times to get even more
517 output if needed. To reset the debugging level back to normal, use (The
518 following command will NOT terminate the file server):
522 The debugging setting on the File Server should be reset back to normal when
523 debugging is no longer needed. Otherwise, the AFS server may well fill its
524 disks with debugging output.
526 The lines of the debugging output that are most useful for debugging load
529 SAFS_FetchStatus, Fid = 2003828163.77154.82248, Host 171.64.15.76
530 SRXAFS_FetchData, Fid = 2003828163.77154.82248
532 (The example above is partly truncated to highlight the interesting
533 information). The Fid identifies the volume and inode within the volume;
534 the volume is the first long number. So, for example, this was:
536 % vos examine 2003828163
537 pubsw.matlab61 2003828163 RW 1040060 K On-line
538 afssvr5.Stanford.EDU /vicepa
539 RWrite 2003828163 ROnly 2003828164 Backup 2003828165
541 Creation Mon Aug 6 16:40:55 2001
542 Last Update Tue Jul 30 19:00:25 2002
543 86181 accesses in the past day (i.e., vnode references)
545 RWrite: 2003828163 ROnly: 2003828164 Backup: 2003828165
547 server afssvr5.Stanford.EDU partition /vicepa RW Site
548 server afssvr11.Stanford.EDU partition /vicepd RO Site
549 server afssvr5.Stanford.EDU partition /vicepa RO Site
551 and from the Host information one can tell what system is accessing that
554 Note that the output of L<vos_examine(1)> also includes the access count, so
555 once the problem has been identified, vos examine can be used to see if the
556 access count is still increasing. Also remember that you can run vos
557 examine on the read-only replica (e.g., pubsw.matlab61.readonly) to see the
558 access counts on the read-only replica on all of the servers that it's
561 =head1 PRIVILEGE REQUIRED
563 The issuer must be logged in as the superuser C<root> on a file server
564 machine to issue the command at a command shell prompt. It is conventional
565 instead to create and start the process by issuing the B<bos create>
581 IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.
583 This documentation is covered by the IBM Public License Version 1.0. It was
584 converted from HTML to POD by software written by Chas Williams and Russ
585 Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.