fs, exsort - file server maintenance
help [ command ... ]
clean file [ bno [ addr ] ]
create path uid gid perm [lad]
date [[+-] seconds]
dump [ filesystem ]
flag flag [ channel ]
fstat [ files ]
newuser name [options]
stats [[-] flags...]
wormeject [ tunit ]
wormingest [ tunit ]
disk/exsort [-w] [file]
Except for exsort, these commands are available only on the console of
an fs(4) file server.
Help prints a `usage string' for the named commands, by default all
commands. Also, many commands print menus of their options if given
incorrect or incomplete parameters.
Allow disables permission checking and allows wstat. This may help in
initializing a file system. Use this with caution.
Arp has two subcommands: print prints the contents of the ARP cache and
flush flushes it.
Cfs changes the current file system, that is, the file tree to which
commands (check, clean, clri, create, cwcmd, dump, newuser, profile,
remove, and users) apply. The initial filesystem is main.
Check verifies the consistency of the current file system. With no
options it checks and reports the status. It suspends service while
running. Options are:
rdall Read every block in the file system (can take a long time).
Normally, check will stop short of the actual contents of a file
and just verify the block addresses.
tag Fix bad tags; each block has a tag that acts as a backwards
pointer for consistency checking.
ream Fix bad tags and also clear the contents of blocks that have bad
pfile Print every file name.
pdir Print every directory name.
free Rebuild the list of free blocks with all blocks that are not
referenced. This option is only useful on non-cache/WORM file
systems. If the filesystem was modified, the summary printed at
the conclusion of the check may not reflect the true state of
the freelist and may also print a list of missing blocks. These
missing blocks are actually on the free list and the true state
of the filesystem can be determined by running check with no
bad Each block address that is out of range or duplicate is cleared.
Note that only the second and subsequent use of a block is
cleared. Often the problems in a file system are caused by one
bad file that has a lot of garbage block addresses. In such a
case, it is wiser to use check to find the bad file (by number
of diagnostic messages) and then use clri to clear the addresses
in that file. After that, check can be used to reclaim the free
touch Cause every directory and indirect block not on the current WORM
disk to be advanced to the current WORM on the next dump. This
is a discredited idea to try to keep operating on the knee of
the cache working set. Buy more cache disk.
trim reduces the file system's fsize to fit the device containing the
file system. This is useful after copying a partially-full file
system into a slightly smaller device. Running check free
afterward will construct a new free list that contains no blocks
outside the new, smaller file system.
Clean prints the block numbers in file's directory entry (direct, indi‐
rect and doubly indirect) and checks the tags of the blocks cited. If
bno is supplied, the bno'th block number (using zero origin) is set to
addr (defaults to zero). Note that only the block numbers in the
directory entry itself are examined; clean does not recurse through
Clri clears the internal directory entry and abandons storage associ‐
ated with files. It ignores the usual rules for sanity, such as check‐
ing against removing a non-empty directory. A subsequent check free
will place the abandoned storage in the free list.
Cpu prints the CPU utilization and state of the processes in the file
server. If the name of a process type argument is given, then CPU uti‐
lization for only those processes is printed.
Create creates a file on the current file system. Uid and gid are
names or numbers from /adm/users. Perm is the low 9 bits of the per‐
mission mode of the file, in octal. An optional final l, a, or d cre‐
ates a locked file, append-only file, or directory.
Cwcmd controls the cached WORM file systems, specifically the current
file system. The subcommands are:
mvstate state1 state2 [platter]
States are none, dirty, dump, dump1, error, read, and write. A
mvstate dump1 dump will cause I/O errors in the last dump to be
retried. A mvstate dump1 write will cause I/O errors in the
last dump to be retried in reallocated slots in the next dump.
A mvstate read none will flush the cache associated with the
WORM. A mvstate dump write aborts the background process dump‐
ing to WORM; as a consequence it leaves holes in the dump file
system. Other uses are possible but arcane. The optional plat‐
ter limits affected blocks to those on that platter.
prchain [start] [back-flag]
Print the chain of superblocks for the directory containing the
roots of the dumped file systems, starting at block number start
(default 0) going forward (backwards if back-flag is supplied
and is non-zero).
searchtag [start] [tag] [blocks]
Reads the WORM device starting at block start and proceeding for
blocks blocks (default 1000) until it finds a block with numeric
Copy the block numbers, in native endian longwords, of blocks in
the read state to the file /adm/cache for use by disk/exsort.
If an argument is given, then that percent (most recently used)
of each cache bucket is copied.
Read /adm/cache and for every block there on WORM disk side
dskno (zero-origin), read the block from WORM to the cache. If
dskno is not supplied, all blocks in /adm/cache are read.
morecache dskno [count]
Read count blocks from the beginning of WORM disk side dskno to
the cache. If no count is given, read all of side dskno into
Suspend (0) or restart (1) the background dump process.
Verify that the superblock on the WORM is readable, ignoring the
blockcmp [wbno] [cbno]
Compares the WORM block wbno with the cache block cbno and
prints the first 10 differences, if any.
acct Prints how many times each user has caused the system to allo‐
cate new space on the WORM; the units are megabytes.
Clears the accounting records for acct.
Date prints the current date. It may be adjusted using +-seconds.
With no sign, it sets the date to the absolute number of seconds since
00:00 Jan 1, 1970 GMT; with a sign it trims the current time.
Disallow restores permission checking back to normal after a file sys‐
tem has been initialized.
Duallow sets permissions such that the named user can read and search
any directories. This is the permission necessary to do a du(1) com‐
mand anywhere in the file system to discover disk usage.
Dump starts a dump to WORM immediately for the named filesystem, or the
current filesystem if none is named. File service is suspended while
the cache is scanned; service resumes when the copy to WORM starts.
Files prints for every connection the number of allocated fids.
Fstat prints the current status of each named file, including uid, gid,
wuid (uid of the last user to modify the file), size, qid, and disk
Flag toggles flags, initially all off:
Print channels in who output.
arp Report ARP activity.
attach Report as connections are made to the file server.
chat (Very noisy.) Print all 9P messages to and from the server.
error Report 9P errors.
il Report IL errors.
route Report received RIP packets.
ro Report I/O on the WORM device.
sntp Report SNTP activity.
If given a second numeric channel argument, as reported by who, the
flag is altered only on that connection.
Halt does a sync and halts the machine, returning to the boot ROM.
Hangup clunks all the fids on the named channel, which has the same
format as in the output of the who command.
Newuser requires a name argument. With no options it adds user name,
with group leader name, to /adm/users and makes the directory /usr/name
owned by user and group name. The options are
? Print the entry for name.
: Add a group: add the name to /adm/users but don't create the
directory. By convention, groups are numbered starting from
10000, users from 0.
Rename existing user name to newname.
Change the leader of name to leader. If leader is missing,
remove the existing leader.
Add member to the member list of name.
Remove existing member from the member list of name.
After a successful newuser command the file server overwrites
/adm/users to reflect the internal state of the user table.
Noattach disables attach(5) messages, in particular for system mainte‐
nance. Previously attached connections are unaffected. Another noat‐
tach will enable normal behavior.
Passwd sets the machine's password and writes it in non-volatile RAM.
Printconf prints the system configuration information.
Profile 1 clears the profiling buffer and enables profiling; profile 0
stops profiling and writes the data to /adm/kprofdata for use by kprof
(see prof(1)). If a number is not specified, the profiling state tog‐
Remove removes files.
Route maintains an IP routing table. The subcommands are:
add dest gate [mask]
Add a static route from IP address dest using gateway gate with
an optional subnet mask.
Delete an entry from the routing table.
print Display the contents of the routing table.
ripon Enables the table to be filled from RIP packets.
ripoff Disables the table from being updated by RIP packets.
Sntp kick queries the SNTP server (see fsconfig(8)) and sets the time
with its response.
The stat commands are connected with a service or device identified by
the last character of the name: d, SCSI targets; e, Ethernet con‐
trollers; i, IDE/ATA targets; m, Marvell SATA targets; w, cached WORM.
The stata command prints overall statistics about the file system. The
stats command takes an optional argument identifying the characters of
stat commands to run. The option is remembered and becomes the default
for subsequent stats commands if it begins with a minus sign.
Sync writes dirty blocks in memory to the magnetic disk cache.
Time reports the time required to execute the command.
Trace with no options prints the set of queue-locks held by each
process in the file server. If things are quiescent, there should be
no output. With an argument number it prints a stack traceback of that
Users uses the contents of file (default /adm/users) to initialize the
file server's internal representation of the users structure. Incor‐
rectly formatted entries in file will be ignored. If file is explic‐
itly default, the system builds a minimal functional users table inter‐
nally; this can help recover from disasters. If the file cannot be
read, you must run
for the system to function. The default table looks like this:
Version reports when the file server was last compiled and last
Who reports, one per line, the names of users connected to the file
server and the status of their connections. The first number printed
on each line is the channel number of the connection. If users are
given the output selects connections owned by those users.
Wormeject moves the WORM disk in slot tunit of the first jukebox to the
Wormingest moves the WORM disk from the input shelf of the first juke‐
box to slot tunit.
Wormoffline takes drive of the first jukebox out of service; wormonline
puts it back in service.
Wormreset put discs back where the jukebox thinks they belong, and does
this for all jukeboxes.
When the file server boots, it prints the message
for config mode hit a key within 5 seconds
If a character is typed within 5 seconds of the message appearing, the
server will enter config mode. See fsconfig(8) for the commands avail‐
able in config mode. The system also enters config mode if, at boot
time, the non-volatile RAM does not appear to contain a valid configu‐
Exsort is a regular command to be run on a CPU server, not on the file
server console. It reads the named file (default /adm/cache) and sorts
the cache disk block numbers contained therein. It assumes the numbers
are 4-byte integers and guesses the endianness by looking at the data.
It then prints statistics about the cache. With option -w it writes
the sorted data back to file.
Ken Thompson, ``The Plan 9 File Server''.
The worm* commands should accept an argument identifying a jukebox.