salvager(8)
NAME
salvager - Initializes the Salvager component of the fs process
SYNOPSIS
salvager
[initcmd] [-partition <name of partition to salvage>]
[-volumeid <volume id to salvage>] [-debug] [-nowrite]
[-inodes] [-force] [-oktozap] [-rootinodes]
[-salvagedirs] [-blockreads]
[-parallel <# of max parallel partition salvaging>]
[-tmpdir <name of dir to place tmp files>]
[-showlog] [-showsuid] [-showmounts]
[-orphans (ignore | remove | attach)] [-help]
DESCRIPTION
The salvager command initializes the Salvager component of the "fs"
process. In the conventional configuration, its binary file is located
in the /usr/lib/openafs directory on a file server machine.
The Salvager restores internal consistency to corrupted read/write
volumes on the local file server machine where possible. For read-only
or backup volumes, it inspects only the volume header:
* If the volume header is corrupted, the Salvager removes the volume
completely and records the removal in its log file,
/var/log/openafs/SalvageLog. Issue the vos release or vos backup
command to create the read-only or backup volume again.
* If the volume header is intact, the Salvager skips the volume (does
not check for corruption in the contents). However, if the File
Server notices corruption as it initializes, it sometimes refuses
to attach the volume or bring it online. In this case, it is
simplest to remove the volume by issuing the vos remove or vos zap
command. Then issue the vos release or vos backup command to create
it again.
Unlike other server process initialization commands, the Salvager
command is designed to be issued at the command shell prompt, as well
as being placed into a file server machine's /etc/openafs/BosConfig
file with the bos create command. It is also possible to invoke the
Salvager remotely by issuing the bos salvage command.
Combine the command's options as indicated to salvage different numbers
of read/write volumes:
* To salvage all volumes on the file server machine, provide no
arguments. No volumes on the machine are accessible to Cache
Managers during the salvage, because the BOS Server stops the File
Server and Volume Server processes while the Salvager runs.
* To salvage all of the volumes on one partition, provide the
-partition argument. As for a salvage of all volumes on the
machine, no volumes on the machine are accessible to Cache Managers
during the salvage operation.
* To salvage only one volume, combine the -partition and -volumeid
arguments. Only that volume is inaccessible to Cache Managers,
because the BOS Server does not shutdown the File Server and Volume
Server processes.
The Salvager normally salvages only those read/write volumes that are
marked as having been active when a crash occurred. To have it salvage
all relevant read/write volumes, add the -force flag.
The Salvager normally creates new inodes as it repairs damage. If the
partition is so full that there is no room for new inodes, use the
-nowrite argument to bringing undamaged volumes online without
attempting to salvage damaged volumes. Then use the vos move command to
move one or more of the undamaged volumes to other partitions, freeing
up the space that the Salvager needs to create new inodes.
By default, multiple Salvager subprocesses run in parallel: one for
each partition up to four, and four subprocesses for four or more
partitions. To increase or decrease the number of subprocesses running
in parallel, provide a positive integer value for the -parallel
argument.
If there is more than one server partition on a physical disk, the
Salvager by default salvages them serially to avoid the inefficiency of
constantly moving the disk head from one partition to another. However,
this strategy is often not ideal if the partitions are configured as
logical volumes that span multiple disks. To force the Salvager to
salvage logical volumes in parallel as if they were on separate disks,
provide the string "all" as the value for the -parallel argument.
To set both parameters at the same time, append the number of Salvager
processes to the string "all". For example, "-parallel all5" treats
each partition as a separate disk and runs five Salvager processes,
thus salvaging five partitions at a time.
The Salvager creates temporary files as it runs, by default writing
them to the partition it is salvaging. The number of files can be quite
large, and if the partition is too full to accommodate them, the
Salvager terminates without completing the salvage operation (it always
removes the temporary files before exiting). Other Salvager
subprocesses running at the same time continue until they finish
salvaging all other partitions where there is enough disk space for
temporary files. To complete the interrupted salvage, reissue the
command against the appropriate partitions, adding the -tmpdir argument
to redirect the temporary files to a local disk directory that has
enough space.
The -orphans argument controls how the Salvager handles orphaned files
and directories that it finds on server partitions it is salvaging. An
orphaned element is completely inaccessible because it is not
referenced by the vnode of any directory that can act as its parent (is
higher in the filespace). Orphaned objects occupy space on the server
partition, but do not count against the volume's quota.
To generate a list of all mount points that reside in one or more
volumes, rather than actually salvaging them, include the -showmounts
flag.
This command does not use the syntax conventions of the AFS command
suites. Provide the command name and all option names in full.
OPTIONS
[initcmd]
Accommodates the command's use of the AFS command parser, and is
optional.
-partition <name of partition to salvage>
Specifies the name of the partition to salvage. Specify the full
partition name using the form /vicepx or /vicepxx. Omit this
argument to salvage every partition on the file server machine.
-volumeid <volume id to salvage>
Specifies the volume ID of a specific read/write volume to salvage.
The -partition argument must be provided along with this one and
specify the volume's actual site.
-debug
Allows only one Salvager subprocess to run at a time, regardless of
the setting of the -parallel option. Include it when running the
Salvager in a debugger to make the trace easier to interpret.
-nowrite
Brings all undamaged volumes online without attempting to salvage
any damaged volumes.
-inodes
Records in the /var/log/openafs/SalvageLog file a list of all AFS
inodes that the Salvager modified.
-force
Inspects all volumes for corruption, not just those that are marked
as having been active when a crash occurred.
-oktozap
Removes a volume that is so damaged that even issuing the vos zap
command with the -force flag is ineffective. Combine it with the
-partition and -volumeid arguments to identify the volume to
remove. Using this flag will destroy data that cannot be read, so
use only with caution and when you're certain that nothing in that
volume is still needed.
-rootinodes
Records in the /var/log/openafs/SalvageLog file a list of all AFS
inodes owned by the local superuser "root".
-salvagedirs
Salvages entire directory structures, even if they do not appear to
be damaged. By default, the Salvager salvages a directory only if
it is flagged as corrupted.
-blockreads
Forces the Salvager to read a partition one disk block (512 bytes)
at a time and to skip any blocks that are too badly damaged to be
salvaged. This allows it to salvage as many volumes as possible.
By default, the Salvager reads large disk blocks, which can cause
it to exit prematurely if it encounters disk errors. Use this flag
if the partition to be salvaged has disk errors.
-parallel <# of max parallel partition salvaging>
Specifies the maximum number of Salvager subprocesses to run in
parallel. Provide one of three values:
* An integer from the range 1 to 32. A value of 1 means that a
single Salvager process salvages the partitions sequentially.
* The string "all" to run up to four Salvager subprocesses in
parallel on partitions formatted as logical volumes that span
multiple physical disks. Use this value only with such logical
volumes.
* The string "all" followed immediately (with no intervening
space) by an integer from the range 1 to 32, to run the
specified number of Salvager subprocesses in parallel on
partitions formatted as logical volumes. Use this value only
with such logical volumes.
The BOS Server never starts more Salvager subprocesses than there
are partitions, and always starts only one process to salvage a
single volume. If this argument is omitted, up to four Salvager
subprocesses run in parallel but partitions on the same device are
salvaged serially.
-tmpdir <name of dir to place tmp files>
Names a local disk directory in which the Salvager places the
temporary files it creates during a salvage operation, instead of
writing them to the partition being salvaged (the default). If the
Salvager cannot write to the specified directory, it attempts to
write to the partition being salvaged.
-showlog
Displays on the standard output stream all log data that is being
written to the /var/log/openafs/SalvageLog file.
-showsuid
Displays a list of the pathnames for all files that have the setuid
or setgid mode bit set.
-showmounts
Records in the /var/log/openafs/SalvageLog file all mount points
found in each volume. The Salvager does not repair corruption in
the volumes, if any exists.
-orphans (ignore | remove | attach)
Controls how the Salvager handles orphaned files and directories.
Choose one of the following three values:
ignore
Leaves the orphaned objects on the disk, but prints a message
to the /var/log/openafs/SalvageLog file reporting how many
orphans were found and the approximate number of kilobytes they
are consuming. This is the default if the -orphans argument is
omitted.
remove
Removes the orphaned objects, and prints a message to the
/var/log/openafs/SalvageLog file reporting how many orphans
were removed and the approximate number of kilobytes they were
consuming.
attach
Attaches the orphaned objects by creating a reference to them
in the vnode of the volume's root directory. Since each
object's actual name is now lost, the Salvager assigns each one
a name of the following form:
"__ORPHANFILE__.index" for files.
"__ORPHANDIR__.index" for directories.
where index is a two-digit number that uniquely identifies each
object. The orphans are charged against the volume's quota and
appear in the output of the ls command issued against the
volume's root directory.
-help
Prints the online help for this command. All other valid options
are ignored.
EXAMPLES
The following command instructs the Salvager to attempt to salvage the
volume with volume ID 258347486 on /vicepg on the local machine.
% /usr/lib/openafs/salvager -partition /vicepg -volumeid 258347486
PRIVILEGE REQUIRED
To issue the command at the shell prompt, the issuer must be logged in as the local superuser "root".
SEE ALSO
BosConfig(5), SalvageLog(5), bos_create(8), bos_getlog(8), bos_salvage(8), vos_move(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.
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