salvageserver - Initializes the Salvageserver component of the
dafs process
salvageserver [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>]
[-orphans (ignore | remove | attach)]
[-syslog]
[-syslogfacility <Syslog facility number to use>]
[-client] [-help]
In its typical mode of operation, the salvageserver is a
daemon process responsible for salvaging volumes. It is a component of the
"dafs" process type. In the conventional
configuration, its binary file is located in the /usr/lib/openafs
directory on a file server machine.
The Salvageserver daemon is responsible for scheduling and
executing volume salvage operations on behalf of client processes. The
fileserver acts as the primary salvageserver client: any failed volume
attach operation results in a salvageserver scheduling request. The
salvageserver also accepts periodic volume activity messages in order to
update its salvage request priority queue. Other clients of the
salvageserver daemon include the salvsync-debug utility, and the
salvageserver command itself by passing the -client flag.
The salvage operations performed on vice partition data are nearly
identical to those performed by the standalone Salvager command. The key
differences between the two commands are:
- The Salvageserver is a daemon process which runs concurrently with the
fileserver. In contrast, the Salvager is a stand-alone application which
is invoked when the fileserver and volserver are not running.
- The Salvageserver is incapable of performing whole partition salvage
operations; it operates at volume group granularity.
The Salvageserver 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 Salvageserver needs to create new inodes.
By default, multiple Salvageserver subprocesses run in parallel:
one for each volume group. By default, four concurrent salvage operations
are permitted. You may alter this default by providing a positive integer
value for the -parallel argument. The maximum permitted value is 32
concurrent salvageserver subprocesses.
By default, the salvageserver enables a heuristic which attempts
to stop disk head thrashing by concurrent salvageserver subprocesses.
Unfortunately, this heuristic significantly degrades performance in many
cases. In at least the following environments, passing the
"all" string to the -parallel
argument is strongly encouraged:
- On NAMEI fileservers
- When a vice partition is backed by multiple disks (e.g. RAID)
- When a vice partition is backed by SAN-attached storage, LVM, or some
other form of storage virtualization which would cause unix device id
numbers to be unpredictable.
The Salvageserver 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
Salvageserver terminates without completing the salvage operation (it always
removes the temporary files before exiting). Other Salvageserver
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 Salvageserver
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.
This command does not use the syntax conventions of the AFS
command suites. Provide the command name and all option names in full.
- [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
- This flag should be considered deprecated. Its primary purpose was to
disable forking and parallelization of the Salvager so that log messages
were not interleaved. Due to the manner in which
/var/log/openafs/SalsrvLog is written, log messages from
subprocesses are never interleaved; the entire log for a volume group
salvage is appended to the master log as one atomic transaction.
- -nowrite
- Brings all undamaged volumes online without attempting to salvage any
damaged volumes.
- -inodes
- Records in the /var/log/openafs/SalsrvLog file a list of all AFS
inodes that the Salvageserver 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/SalsrvLog 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 Salvageserver salvages a directory only if it is
flagged as corrupted.
- -blockreads
- Forces the Salvageserver 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
Salvageserver 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 Salvageserver 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 Salvageserver subprocess salvages the volume groups
sequentially. The disk partition heuristic (see above) based upon unix
device ids is enabled.
- The disk partition heuristic (see above) based upon unix device ids is
disabled.
- The string "all" followed immediately
(with no intervening space) by an integer from the range
1 to 32, to run the
specified number of Salvageserver subprocesses in parallel on volume
groups. The disk partition heuristic (see above) based upon unix device
ids is disabled.
If this argument is omitted, up to four Salvageserver subprocesses
run in parallel.
- -tmpdir <name
of dir to place tmp files>
- Names a local disk directory in which the Salvageserver places the
temporary files it creates during a salvage operation, instead of writing
them to the partition being salvaged (the default). If the Salvageserver
cannot write to the specified directory, it attempts to write to the
partition being salvaged.
- -orphans (ignore
| remove | attach)
- Controls how the Salvageserver 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/SalsrvLog 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/SalsrvLog 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 Salvageserver 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.
- -syslog
- Specifies that logging output should go to syslog instead of the log
file.
- -syslogfacility
<Syslog facility number to use>
- Specify to which facility log messages should be sent when -syslog
is given.
- -client
- Salvageserver runs in client Mode. The requested volume on the requested
partition will be scheduled for salvaging by the Salvageserver
daemon.
- -logfile
<log file>
- Sets the file to use for server logging. If logfile is not specified and
no other logging options are supplied, this will be
/var/log/openafs/SalsrvLog. Note that this option is intended for
debugging and testing purposes. Changing the location of the log file from
the command line may result in undesirable interactions with tools such as
bos.
- -help
- Prints the online help for this command. All other valid options are
ignored.
The following command instructs the Salvageserver to schedule the
salvage of the volume with volume ID 258347486 on /vicepg on the
local machine.
% /usr/lib/openafs/salvageserver -partition /vicepg -volumeid 258347486 -client
To issue the command at the shell prompt, the issuer must be
logged in as the local superuser
"root".
BosConfig(5), SalvageLog(5), salvager(8),
bos_create(8), bos_getlog(8), bos_salvage(8),
vos_move(1)
IBM Corporation 2000. <http://www.ibm.com/> All Rights
Reserved. Sine Nomine Associates 2008. 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. This
document was adapted from the Salvager POD documentation.