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PNFSDSFILE(8) FreeBSD System Manager's Manual PNFSDSFILE(8)
NAME
pnfsdsfile - display a pNFS data storage file's location(s) and/or modify
the "pnfsd.dsfile" extended attribute for them
SYNOPSIS
pnfsdsfile [-qz] [-s dshostname] [-c old-dshostname,new-dshostname]
[-m mirror_level] [-r dshostname] mdsfile
DESCRIPTION
The pnfsdsfile command displays the data storage file's location(s) for a
pNFS service and/or modifies the "pnfsd.dsfile" extended attribute on the
mdsfile. A pNFS service maintains a data storage file for each regular
file on the MetaData Server (MDS) on one or more of the Data Servers
(DS). If mirroring is enabled, the data storage file will be on more
that one of the DSs. Unless command options are specified, this command
displays the location(s) of the data storage file for the MDS file
mdsfile. It must be used on the MDS and the mdsfile must be a file on
the exported local file system and not an NFSv4.1 mount. This
information is stored in the "pnfsd.dsfile" extended attribute for this
mdsfile. The command line options allow the information in the
"pnfsd.dsfile" extended attribute to be changed.
The following options are available:
-q This option suppresses printing of the DS file's location(s).
-z This option specifies that the file handle field of the
pnfsd.dsfile extended attribute is to filled with all zero bits.
This forces the pNFS MDS to do a Lookup RPC against the DS to
acquire the file handle to update it. Normally this will only be
necessary after the DS file has been recovered from a backup,
causing the file handle to change.
-s dshostname
This option can be used with -z so that the zeroing out of the
file handle is only done if the DS server is the one specified by
this option.
-c old-dshostname,new-dshostname
This option allows a sysadmin to replace the host IP# for the DS
in the pnfsd.dsfile extended attribute. The old-hostname must
resolve to the IP# already in the pnfsd.dsfile extended attribute
or the replacement will not be done. If the old-dshostname
matches, then the IP# is replaced by the first AF_INET or
AF_INET6 address that getaddrinfo(3) returns for the new-
dshostname. Changing a DS server's host IP# should be avoided,
but this option will allow it to be changed, if the change is
unavoidable.
-m mirror_level
This option adds entrie(s) to the extended attributes with IP
address set to 0.0.0.0 to bring the number of entries up to
"mirror_level". It can be used by a system administrator to
prepare a file for mirroring via the pnfsdscopymr command with -r
option.
-r dshostname
when it is re-enabled. After being re-enabled, the command
pnfsdscopymr(1) with the "-r" option will be used to copy the
file's data to this repaired DS and then update the extended
attribute to use it.
A typical use of this will be within a find(1) for all regular
files in the MDS's exported tree.
For example, if the disabled DS is nfsv4-data3:
# cd <top-level-exported-directory-on-MDS>
# find . -type f -exec pnfsdsfile -q -r nfsv4-data3 {} \;
SEE ALSO
find(1), getaddrinfo(3), nfsv4(4), pnfs(4), nfsd(8), pnfsdscopymr(8),
pnfsdskill(8)
HISTORY
The pnfsdsfile command first appeared in FreeBSD 12.0.
FreeBSD 14.0-RELEASE-p11 June 30, 2018 FreeBSD 14.0-RELEASE-p11