1blkmapd(8)                  System Manager's Manual                 blkmapd(8)
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NAME

6       blkmapd - pNFS block layout mapping daemon
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SYNOPSIS

9       blkmapd [-h] [-d] [-f]
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DESCRIPTION

12       The blkmapd daemon performs device discovery and mapping for the paral‐
13       lel NFS (pNFS) block layout client [RFC5663].
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15       The pNFS block layout protocol builds a complex storage hierarchy  from
16       a  set  of  simple volumes.  These simple volumes are addressed by con‐
17       tent, using a signature on the volume to uniquely name each  one.   The
18       daemon  locates  a  volume by examining each block device in the system
19       for the given signature.
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21       The topology typically consists of a  hierarchy  of  volumes  built  by
22       striping,  slicing,  and concatenating the simple volumes.  The blkmapd
23       daemon uses the device-mapper driver to construct logical devices  that
24       reflect the server topology, and passes these devices to the kernel for
25       use by the pNFS block layout client.
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OPTIONS

28       -h     Display usage message.
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30       -d     Performs device discovery only then exits.
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32       -f     Runs blkmapd in the foreground and sends output  to  stderr  (as
33              opposed to syslogd)
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CONFIGURATION FILE

36       The  blkmapd  daemon  recognizes the following value from the [general]
37       section of the /etc/nfs.conf configuration file:
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39       pipefs-directory
40              Tells blkmapd where to look for the rpc_pipefs filesystem.   The
41              default value is /var/lib/nfs/rpc_pipefs.
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SEE ALSO

44       nfs(5), dmsetup(8), nfs.conf(5)
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46       RFC 5661 for the NFS version 4.1 specification.
47       RFC 5663 for the pNFS block layout specification.
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AUTHORS

50       Haiying Tang <Tang_Haiying@emc.com>
51       Jim Rees <rees@umich.edu>
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55                                11 August 2011                      blkmapd(8)