blkmapd - pNFS block layout mapping daemon


   blkmapd [-d] [-f]


   The  blkmapd  daemon  performs  device  discovery  and  mapping for the
   parallel NFS (pNFS) block layout client [RFC5663].

   The pNFS block layout protocol builds a complex storage hierarchy  from
   a  set  of  simple  volumes.   These  simple  volumes  are addressed by
   content, using a signature on the volume to  uniquely  name  each  one.
   The  daemon  locates  a  volume  by  examining each block device in the
   system for the given signature.

   The topology typically consists of a  hierarchy  of  volumes  built  by
   striping,  slicing,  and concatenating the simple volumes.  The blkmapd
   daemon uses the device-mapper driver to construct logical devices  that
   reflect the server topology, and passes these devices to the kernel for
   use by the pNFS block layout client.


   -d     Performs device discovery only then exits.

   -f     Runs blkmapd in the foreground and sends output  to  stderr  (as
          opposed to syslogd)


   nfs(5), dmsetup(8)

   RFC 5661 for the NFS version 4.1 specification.
   RFC 5663 for the pNFS block layout specification.


   Haiying Tang <>
   Jim Rees <>

                            11 August 2011                      blkmapd(8)


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