blkmapd - pNFS block layout mapping daemon
blkmapd [-h] [-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.
- -h
- Display usage message.
- -d
- Performs device discovery only then exits.
- -f
- Runs blkmapd in the foreground and sends output to
stderr (as opposed to syslogd)
The
blkmapd daemon recognizes the following value from the
[general] section of the
/etc/nfs.conf configuration file:
- pipefs-directory
- Tells blkmapd where to look for the rpc_pipefs
filesystem. The default value is /var/lib/nfs/rpc_pipefs.
nfs(5),
dmsetup(8),
nfs.conf(5)
RFC 5661 for the NFS version 4.1 specification.
RFC 5663 for the pNFS block layout specification.
Haiying Tang <
[email protected]>
Jim Rees <
[email protected]>