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| author | Daniel W. S. Almeida <dwlsalmeida@gmail.com> | 2020-01-11 02:24:29 +0300 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2020-01-16 22:43:05 +0300 |
| commit | 26f6225fa53dc4ad26b9d9d712c0f55a92eb2c23 (patch) | |
| tree | f9d2bb1e7ddec06195e4dd09dd3b1ffc9933c862 /Documentation/admin-guide/nfs | |
| parent | fbdcd0b8e56492dd85bd8d08f15a14334bb59259 (diff) | |
| download | linux-26f6225fa53dc4ad26b9d9d712c0f55a92eb2c23.tar.xz | |
Documentation: nfs: convert pnfs-block-server to ReST
Convert pnfs-block-server.txt to ReST and move it to admin-guide.
Content remains mostly unchanged.
Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/c06903760e690c16d9df92f5e75f80381d6326d8.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/admin-guide/nfs')
| -rw-r--r-- | Documentation/admin-guide/nfs/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/admin-guide/nfs/pnfs-block-server.rst | 42 |
2 files changed, 43 insertions, 0 deletions
diff --git a/Documentation/admin-guide/nfs/index.rst b/Documentation/admin-guide/nfs/index.rst index 8376d5225fc2..365f42a611a4 100644 --- a/Documentation/admin-guide/nfs/index.rst +++ b/Documentation/admin-guide/nfs/index.rst @@ -10,3 +10,4 @@ NFS nfs-rdma nfsd-admin-interfaces nfs-idmapper + pnfs-block-server diff --git a/Documentation/admin-guide/nfs/pnfs-block-server.rst b/Documentation/admin-guide/nfs/pnfs-block-server.rst new file mode 100644 index 000000000000..b00a2e705cc4 --- /dev/null +++ b/Documentation/admin-guide/nfs/pnfs-block-server.rst @@ -0,0 +1,42 @@ +=================================== +pNFS block layout server user guide +=================================== + +The Linux NFS server now supports the pNFS block layout extension. In this +case the NFS server acts as Metadata Server (MDS) for pNFS, which in addition +to handling all the metadata access to the NFS export also hands out layouts +to the clients to directly access the underlying block devices that are +shared with the client. + +To use pNFS block layouts with with the Linux NFS server the exported file +system needs to support the pNFS block layouts (currently just XFS), and the +file system must sit on shared storage (typically iSCSI) that is accessible +to the clients in addition to the MDS. As of now the file system needs to +sit directly on the exported volume, striping or concatenation of +volumes on the MDS and clients is not supported yet. + +On the server, pNFS block volume support is automatically if the file system +support it. On the client make sure the kernel has the CONFIG_PNFS_BLOCK +option enabled, the blkmapd daemon from nfs-utils is running, and the +file system is mounted using the NFSv4.1 protocol version (mount -o vers=4.1). + +If the nfsd server needs to fence a non-responding client it calls +/sbin/nfsd-recall-failed with the first argument set to the IP address of +the client, and the second argument set to the device node without the /dev +prefix for the file system to be fenced. Below is an example file that shows +how to translate the device into a serial number from SCSI EVPD 0x80:: + + cat > /sbin/nfsd-recall-failed << EOF + +.. code-block:: sh + + #!/bin/sh + + CLIENT="$1" + DEV="/dev/$2" + EVPD=`sg_inq --page=0x80 ${DEV} | \ + grep "Unit serial number:" | \ + awk -F ': ' '{print $2}'` + + echo "fencing client ${CLIENT} serial ${EVPD}" >> /var/log/pnfsd-fence.log + EOF |