linux-stable/Documentation/filesystems/nfs
Sachin Bhamare 18d98f6c04 pnfs-obj: autologin: Add support for protocol autologin
The pnfs-objects protocol mandates that we autologin into devices not
present in the system, according to information specified in the
get_device_info returned from the server.

The Protocol specifies two login hints.
1. An IP address:port combination
2. A string URI which is constructed as a URL with a protocol prefix
   followed by :// and a string as address. For each  protocol prefix
   the string-address format might be different.

We only support the second option. The first option is just redundant
to the second one.
NOTE: The Kernel part of autologin does not parse the URI string. It
just channels it to a user-mode script. So any new login protocols should
only update the user-mode script which is a part of the nfs-utils package,
but the Kernel need not change.

We implement the autologin by using the call_usermodehelper() API.
(Thanks to Steve Dickson <steved@redhat.com> for pointing it out)
So there is no running daemon needed, and/or special setup.

We Add the osd_login_prog Kernel module parameters which defaults to:
	/sbin/osd_login

Kernel try's to upcall the program specified in osd_login_prog. If the file is
not found or the execution fails Kernel will disable any farther upcalls, by
zeroing out  osd_login_prog, Until Admin re-enables it by setting the
osd_login_prog parameter to a proper program.

Also add text about the osd_login program command line API to:
	Documentation/filesystems/nfs/pnfs.txt
and documentation of the new  osd_login_prog  module parameter to:
	Documentation/kernel-parameters.txt

TODO: Add timeout option in the case osd_login program gets
              stuck

Signed-off-by: Sachin Bhamare <sbhamare@panasas.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21 09:31:47 -04:00
..
00-INDEX NFSD: Added fault injection documentation 2011-11-07 21:10:47 -05:00
Exporting Documentation: Exporting: update description of d_splice_alias 2011-07-26 12:57:09 -04:00
fault_injection.txt NFSD: Added fault injection documentation 2011-11-07 21:10:47 -05:00
idmapper.txt NFS: Update idmapper documentation 2012-02-06 18:48:01 -05:00
knfsd-stats.txt
nfs-rdma.txt
nfs.txt
nfs41-server.txt nfsd4: update nfsv4.1 implementation notes 2011-07-18 18:41:33 -04:00
nfsroot.txt doc: fix wrong arch/i386 references 2011-06-13 13:43:05 +02:00
pnfs.txt pnfs-obj: autologin: Add support for protocol autologin 2012-03-21 09:31:47 -04:00
rpc-cache.txt Documentation/: it's -> its where appropriate 2010-04-23 02:09:52 +02:00