topic Re: nfs in Operating System - Linux

nfs

Chakravarthi — Mon, 21 Oct 2002 04:11:51 GMT

Hi all..

How to find nfs version,,, which i'm using????

regards
chakri

Re: nfs

U.SivaKumar_2 — Mon, 21 Oct 2002 06:08:50 GMT

Hi,
Do this to find the version.

#/usr/sbin/rpc.nfsd --version

or this
#/usr/sbin/rpc.nfsd -v

These are differences between NFS V1 and NFS V2

Version 2 limits the client to 2 GB file size (32 bit offset) support; Version 3 supports larger files (up to 64 bit offsets), depending on the server
The Version 2 protocol limits the maximum data transfer size to 8K (8192 bytes); the Version 3 protocol will allow support of up to 64K. This maximum value is set to 8K on currently released Linux kernels, and is has been set to 32K in the latest experimental patches
The Version 2 protocol requires that each write request be posted to the server's disk before the server replies to the client; Version 3 requires only that the server returns the status of the data involved in the write request, and also provides a commit request which will not return until all data specified in the request has been posted to the server's disk

regards,
U.SivaKumar

Re: nfs

Chakravarthi — Mon, 21 Oct 2002 06:13:34 GMT

Hi,

Thanks for the information,,

I'm using Redhat 6.2 with 2.2.14 kernel,, and have NIS configure,, so user home directories are there in Storage, they get mounted onto the client through NFS, some times when i do cp or move operations i get input/output error,, is there any FIX for this,,

also it is possible to have NFS version 3 on 2.2 kernels,

regards
chakri

Re: nfs

U.SivaKumar_2 — Mon, 21 Oct 2002 06:40:32 GMT

Hi,

Ref:
NFS Version 2 has been around for quite some time now (at least since the 1.2 kernel series) however you will need a kernel version of at least 2.2.18 if you wish to do any of the following:

Mix Linux NFS with other operating systems' NFS

Use file locking reliably over NFS

Use NFS Version 3.

There are also patches available for kernel versions above 2.2.14 that provide the above functionality. Some of them can be downloaded from the Linux NFS homepage. If your kernel version is 2.2.14- 2.2.17 and you have the source code on hand, you can tell if these patches have been added because NFS Version 3 server support will be a configuration option. However, unless you have some particular reason to use an older kernel, you should upgrade because many bugs have been fixed along the way. Kernel 2.2.19 contains some additional locking improvements over 2.2.18.

Version 3 functionality will also require the nfs-utils package of at least version 0.1.6, and mount version 2.10m or newer. However because nfs-utils and mount are fully backwards compatible, and because newer versions have lots of security and bug fixes, there is no good reason not to install the newest nfs-utils and mount packages if you are beginning an NFS setup.

All 2.4 and higher kernels have full NFS Version 3 functionality.

In all cases, if you are building your own kernel, you will need to select NFS and NFS Version 3 support at compile time. Most (but not all) standard distributions come with kernels that support NFS version 3.

Handling files larger than 2 GB will require a 2.4x kernel and a 2.2.x version of glibc.

All kernels after 2.2.18 support NFS over TCP on the client side. As of this writing, server-side NFS over TCP only exists in a buggy form as an experimental option in the post-2.2.18 series; patches for 2.4 and 2.5 kernels have been introduced starting with 2.4.17 and 2.5.6. The patches are believed to be stable, though as of this writing they are relatively new and have not seen widespread use or integration into the mainstream 2.4 kernel.

Because so many of the above functionalities were introduced in kernel version 2.2.18, this document was written to be consistent with kernels above this version (including 2.4.x). If you have an older kernel, this document may not describe your NFS system correctly.

regards,
U.SivaKumar

Re: nfs

U.SivaKumar_2 — Mon, 21 Oct 2002 06:43:22 GMT

Hi,

Also check whether your nfs client's version is
matching with nfs server's version ( As said in my first reply )

To check the nfs client's version do this
#/usr/sbin/rpc.mountd --version

regards,
U.SivaKumar

Re: nfs

U.SivaKumar_2 — Mon, 21 Oct 2002 06:49:11 GMT

Hi,

Have a look at this link.

http://linuxselfhelp.com/HOWTO/NFS-HOWTO/performance.html

regards,
U.SivaKumar

Re: nfs

Chakravarthi — Mon, 21 Oct 2002 06:53:49 GMT

Hi,

I have to use 2.2.14, development specific reason,, so how to get rid of this input/output problem,,

Any suggestions for this

regards
chakri

Re: nfs

U.SivaKumar_2 — Mon, 21 Oct 2002 07:02:38 GMT

Hi,

In that case , please try following the recommendation below

http://nfs.sourceforge.net/nfs-howto/interop.html

you must mount a NFS directories in servers with rsize=1024,wsize=1024 options.

regards,
U.SivaKumar

Re: nfs

Chakravarthi — Mon, 21 Oct 2002 07:06:56 GMT

Hi,

FYI,

nfsstat -n gives the info about which nfs version you are using

regards
chakri

Re: nfs

U.SivaKumar_2 — Mon, 21 Oct 2002 07:30:45 GMT

Hi,
Thanls for FYI
Have my answers have helped you ?.

regards,
U.SivaKumar

Re: nfs

Chakravarthi — Mon, 21 Oct 2002 07:36:09 GMT

Hi,

I'm using automounter,, so i dont think i can specify any options in that ????

any help

regards
chakri

Re: nfs

U.SivaKumar_2 — Tue, 22 Oct 2002 05:26:36 GMT

Hi,

automounter is using automount daemon. It unmounts any mounted filesystem if it is idle for 5 minutes by default. Try Increasing the timeout to 20 min.

#automount -t 20

regards,
U.SivaKumar