HPUX and NFS

[Chris Fadrowski]

It has been requested by my DB group that i install and configure NFS on my Itanium HPUX 11.23v2 servers. I know very little about NFS. I was wondering if someone could briefly explain what it is and if this is a good idea to do.

In the past few years, NFS was something that other unix admins didn't like to work with and was just wondering if this is still the case.

[Pete Randall]

Basically, NFS is a client/server model for file sharing. You configure it using /etc/rc.config.d/nfsconf. If your HPUX server is going to share files with other systems, you need to configure it as an NFS server in the nfsconf file and also set up the file systems to be exported in /etc/exports. If your HPUX server is going to be accessing files from other servers, then you will configure it as a client in the nfsconf file. It can be both a client and a server, by the way.

You might want to start by taking a look at the man page for exportfs.


Pete

[Bharat Katkar · Accepted solution]

HI Chris,

1. Edit /etc/rc.config.d/nfsconf
NFS_CLIENT=1
NFS_SERVER=1

2. edit /etc/exports file. Add filesystems with desired permissions to be exported.
See "man exports" for more details.

3. # /sbin/init.d/nfs.core start
# /sbin/init.d/nfs.server start

4. # exportfs -a
This will export all your filesystems in /etc/exports file.

That's all for NFS server.

Similarly for client:

1. Edit /etc/rc.config.d/nfsconf
NFS_CLIENT=1
NFS_SERVER=0

2. # /sbin/init.d/nfs.core start
# /sbin/init.d/nfs.client start

3. # mount :

Hope that helps.
Regards,

[Chris Fadrowski]

does running NFS cause other architecture problems? Is it tricky to work with and require more administration to keep it reliable?

we have a SAN env and remember the engineer that installed it mention that if we were using NFS there is a different procedure for configuring disks etc...

[Steven E. Protter]

Shalom Chris,

The older the NFS, the harder it is to run.

Version three which is more or less current has troubles with locking files, uses random ports in a range, and creates hassles for admins.

Version 2 was UDP which made it terribly unreliable.

Version 4, which is new supposedly eliminates many of these issues.

You can use Samba to Integrate your system into a Windows domain and avoid some of the pitfalls of NFS.

SEP

[Bill Hassell]

Unlike Windows, filesystems are more tightly integrated in HP-UX and when they don't work correctly, a lot of things can hang up. On a production server, the result can be intolerable, as bad as a system crash since the fix is often a reboot. A 'real' disk is connected with a dedicated, relatively unshared electrical connection, but NFS is often transported over a network populated with other boxes with possible problems due that can cause network problems. Take A look at your network stats using lanadmin -- you may see a number of problems caused by long wires, dumb hubs (never use these on a production network), unpatched PCs, unpatched routers, etc. All of these (and more) can lead to intermittant problems.

The best choice for NFS is a dedicated (separate) LAN without any routers between the source machines. This is especially important if the NFS is going to transfer a lot of data for long periods of time. Be sure all the NFS patches are installed and be sure to get a copy of Dave Olker's book on NFS:

http://www.amazon.com/gp/product/0130428167/qid=1138802568/sr=1-1/ref=sr_1_1/103-6137958-9813419?s=books&v=glance&n=283155

Note that NFS is much slower than the slowest disk even with 100 Mbit links. A slow disk might transfer data at 20 Mbytes/sec, but you can expect about 50% throughput with a clean 100Mbiit link (which means 5 Mbytes/sec).

Since you have the latest OS (11.23v2), if you are up to date on patches, and the NFS is between other 11.23v2 servers on a dedicated LAN, you should be OK. I would never use NFS from a PC on a production system. SAMBA (CIFS) seems to have less problems with hangs but be sure the latest patches are in place on the PC. I would try NFS on your test boxes first.

[Arunvijai_4]

Hello,

NFS is still good in very big networks ~5000 servers of different OS like we use. We have had very little outage in last few years. It is very good and easy to manage.

-Arun

[Arunvijai_4]

Hi Again,

Here is a good guide to setting up NFS on 11iV2,

http://docs.hp.com/en/5991-1811/index.html

-Arun

[Steven E. Protter]

Dave Olker has an excellent book on NFS.

He is one of the world experts on it.

When you have 11i v2, install NFS 4 and use that.

Note that the Samba client runs on top of the NFS client anyway.

SEP

[Dave Olker]

Hi all,

Thanks for all the nice plugs on my book. :)

One point - HP-UX does not yet support NFS Version 4, even on 11i v2. We will be adding support for NFSv4 on 11i v3. So there is no way to install NFS Version 4 on an HP-UX system at this time.

One other white paper I'd suggest for your reading pleasure would be:

http://docs.hp.com/en/1435/NFSPerformanceTuninginHP-UX11.0and11iSystems.pdf

Regards,

Dave