SunOS 4.1.3 NFS problem with Solaris 2.6 server

Many thanks to the people who responded so quickly and succinctly to my

question about problems automounting from Sun OS 4.1.3_U1 to a Solaris 2.6

box. These respondents were:

bismark@alta.jpl.nasa.gov

david_thorburn-gundlach@groton.pfizer.com

kevin@uniq.com.au

putama@ect.enron.com

Simon-Bernard.Drolet@M3iSystems.QC.CA

Suggestions for solving the problem included troubleshooting the NFS network

traffic with snoop, reduce the size of the FDDI MTU to 1500 bytes, and make sure

the 2.6 server is sending NFS V2 over UDP (also via snoop). putama mailed the

Sunsolve NFS and automount FAQs, both of which I'd already read and put aside.

Per the NFS faq, I tried enabling fragmentation on the FDDI interface with

the following command:

        ndd -set /dev/ip ip_path_mtu_discovery 0

This didn't seem to make a difference. Snoop showed that the NFS server kept

attempting to retransmit a request for cookie information, which made me think

the NFSD was doing version 3 of NFS.

I ended up killing NFSD and MOUNTD and restarting them with nfsd -a 128 (up

from nfsd -a 64). After restarting NFS, the Sun OS boxes are able to automount

the Solaris 2.6 directories, and snoops appear normal.

My conclusion is that NFSD on the Solaris 2.6 box was not started properly,

and was trying to negotiate NFS version 3 with the Sun OS boxes.

Thanks again for your help,

Jim Dunbar

jdunbar@nyx.net

My original question appears below:

---------------------------------------------------------------------

Dear Sun Managers,

We recently installed Solaris 2.6 on an Ultra-2 Enterprise system with 128 MB

of memory and 150 MB of swap space. The primary purpose of this box is to

provide light NFS services for approximately 250 Solaris 2.5 and 2.5.1 clients.

There are also a few Sun OS 4.1.3_U1 servers that exist in the environment as

"legacy" boxes that will be phased out over the next year. Automounting is the

primary method of attaching to the NFS server.

The NFS server is equipped with a FDDI interface through which the clients

will attach for file services. The clients are attached to 10 mb ethernet

which is switched onto the FDDI ring as needed.

So far, all is well with the Solaris 2.5 and 2.5.1 NFS clients. They see the

server's shared disks and have no problems accessing the data. The Sun OS

boxes are another matter. The automounted disks are shown as mounted, but

when attempting to access the NFS disks, the Sun OS boxes report errors such

as "NFS read failed for server <servername>: RPC: Timed out." These errors

are reported when the NFS server disks are soft-mounted. When changing the

mount type to hard, the Sun OS boxes report that "NFS server <servername> not

responding. Still trying," and never come back to the UNIX prompt.

My question is: Does anyone know of any Solaris 2.6 changes to NFS that would

prevent Sun OS automounts from working correctly? Note that Sun OS standard

mounts work fine. Note also that we have several 2.5.1 servers to which the

Sun OS boxes are doing automounts without a problem.

Thanks in advance for any help you can give me. I'll be sure to summarize.

Jim Dunbar

jdunbar@nyx.net

[4714 byte] By [CodeProf.com] at [2007-12-25 11:51:00]