NFS mounts but ls says "Input/output error"

I'm setting up a KnoppMyth box (R5F27, kernel 2.6.18) as a PVR, and
I'd like to give it access to all my MP3s, MPEGs, etc. on my main box
(Slack 10.2, kernel 2.6.13). I added an entry to /etc/exports on the
Slackware box:

/home/cjg 192.168.0.0/255.255.255.0(ro)

and rebooted; ps shows 8 copies of nfsd running. Over on the
KnoppMyth box, I created a mount point (/mnt/cjg) and typed:

mount 192.168.0.33:/home/cjg /mnt/cjg

The command was accepted - but when I try ls /mnt/cjg I get:

ls: reading directory /mnt/cjg: Input/output error

rpcinfo on the server (Slackwar) gives the following:

program vers proto port
100000 2 tcp 111 portmapper
100000 2 udp 111 portmapper
100011 1 udp 975 rquotad
100011 2 udp 975 rquotad
100011 1 tcp 978 rquotad
100011 2 tcp 978 rquotad
100003 2 udp 2049 nfs
100003 2 tcp 2049 nfs
100021 1 udp 32770 nlockmgr
100021 3 udp 32770 nlockmgr
100021 1 tcp 32769 nlockmgr
100021 3 tcp 32769 nlockmgr
100005 1 udp 985 mountd
100005 1 tcp 988 mountd
100005 2 udp 985 mountd
100005 2 tcp 988 mountd
100005 3 udp 985 mountd
100005 3 tcp 988 mountd
100024 1 udp 993 status
100024 1 tcp 996 status

while rpcinfo on the client (KnoppMyth) says:

program vers proto port
100000 2 tcp 111 portmapper
100000 2 udp 111 portmapper
100021 1 udp 32768 nlockmgr
100021 3 udp 32768 nlockmgr
100021 4 udp 32768 nlockmgr
100021 1 tcp 36516 nlockmgr
100021 3 tcp 36516 nlockmgr
100021 4 tcp 36516 nlockmgr

It looks as though I'm most of the way there. Any hints as to
what's going wrong?

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,--- Charlie Gibbs writes:

[...]

| rpcinfo on the server (Slackwar) gives the following:

| program vers proto port
| 100000 2 tcp 111 portmapper
| 100000 2 udp 111 portmapper
| 100011 1 udp 975 rquotad
| 100011 2 udp 975 rquotad
| 100011 1 tcp 978 rquotad
| 100011 2 tcp 978 rquotad
| 100003 2 udp 2049 nfs
| 100003 2 tcp 2049 nfs
| 100021 1 udp 32770 nlockmgr
| 100021 3 udp 32770 nlockmgr
| 100021 1 tcp 32769 nlockmgr
| 100021 3 tcp 32769 nlockmgr
| 100005 1 udp 985 mountd
| 100005 1 tcp 988 mountd
| 100005 2 udp 985 mountd
| 100005 2 tcp 988 mountd
| 100005 3 udp 985 mountd
| 100005 3 tcp 988 mountd
| 100024 1 udp 993 status
| 100024 1 tcp 996 status

You're not running NFS version 3, but running version 2.

| while rpcinfo on the client (KnoppMyth) says:

| program vers proto port
| 100000 2 tcp 111 portmapper
| 100000 2 udp 111 portmapper
| 100021 1 udp 32768 nlockmgr
| 100021 3 udp 32768 nlockmgr
| 100021 4 udp 32768 nlockmgr
| 100021 1 tcp 36516 nlockmgr
| 100021 3 tcp 36516 nlockmgr
| 100021 4 tcp 36516 nlockmgr

On your client side, you don't have support for NFS version 2.

HTH
- --
Ashish Shukla आशीष श�क�ल http://wahjava.wordpress.com/
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In article <(E-Mail Removed)>, (E-Mail Removed)
(Ashish Shukla) writes:

> Charlie Gibbs writes:
>
>> rpcinfo on the server (Slackwar) gives the following:
>>
>> program vers proto port
>> 100000 2 tcp 111 portmapper
>> 100000 2 udp 111 portmapper
>> 100011 1 udp 975 rquotad
>> 100011 2 udp 975 rquotad
>> 100011 1 tcp 978 rquotad
>> 100011 2 tcp 978 rquotad
>> 100003 2 udp 2049 nfs
>> 100003 2 tcp 2049 nfs
>> 100021 1 udp 32770 nlockmgr
>> 100021 3 udp 32770 nlockmgr
>> 100021 1 tcp 32769 nlockmgr
>> 100021 3 tcp 32769 nlockmgr
>> 100005 1 udp 985 mountd
>> 100005 1 tcp 988 mountd
>> 100005 2 udp 985 mountd
>> 100005 2 tcp 988 mountd
>> 100005 3 udp 985 mountd
>> 100005 3 tcp 988 mountd
>> 100024 1 udp 993 status
>> 100024 1 tcp 996 status
>
> You're not running NFS version 3, but running version 2.

I presume you're taking that from the "nfs" lines above?

>> while rpcinfo on the client (KnoppMyth) says:
>>
>> program vers proto port
>> 100000 2 tcp 111 portmapper
>> 100000 2 udp 111 portmapper
>> 100021 1 udp 32768 nlockmgr
>> 100021 3 udp 32768 nlockmgr
>> 100021 4 udp 32768 nlockmgr
>> 100021 1 tcp 36516 nlockmgr
>> 100021 3 tcp 36516 nlockmgr
>> 100021 4 tcp 36516 nlockmgr
>
> On your client side, you don't have support for NFS version 2.

Here I presume you're looking at the "nlockmgr" lines.

I've googled and checked man pages, but I can't find any
discussion of NFS version and compatibility issues. Are
my two boxes incompatible? (I hope not - it would be a
surprising and disappointing departure from the high degree
of compatibility I've come to take for granted from Linux,
and TCP/IP in general.)

Where do I go from here? Do I have to install another version of
Linux on one or both boxes? Do I have to find modules and rebuild
one or both kernels? Or are there some undocumented parameters I
have to tweak? (Charlie's First Law of Documentation states that
if you can't find it in the documentation, it isn't documented.)

--
/~\ (E-Mail Removed)lid (Charlie Gibbs)
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In article <(E-Mail Removed)>,
(E-Mail Removed)lid (Charlie Gibbs) writes:

Here's a strange followup on my NFS problem. I tried exporting
another directory, and it works! Here's my /etc/exports file:

# See exports(5) for a description.
# This file contains a list of all directories exported to other computers.
# It is used by rpc.nfsd and rpc.mountd.

/home/cjg 192.168.0.0/255.255.255.0(ro)
/bigspace 192.168.0.0/255.255.255.0(ro)

The first entry (/home/cjg) still doesn't work; mount comes up with
no errors but a subsequent ls does. If I mount the second directory
(/bigspace), though, everything goes OK, and I've successfully played
MP3s and MPEGs across the network.

/home/cjg is on my primary drive (reiserfs), while /bigspace takes
up all of a second drive (XFS).

Weird...

--
/~\ (E-Mail Removed)lid (Charlie Gibbs)
\ / I'm really at ac.dekanfrus if you read it the right way.
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"Charlie Gibbs" schrieb
>
> [NFS mounts but ls has input/output error]
>
What say the logs (/var/log/messages, I believe nfsd logs
also there)?

What are the permissions on the directories?


HTH
Martin

In article <47502178$0$3816$(E-Mail Removed)>, (E-Mail Removed)
(Martin Blume) writes:

> "Charlie Gibbs" schrieb
>
>> [NFS mounts but ls has input/output error]
>
> What say the logs (/var/log/messages, I believe nfsd logs
> also there)?

Each mount or umount generates an "rpc.mountd: authenticated
[un]mount request from <client IP addressort> for <directory
name>" message on the server, even on directories that give an
error when I try to do an ls.

> What are the permissions on the directories?

Duh! /home/cjg was 711, while /bigspace, another directory which
mounts and works just fine, is 755. A simple chmod did the trick.
Subsequently, directories within /home/cjg, which had permissions
of 700, were inaccessible until I changed them to 755, although I've
found that 744 (read permission) is enough for me to look inside.

It turns out that the user IDs I'm using on the client machine
don't match the user ID to which the server's directories and files
belong. Running as root on the client made no difference, but
I don't have no_root_squash specified so that's not surprising.

Many thanks for the tip - you've saved my hair. It seems odd,
though, that ls would return an obscure message like "Input/output
error" rather than some sort of "permission denied" message, which
would have immediately led me to the cause of the error...

--
/~\ (E-Mail Removed)lid (Charlie Gibbs)
\ / I'm really at ac.dekanfrus if you read it the right way.
X Top-posted messages will probably be ignored. See RFC1855.
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