getting input/output error from NFS client on RHEL5

Question

I have two RHEL5 boxes on a private network together (192.168.2.0/24) and I am trying to export a file system from one to the other but I keep getting the following error:

mount.nfs: Input/output error

on the client side I see this output:

mount: trying 192.168.2.101 prog 100003 vers 3 prot tcp port 2049
mount: trying 192.168.2.101 prog 100005 vers 3 prot tcp port 960

and on the server side I see this:

Sep 20 14:14:32 omicron mountd[18739]: authenticated mount request from 192.168.2.87:635 for /srv/nfs/web (/srv/nfs/web)

but that's all. I opened up iptables so that the whole 192.168.2.0/24 network is allowed to communicate freely but the public side is locked down to 22,80 etc....

any ideas?

Solution 1

Make sure portmapper is running

On centos

chkconfig --list | grep portmap

To start it on centos and set it to start at boot

service portmap start
chkconfig portmap on

Solution 2

For a similar problem, I have added to the syntax of the mount command the following options "-o nolock, udp."

mount -o nolock,udp 192.168.4.11:/var/nfs /mnt/nfs/

Apparently this problem when the service nfslook is not 'started' successfully.

Solution 3

I had a similar problem, please have a look at this link.
And this one.

Basically you have to open much more ports.

Comments

[Rilindo]

That should be in the comments, not in the answers.