CentOS NFS Problems

Posted on 2010-09-04
Last Modified: 2012-05-10

I'm trying to use an CentOS 5.5 with two 2TB stand alone disks as a NFS Server.

When i try to mount an exported partition, i receive the follow error in /etc/messages:

Sep  4 16:21:59 storage mountd[3170]: authenticated mount request from for /backup/ded01.bruno-fernandes (/backup/ded01.bruno-fernandes)
Sep  4 16:22:01 storage kernel: RPC: bad TCP reclen 0x00100098 (large)
Sep  4 16:22:34 storage last message repeated 224 times
Sep  4 16:23:35 storage last message repeated 391 times
Sep  4 16:24:36 storage last message repeated 326 times

At the client side, the command not end. (Obs: on client side has no Firewall rules)

root@ded [~]# mount -t nfs /backup  

There are some another until information of the server:

[root@storage ~]# rpcinfo -p
   program vers proto   port
    100000    2   tcp    111  portmapper
    100000    2   udp    111  portmapper
    100024    1   udp    799  status
    100024    1   tcp    802  status
    100011    1   udp    788  rquotad
    100011    2   udp    788  rquotad
    100011    1   tcp    791  rquotad
    100011    2   tcp    791  rquotad
    100003    2   udp   2049  nfs
    100003    3   udp   2049  nfs
    100003    4   udp   2049  nfs
    100021    1   udp  51853  nlockmgr
    100021    3   udp  51853  nlockmgr
    100021    4   udp  51853  nlockmgr
    100003    2   tcp   2049  nfs
    100003    3   tcp   2049  nfs
    100003    4   tcp   2049  nfs
    100021    1   tcp  33205  nlockmgr
    100021    3   tcp  33205  nlockmgr
    100021    4   tcp  33205  nlockmgr
    100005    1   udp    802  mountd
    100005    1   tcp    805  mountd
    100005    2   udp    802  mountd
    100005    2   tcp    805  mountd
    100005    3   udp    802  mountd
    100005    3   tcp    805  mountd
[root@storage ~]#

The contents of /etc/exports:

[root@storage ~]# showmount --exports
Export list for
[root@storage ~]#

[root@storage ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              19G  1.4G   17G   8% /
/dev/sda5             1.8T  196M  1.7T   1% /backup
/dev/sdb1             1.8T  123G  1.6T   8% /backup2
/dev/sda1             487M   22M  440M   5% /boot
tmpfs                1013M     0 1013M   0% /dev/shm
[root@storage ~]#

[root@storage ~]# uname -a
Linux 2.6.18-194.11.3.el5 #1 SMP Mon Aug 30 16:23:24 EDT 2010 i686 i686 i386 GNU/Linux
[root@storage ~]#
Question by:maxihost
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Expert Comment

ID: 33604761
Might be a problem with Jumbo Frames

try turning off jumbo frames and testing if the problem goes away


Expert Comment

ID: 33604836
You are using a public ip address. Usually NFS is on a private address. The lock ports are now randomly selected. You must make sure machines that access the NFS volume are using the same ports. I can't explain exactly how to do this in a post here, because I don't have enough space. There are plenty of tutorials available online.  

Accepted Solution

atech1 earned 500 total points
ID: 33605677
For troubleshooting purposes, try using NFS over UDP.

on the client:

            mount -t nfs -o udp nfsserver:/export/path /mountpoint

Note that the initial rpc portmap handshake is done via tcp port 111, but after that all
data transmission is done via UDP.
Remember that the there is no data check, retransmission, etc, with the UDP protocol.

Have a look at "man nfs"

proto=n        Mount the NFS filesystem using a specific network protocol instead of the default  TCP  protocol.
                     Valid protocol types are udp and tcp.

perhaps this might be informative:


Expert Comment

ID: 33605680
CORRECTION to my previous post.

mount -t nfs proto=udp nfsserver:/export/path /mountpoint


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