Unable to mount nfs

samkhan83 · 08-13-2012, 05:09 AM

Hi Gurus,

I am using 2.6.32-71.el6.x86_64. I have a volume mounted via NFS on my server. This volume actually resides on my storage (NetApp).

I have two problems.

1) When I create a directory on that partition as root, the owner and group defaults to nfsnobody. But when I create a directory as any other user except root, the owner and group is of that same user through which I created the directory.

2) When I try to make this server as NFS server, by sharing the volume that is already mounted as NFS, i get an error as below

[root@portaltest1 linxnfs]# exportfs -a
exportfs: Warning: /linxnfs/shared does not support NFS export.
[root@portaltest1 linxnfs]#

Can anybody help me in this regard?

Thank a lot in advance.

maniannam · 08-13-2012, 09:44 AM

Hello,

what is the FileSystem Type?

Regards,
maniannam

samkhan83 · 08-13-2012, 01:40 PM

Hello,

Filesystem is NFS.

Regards.

suicidaleggroll · 08-13-2012, 01:47 PM

NFS is not a filesystem, it's a network protocol similar to CIFS. Maniannam is asking what the actual filesystem is, such as ntfs, ext3, etc.

#1 is normal behavior, and is caused by rootsquash on the NFS share. This means that "root" on any remote machine does not have the same permissions as "root" on the local machine, so that there is only one "root" with true global permissions on that filesystem...the one on the actual machine on which that filesystem resides.

#2 - I've never tried to re-share a NFS mount, and I don't really see the benefit. Why not just have the clients mount the original share directly instead of doubling your network overhead by daisy chaining the mount?

samkhan83 · 08-13-2012, 01:52 PM

Very sorry to say but strangely the FS in NFS stands for file system. That makes it a filesystem doesn't it?

samkhan83 · 08-13-2012, 01:54 PM

To further prove my point:

Code:

Filesystem    Type   1K-blocks      Used Available Use% Mounted on
/dev/mapper/vg_portaltest1-lv_root
              ext4    15227752   8161956   6292268  57% /
tmpfs        tmpfs    15473904       624  15473280   1% /dev/shm
/dev/sda1     ext4      495844     36406    433838   8% /boot
udntap-n1-sata:/vol/portaltest1_211/qt1
               nfs    54525952  14737216  39788736  28% /linxnfs

suicidaleggroll · 08-13-2012, 01:54 PM

You can't always take the definition of an acronym at face value.

NFS is a network protocol. Just like RAID stands for redundant array of independent disks...however RAID0, despite being a legitimate RAID implementation, has no redundancy.

samkhan83 · 08-13-2012, 01:58 PM

Thanks suicidaleggroll, always nice to learn from people like yourself.

Can you tell me how can I check the filesystem on this partition that is shared by my storage (NetApp) and mounted on my server via NFS protocol.

According to me i am trying df -T

Regards

suicidaleggroll · 08-13-2012, 01:59 PM

Easiest way is to log into the server (NetApp) and run df -T there.

For example, on my local machine:

Code:

[user@client ~]$ df -T | grep raid
server:/raid   nfs     37T  326G   37T   1% /server/raid

But on the server:

Code:

[user@server ~]$ df -T | grep raid
/dev/sdc1      xfs     37T  326G   37T   1% /raid

So it's actually an XFS filesystem. NFS is just the protocol that allows me to remotely access it on my client machine.

samkhan83 · 08-13-2012, 02:11 PM

NetApp is my storage server. I dont think df -T will work there.

Code:

udntap-n2-sas> df -T
df: Invalid option - T
usage: df [ -i | -r | -S | -s | -x ] [ -h | -k | -m | -g | -t ] [ -A | -V | -L ] [ <pathname> | <name> ]
udntap-n2-sas>

suicidaleggroll · 08-13-2012, 02:21 PM

You could try running "mount"

samkhan83 · 08-13-2012, 02:24 PM

Sir, this is not a RHEL system. This is a storage system.

Code:

udntap-n2-sas> mount
mount not found.  Type '?' for a list of commands
udntap-n2-sas>

samkhan83 · 08-13-2012, 02:25 PM

Code:

udntap-n2-sas> uname
uname not found.  Type '?' for a list of commands
udntap-n2-sas> ?
?                   fpolicy             nfsstat             smtape
acpadmin            fsecurity           nis                 snap
aggr                ftp                 options             snaplock
arp                 halt                orouted             snapmirror
backup              help                partner             snapvault
bmc                 hostname            passwd              snmp
cdpd                httpstat            ping                software
cf                  ide_savecore        ping6               source
charmap             ifconfig            pktt                sp
cifs                ifgrp               portset             stats
clone               ifstat              priority            storage
config              igroup              priv                sysconfig
date                ipsec               qtree               sysstat
dcb                 ipspace             quota               timezone
df                  iscsi               radius              traceroute
disk                key_manager         rdate               traceroute6
disk_fw_update      keymgr              rdfile              ups
dns                 license             reallocate          uptime
download            lock                reboot              useradmin
du                  logger              restore             version
dump                logout              rlm                 vfiler
echo                lun                 route               vlan
ems                 man                 routed              vmservices
environment         maxfiles            rshstat             vol
exportfs            mt                  sasadmin            vscan
fcadmin             nbtstat             sasstat             wcc
fcnic               ndmpcopy            savecore            wrfile
fcp                 ndmpd               sectrace            ypcat
fcstat              ndp                 secureadmin         ypgroup
file                netdiag             setup               ypmatch
filestats           netstat             shelfchk            ypwhich
flexcache           nfs                 sis
udntap-n2-sas>

suicidaleggroll · 08-13-2012, 02:41 PM

It doesn't have to be RHEL in order to run mount, many NAS systems run various distributions of linux. Given that list of commands, I'd say yours does too, it's just trimmed things down quite a bit.

Either way, I don't think you need to know the underlying filesystem to answer your questions. #1 is caused by root squash. #2 seems kind of pointless anyway, but there might be a way to get around it. Why can't you simply mount the NAS directly from each machine that needs it instead of daisy chaining the mount from machine to machine?