Re: Q: nfs server fails to mount own exported resource, but other client able to mount

[Snow Leopard <snow.leopard.deb@gmail.com>]

Hi,

the mystery has been resolved -- question how did I not catch it right away?

I found that my old Red Hat system and Debian Wheezy/Squeezy resolve 
computer name into ip address in different ways.

Red Hat mount maps computer name to DHCP ip address
Debian mount maps computer name to loopback interface

My attention was somewhat distracted and I've missed that in this case 
in /etc/exports a record should look

not like
/export/home    192.168.0.0/24(rw,sync,no_subtree_check)

but instead
/export/home    192.168.0.0/24(rw,sync,no_subtree_check) 
127.0.0.0/16(rw,sync,no_subtree_check)

The clue was found in logfiles
/var/log/syslog.1:Apr 24 10:29:19 vega mountd[1320]: refused mount 
request from 127.0.1.1 for /export/home (/export/home): unmatched host

The mystery is resolved.

Cheers,
Andy

On 4/24/2014 3:25 AM, Ron Leach wrote:
> On 24/04/2014 09:49, Snow Leopard wrote:
> > Hi,
> >
> > I came across strange "mount" problem on nfs server -- it refuses to
> > mount it's own directory while other nfs clients able mount nfs server
> > exported directoryjust fine
> >
> > 1. nfs server
> > name: install.myclub.com
> > OS: wheeze (Debian)
> > ip: 192.168.0.62
> > /etc/exports: /export/home 192.163.0.0/24(rw,subtree_check)
> > drxwrxwrxw /export/home
> >
> > 2. client1
> > name: meteor.myclub.com
> > OS: Valhalla (Red Hat 7.3)
> > ip: 192.168.0.1
> > mount -t nfs install:myclub.com:/export/home /mnt
> > mounts directory without any error
> >
> > 3. client2
> > name: moon.myclub.com
> > OS: squeeze (Debian)
> > ip: 192.168.0.64
> > mount -t nfs install:myclub.com:/export/home /mnt
> > mounts directory without any error
> >
> > 4. client3 (nfs server itself)
> > name: install.myclub.com
> > OS: wheeze (Debian)
> > ip: 192.168.0.62
> > mount -t nfs 192.168.0.62:/export/home /mnt
> > mounts directory without any error
> >
> > 5. client4 (nfs server itself)
> > name: install.myclub.com
> > OS: wheeze (Debian)
> > ip: 192.168.0.62
> > mount -t nfs install:/export/home /mnt
> > mounts fails with an error
> >
> > mount -v -t nfs install:/export/home /mnt
> > mount.nfs: timeout set for Thu Apr 24 01:21:36 2014
> > mount.nfs: trying text-based options
> > 'vers=4,addr=127.0.1.1,clientaddr=127.0.0.1'
> > mount.nfs: mount(2): Permission denied
> > mount.nfs: access denied by server while mounting install:/export/home
> >
> > mount -v -t nfs install.myclub.com:/export/home /mnt
> > mount.nfs: timeout set for Thu Apr 24 01:22:50 2014
> > mount.nfs: trying text-based options
> > 'vers=4,addr=127.0.1.1,clientaddr=127.0.0.1'
> > mount.nfs: mount(2): Permission denied
> > mount.nfs: access denied by server while mounting
> > install.myclub.com:/export/home
> >
> > The error indicates that when I attempt to mount by using FQDN of nfs
> > server -- the name resolves to 127.0.1.1 and client resolves to
> > 127.0.0.1 .
>
>
> I wonder if it is letting you mount as 'nfs' when you supply the IP 
> address, but is not letting you mount as 'nfs' when you try to address 
> the device locally (which doesn't surprise me).
>
> While I don't use mount, I do use fstab to mount the device containing 
> our nfs export, locally
>
> /dev/md5  /mnt/point  ext4    rw,auto,users,exec
>
> Isn't the 'right' way to mount local filesystems directly as 'ext4' or 
> whatever, and only mount as 'nfs' if the filesystem has to be accessed 
> at another IP address?
>
> regards, Ron