B2 migrate to B3: NFS Problem

[Pressurized]

Hi

Thanks to the forum for solving my issue with sending emails from my b3 (http://forum.excito.net/viewtopic.php?f=9&t=4627).

I'm now hoping for a bit more help with replacing my b2 with a b3.

This time it's NFS which is beating me up. As far as I can tell, I mirrored my b2's NFS setup on the b3 but, when the client PCs try to mount, I get a load of "mount.nfs: access denied by server while mounting" errors.

I've ensured that all my b2 UIDs and GIDs have been duplicated on the b3 so this error is baffling me.

Does anyone know of anything fundamental that I'm missing that has changed between b2's implementation of NFS and b3's.

[Ubi]

the error is not related to your UIDs, the mount process does not care about those. Your solution lies probably in /etc/exports and rerunning exportfs -r.

[Pressurized]

Ubi

Thanks for your reply and you are correct that the mount process is unaffected by the UIDs and GIDs (I understand this and that they would become 'effective' only after mounting). I should not have put that information in my post!

Some more information...

The b3's exports file is a copy of b2's which works perfectly on b2 but not on b3 and I am runnung exportfs -ra whenever I change it.

The problem may lie with the machine names used in exports. For example, a typical line in the file is:

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/home/shares/adrian	corsair(rw,sync,no_subtree_check) garage(rw,sync,no_subtree_check) genesis(rw,sync,no_subtree_check)

With corsair's, garage's and genesis's IP addresses in /etc/hosts on both bubbas. (The machines are all Ubuntu Linux).

showmount -e b2 gives:

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/home/shares/adrian	genesis,garage,corsair

showmount -e b3 gives just:

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/home/shares/adrian	corsair

And it doesn't actually work on the corsair machine! It gives:

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mount.nfs: access denied by server while mounting b3:/home/shares/adrian

Now this LAN-wide b3 share does work:

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/home/storage/music	192.168.0.0/255.255.255.0(rw,sync)

But I'd rather not use this method for personal folders.

Fianlly, when I changed corsair to a non-existant name on both bubbas and ran exportfs, b2 spotted the error while b3 did not:

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adrian@b2:~$ sudo exportfs -ar
exportfs: codsair has non-inet addr
adrian@b2:~$

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adrian@b3:~$ sudo exportfs -ar
adrian@b3:~$

[Ubi]

If this is all copypaste from the cli, why does it say codsair instead of corsair??

Also i personally really dislike dns names in export files. Can you try replacing all names with ip addresses to see if that is where the problem is?

[Pressurized]

codsair was a deliberate temporary mis-spelling of corsair in exports to see what b2 and b3 would do. b2 spotted the error, b3 didn't. This seems to be significant but I haven't been able to figure out why yet.

I'll update exports to use IP addresses rather than aliases and post back with the differnece it makes.

[Ubi]

It seems your b3 has a dns issue rather than an nfs issue =)

[Pressurized]

Ubi

Thanks for your posts.

I've changed the named entries in exports to IP addresses and it hasn't made a practical difference.

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adrian@corsair:~$ sudo mount -a
mount.nfs: access denied by server while mounting b3:/home/shares/adrian
adrian@corsair:~$ showmount -a b3
All mount points on b3:
192.168.0.10:/home/shares/adrian

So even with a pure IP address, access to the mount was still denied and, instead of showing a comma delimited list of available mount points, b3 still only displays the first entry, although it's now an IP address.

Given the above, do you still think that the issue is DNS rather than NFS? Using raw IP addresses, the problem remains. (And actually, I didn't think the entries in /etc/hosts that I set up were actuall domain names but rather just simple aliases for IP addresses on my local network - although I may well be mistaken here!)