Re: cannot use btrfs for nfs server

[Hugo Mills <hugo@carfax.org.uk>]

   I'm using it on NFSv3 and it works fine for me.

   Hugo.

On Fri, Jul 09, 2021 at 09:23:14AM +0200, Forza wrote:
> Hello everyone, 
> 
> ---- From: Ulli Horlacher <framstag@rus.uni-stuttgart.de> -- Sent: 2021-07-09 - 08:53 ----
> 
> > On Fri 2021-07-09 (01:05), Graham Cobb wrote:
> >> On 08/07/2021 23:17, Ulli Horlacher wrote:
> >> 
> >> > 
> >> > I have waited some time and some Ubuntu updates, but the bug is still there:
> >> 
> >> Yes: find and du get confused about seeing inode numbers reused in what
> >> they think is a single filesystem.
> > 
> > A lot of tools aren't working correctly any more, even ls:
> > 
> > root@tsmsrvj:~# ls -R /nfs/localhost/fex | wc 
> > ls: /nfs/localhost/fex/spool: not listing already-listed directory
> > 
> > In consequence many cronjobs and montoring tools will fail :-(
> > 
> > 
> >> You can eliminate the problems by exporting and mounting single
> >> subvolumes only 
> > 
> > This is not possible at our site, we use rotating snapshots created by a
> > cronjob.
> > 
> > 
> 
> Have you tried using the fsid= export option in /etc/exports? 
> 
> Example:
> /media/nfs/  192.168.0.*(fsid=20000001,rw,sync,no_subtree_check,no_root_squash)
> 
> We're using this with Btrfs subvols without issues. We use NFSv4 so I do not know how this works with NFSv3. 
> 
> Example:
> ## On the Ubuntu NFS server:
> # btrfs sub list -o .
> ID 5384 gen 345641 top level 258 path volume/nfs_ssd/132bbc3e-aed1-15a5-f30d-9515e490e62c/subvol1
> ID 5385 gen 345640 top level 258 path volume/nfs_ssd/132bbc3e-aed1-15a5-f30d-9515e490e62c/subvol2
> 
> ## On the NFS client:
> [09:20 srv01 132bbc3e-aed1-15a5-f30d-9515e490e62c]# ll
> total 0
> drwxr-xr-x 1 root root 6 Jul  9 09:17 subvol1
> drwxr-xr-x 1 root root 0 Jul  9 09:17 subvol2
> [09:20 srv01 132bbc3e-aed1-15a5-f30d-9515e490e62c]# touch subvol1/foo
> [09:20 srv01 132bbc3e-aed1-15a5-f30d-9515e490e62c]# touch subvol2/bar
> [09:20 srv01 132bbc3e-aed1-15a5-f30d-9515e490e62c]# touch foobar
> [09:20 srv01 132bbc3e-aed1-15a5-f30d-9515e490e62c]# ll -R
> .:
> total 0
> -rw-r--r-- 1 root root  0 Jul  9 09:20 foobar
> drwxr-xr-x 1 root root 12 Jul  9 09:20 subvol1
> drwxr-xr-x 1 root root  6 Jul  9 09:20 subvol2
> 
> ./subvol1:
> total 0
> -rw-r--r-- 1 root root 0 Jul  9 09:17 bar
> -rw-r--r-- 1 root root 0 Jul  9 09:20 foo
> 
> ./subvol2:
> total 0
> -rw-r--r-- 1 root root 0 Jul  9 09:20 bar
> 
> 
> 

-- 
Hugo Mills             | Modern medicine does not treat causes: headaches are
hugo@... carfax.org.uk | not caused by a paracetamol deficiency.
http://carfax.org.uk/  |
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