Re-building nfsroot in multi-arch environment

[Holger Parplies]

Hi,

George {Skip} F VerDuin wrote on 2015-10-20 21:38:29 -0400 [Re-building nfsroot in multi-arch environment]:
> [...]
> Background:  I have three nfsroots that are important to me: nfsroot, 
> nfsroot-i386, nfsroot-amd64.  Faiserver is on an AMD-64 bladeserver host 
> therefore today nfsroot & nfsroot-amd64 are probably extremely similar.  

do you actually need separate NFS root directories for i386 and amd64? I
haven't tried it, so I might be mistaken, but in theory, an i386 NFS root
under an amd64 kernel should be able to chroot into an amd64 system, should
it not? If I'm correct, you could

* boot an amd64 kernel and mount the i386 NFS root to install an amd64 system
  (of course you'd need an amd64 basefile)
* boot an i386 kernel and mount the i386 NFS root to install an i386 system
  (with the i386 basefile)

Of course, that won't work for other architectures, and you still want a
separate NFS root for experimenting. This is just a side note.

> [...]
> Now when I "diff setup.log setup-amd64.log" I find the following excerpt:
> 
> 1321,1323c1327
> < Re-exporting directories for NFS kernel daemon...exportfs: Failed to 
> stat /srv/fai/nfsroot-amd64: No such file or directory
> < exportfs: Failed to stat /srv/fai/nfsroot-i386: No such file or directory
> < .
> ---
> > Re-exporting directories for NFS kernel daemon....
> 
> [...]
> I grepped /usr/lib/fai/ and /usr/sbin/ to find the 
> source of the Re-exporting output line without finding it.

It's in your NFS server's init script (reload action).

> Now I'm curious to know the thinking behind Re-exporting to nfsroots 
> other than the one being built at the moment.

It's simply an 'exportfs -r' triggered by 'nfs-{kernel,user}-server reload'.

> It puts my -tango version at risk as a minimum (certainly not earth
> shattering).

Not really. Either it's in /etc/exports and already exported anyway, or it
won't be re-exported. 'fai-setup' only adds an entry for the NFS root it
has built, and only if it's not there already.

Regards,
Holger