nfsmount: need a server?

[Sig]

Michael Tautschnig a écrit :
>> kernel /boot/vmlinuz root=/dev/nfs 
>> nfsroot=<the-ip-address-of-my-server>:/srv/fai/nfsroot nfsopts="-ov2" 
>> FAI_FLAGS="verbose,createvt" FAI_ACTION=install 
>> ip=:<the-ip-address-of-my-server>:::::dhcp boot=live
>>
> Hmm, why do you do the ip=:<the-ip-address-of-my-server>: thing? After all, the
> IP is already part of the nfsroot= option. Do things get any better if you do
> ip=dhcp instead?

I tried ip=dhcp instead. It did not help by itself.

> I do agree that this shouldn't matter, but I found the
> klibc-utils scripts to be pretty picky about the way the network configuration
> is expressed.

Picky, you say? (see below)

>> - nfsopts="-ov2" because the install server uses nfs-user-server which is 
>> said to be incompatible (bugged?) with nfsmount default behaviour and the 
>> server can't use nfs-kernel-server because it is not a real server but a 
>> vserver
> [...]
> 
> I do have no idea about vservers, but is it really the case that one can't use
> nfs-kernel-server on these!?

Yeah! This is really the case.

> Anyway, if that should turn out to be true, please
> try with a "real" server and without the nfsopts, just to get closer to the real
> cause of the problem.

Since you told me how picky these scripts are and since the "nfsmount: 
need a server" error message could mean some trouble the script has when 
trying to parse the nfs options, I tried remove the double quotes from 
my nfsopts argument. And I succeeded nfsmounting the nfsroot from my 
vserver (hence using nfs-user-server on it)!

So here is a good kernel line for grub when you want to use a vserver as 
the installation server:

kernel /boot/vmlinuz root=/dev/nfs 
nfsroot=<the-ip-address-of-my-server>:/srv/fai/nfsroot nfsopts=-ov2 
FAI_FLAGS="verbose,createvt" FAI_ACTION=install ip=dhcp boot=live

You'll notice that the nfsopts double quotes disappeared and that I kept 
the simpler ip=dhcp parameter which is less cumbersome than my ip former 
parameter.

Now I reached another obstacle: after the nfsroot is mounted (which can 
be verified from the syslog file on the server), live-initramfs crashes 
with some logs/traces dumped on the screen. The final line looks like this :

[       76.666512] EIP: [<e0a3dc42>] nfs_lookup+0xd2/0x260 [nfs] SS:ESP 
0068:de6fdbf

I don't know how to read the rest of the traces that scrolled out of the 
screen. I don't know how to get the initramfs prompt either. I suspect 
that this new obstacle I am reaching is due to the fact that my nfsroot 
was generated from an ubuntu gutsy and I read that unionfs is bugged on 
gutsy... I'll try the howto I found some time age for working around 
this. Ill let you know if I eventually reach some real success in using 
FAI in such a config.

-- Sig