20. September 2017 11:46, "Thomas Lange" <la...@informatik.uni-koeln.de> 
schrieb:

>> On Wed, 20 Sep 2017 09:36:04 +0000, c.mo...@web.de said:
> 
>> My question is:
>> If I want to upgrade nfsroot (with command fai-setup -kv), do I need to 
>> provide a proxy
> configuration for apt?
> First, you do not have to upgrade your nfsroot, after you've just
> created it. There's no need for it.
> 
> I you like to upgrade the nfsroot later, you will need the peorxy
> config, because you've said you have to use a proxy. But you should
> remove the 02proxy config after you've upgraded your nfsroot, so this
> config is not used by the install clients.
> 
> --
> regards Thomas

I see... this is clear now.
And it works!!!

Just one remark.
If the installation fails, e.g. Temporary failure resolving 
'httpredir.debian.org', fai will disable the existing PXELINUX configuration by 
changing filename to /srv/tftp/fai/pxelinux.cfg/C0A82164.disable
However, after fixing the cause of the failure, I would like to restart the 
client with fai.
But this is then prohibited.
I think you should not disable /srv/tftp/fai/pxelinux.cfg/C0A82164.disable if 
fai fails on client.

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