19. September 2017 16:35, "Thomas Lange" <la...@informatik.uni-koeln.de> 
schrieb:

> First, you should read the log files.
> Start with error.log:
> 
>> InRelease Could not connect to localhost:3142 (127.0.0.1). - connect (111: 
>> Connection refused) [IP:
>> 127.0.0.1 3142]
> 
> This is the port of the apt proxy apt-cacher-ng. You can disable using
> this in sources.list.
> 
>> WARNING: These unknown packages are removed from the installation list: 
>> linux-image-amd64
>> initramfs-tools memtest86+ isc-dhcp-client grub-pc
> 
> Ooops. Without a kernel, you machine will not boot.
> 
> Let's look at fai.log. There you see the whole problem. You cannot
> connect to the Debian package mirror.
> 
> You have to fix that. It does not make sense, that the install lcients
> wants to connect localhost for a package repository. So just remove
> the proxy config in sources.list.
> --
> regards Thomas

OK.
The error is very clear. 
Thanks for the advice where to look...

However, I don't understand why it still fails after modifying 
/srv/fai/nfsroot/etc/apt/apt.conf.d/00proxy
root@vm03-fai:/var/log/fai/remote-logs/demohost/last-install# cat 
/srv/fai/nfsroot/etc/apt/apt.conf.d/00proxy
Acquire::http { Proxy "http://faiserver:3142";; };
#Acquire::https { Proxy "https:/faiserver:3142"; };

Where is the configuration to use apt-cacher-ng (which is intended) stored?
demohost should use faiserver:3142 and not localhost:3142

THX

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