Network setup by installer

[Mark Fletcher <mark27q1@gmail.com>]

Hello the list

Can anyone point me at documentation of how the installer sets up 
network interfaces, out of the several ways there are to do it?

I've done a couple of installs of Stretch, one when it was still testing 
and one recently, on different hardware that both had both wired and 
wireless network interfaces. In both cases I chose to install using the 
wired interface even though for normal usage the computer will use the 
wireless interface. The result in both cases was a machine that had its 
wired interface configured but not its wireless one.

In both cases I can configure the wireless LAN using the desktop gui 
widget (KDE in one case, MATE in the other) but then the wireless LAN 
does not become available until someone logs in.

I'd like to be able to log in remotely before anyone logs in locally, so 
need the wireless network interface up before login. I'd therefore like 
to find the configuration the installer did for the wired interface, and 
have the wireless interface come up the same way and at the same time. I 
did no local customisation of the installer and just let it do its 
thing. Where should I be looking for the network configuration in this 
case? amd64 install on mini-ITX type PCs.

Thanks in advance

Mark