On 17/12/2025 at 18:56, travis meeks wrote:
I encountered an issue where the Debian Installer (d-i) persisted an
incorrect initial network configuration despite my correcting it
during the installation steps.
Yes, AFAICS here is how it works:
- during "Configure the network", netcfg writes "basic" network
configuration files (/etc/network/interfaces /etc/networks /etc/hostname
/etc/resolv.conf /etc/hosts) and configuration files for NetworkManager
and Netplan in the installer environment;
- during "Install the base system", base-installer.d/40netcfg copies
"basic" network configuration files to the target environment;
- during "Finish the installation",
finish-install.d/55netcfg-copy-config writes configuration files for
NetworkManager or Netplan and re-writes /etc/network/interfaces with
only the loopback interface in the target environment if either package
is installed.
So nothing updates "basic" network configuration files in the target
environment if you reconfigure the network after installing the base
system. It does not affect only the target system after the
installation, it may also affect the ability to use a mirror in
"Configure the package manager" and "Select and install software" if the
the original DNS configuration is wrong.
Maybe a possible option would be to copy "basic" network configuration
files to the target system if "Configure the network" is re-run after
"Install the base system" ? In rescue mode, the target system is mounted
only when in "Enter rescue mode" so it should be fine. Not sure about
live-installer though.
