installation: Create get-network.sh from host information.

installation/20generate-get-network.sh

+#!/bin/bash
+
+# Generate /etc/opt/slapos/get-network.sh
+# from "$GIT_ROOT"/installation/get-network.sh.in
+# using "$GIT_ROOT"/installation/display-host-information.sh
+
+set -e
+
+# get the root of the git repository (requires git to be installed)
+GIT_ROOT=$(git rev-parse --show-toplevel)
+cd "$GIT_ROOT"
+
+source "$GIT_ROOT"/installation/display-host-information.sh
+
+sed "s|%DEFAULT_NETMASK%|$DEFAULT_NETMASK|g;s|%DEFAULT_NETMASK_NUMBER%|$DEFAULT_NETMASK_NUMBER|g;s|%DEFAULT_INTERFACE%|$DEFAULT_INTERFACE|g;s|%DEFAULT_ROUTER%|$DEFAULT_ROUTER|g;s|%DEFAULT_IP%|$DEFAULT_IP|g" "$GIT_ROOT"/installation/get-network.sh.in > /etc/opt/slapos/get-network.sh

installation/get-network.sh.in

+echo -e "nameserver 1.1.1.1\nnameserver 8.8.8.8" > /etc/resolv.conf
+ip a del dev %DEFAULT_INTERFACE% 10.42.42.42/32
+ip a add dev %DEFAULT_INTERFACE% %DEFAULT_IP%/%DEFAULT_NETMASK_NUMBER%
+ip r del default via 10.42.42.42 dev eno1
+ip l set %DEFAULT_INTERFACE% up
+ip r add default via %DEFAULT_ROUTER% dev %DEFAULT_INTERFACE% onlink
+ip r add %DEFAULT_NETMASK% dev %DEFAULT_INTERFACE% proto kernel scope link src %DEFAULT_IP%