Bug#837759: network configuration stops working reliably

[Wolfgang Walter]

Package: systemd
Version: 231-6
Severity: grave

Starting with version 231-6 the configuration of network interfaces stops 
working reliably when rebooting a system. Downgrading to 231-5 fixes the 
problem.

Symptoms: If a network interface is configured using /etc/network/interfaces 
it seems that systemd now sometimes removes the configured ip4 and/or ipv6 
addresses in the boot process. It also seems to remove routes of network 
interfaces configured manually or with /etc/network/interfaces if the link 
state changes.

This seems not only be the case with interfaces configured via /etc/network/
interfaces but with any interface one creates and assigns ip addresses 
manually.

I tested this with a script:

#!/bin/sh
if [ "$1" = start ]; then
ip link del TEST >/dev/null 2>&1 || true
ip link add name TEST type dummy
ip -b - <<"EOF"
link set TEST up
addr add 10.10.10.10/32 dev TEST nodad
addr add 2a01:1:1:1::1/128 dev TEST nodad
addr add 2a01:1:1:1::2/128 dev TEST nodad
addr add 2a01:1:1:1::3/128 dev TEST nodad
addr add 2a01:1:1:1::4/128 dev TEST nodad
addr add 2a01:1:1:1::5/128 dev TEST nodad
EOF
ip addr ls TEST
sleep 2
elif [ "$1" = stop ]; then
ip addr flush dev TEST
ip link del TEST
fi

which I start with as a systemd oneshot service with
	Before=systemd-networkd.service

I can see in the journal that TEST has all adresses assigned but with 231-6 it 
looses them again (probably when systemd-networkd.service starts). With 231-5 
or earlier this in not the case.


Regards,
-- 
Wolfgang Walter
Studentenwerk München
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