Package: systemd Version: 229-1 Severity: important Hi,
systemd 229 has taken over the code to send and accept router solicitations in IPv6. Unfortunately, it does only send a single RS immediately after the link comes up, and does not retry if no RA comes in. Unfortunately, bigger switches do not immediately begin forwarding packets after a link was brought up but take a few seconds before the port actually enters forwarding state. On Cisco Catalyst Switches in default configuration, this typically takes 30 seconds until the port is set to spanning-tree portfast. On HP ProCurve switches, it takes 6 to 10 seconds unless LACP and STP negotiation is completed. LACP can be turned off, STP cannot. When a system running IPv6 with systemd 229 is connected to such a switch, the system doesn't get IPv6 on startup, and it doesn't acquire IPv6 on the next regular RA because of #815793. This makes IPv6 completely unuseable. Going back to systemd 226 fixes the issue. With systemd 229, if one forces the switch port in the forwarding state by inserting a dumb switch between the "big" switch and the Linux system, one sees the RA sent by systemd, and IPv6 works. But one cannot possible use dumb switches just to fix systemd's shortcomings. This is a showstopper for IPv6 with systemd. I would like to ask the Debian systemd maintainers to use their discretion to set either this or #815793's severity to any RC value, as both behavioral anomalities of systemd are blatant violations of the IPv6 RFCs. systemd should only migrate to testing when it doesn't break IPv6 any more. Greetings Marc