Package: systemd-timesyncd Version: 250.4-1 Severity: normal Tags: ipv6 Dear Maintainer,
I'm seeing systemd restart systemd-timesyncd.service approximately every 10 seconds, lining up with when I see a log showing that my router has advertised its IPv6 address. If I run `journalctl -f`, the output is full of lines like the following: ``` Mar 21 15:53:56 lucy.dinwoodie.org dhcpcd[452]: eth0: Router Advertisement from fe80::be99:11ff:fe69:4300 Mar 21 15:53:57 lucy.dinwoodie.org systemd[1]: Stopping Network Time Synchronization... Mar 21 15:53:57 lucy.dinwoodie.org systemd[1]: systemd-timesyncd.service: Deactivated successfully. Mar 21 15:53:57 lucy.dinwoodie.org systemd[1]: Stopped Network Time Synchronization. Mar 21 15:53:57 lucy.dinwoodie.org systemd[1]: Starting Network Time Synchronization... Mar 21 15:53:57 lucy.dinwoodie.org systemd[1]: Started Network Time Synchronization. Mar 21 15:53:57 lucy.dinwoodie.org systemd-timesyncd[6426]: Initial synchronization to time server 162.159.200.1:123 (0.debian.pool.ntp.org). Mar 21 15:54:06 lucy.dinwoodie.org dhcpcd[452]: eth0: Router Advertisement from fe80::be99:11ff:fe69:4300 Mar 21 15:54:07 lucy.dinwoodie.org systemd[1]: Stopping Network Time Synchronization... Mar 21 15:54:07 lucy.dinwoodie.org systemd[1]: systemd-timesyncd.service: Deactivated successfully. Mar 21 15:54:07 lucy.dinwoodie.org systemd[1]: Stopped Network Time Synchronization. Mar 21 15:54:07 lucy.dinwoodie.org systemd[1]: Starting Network Time Synchronization... Mar 21 15:54:07 lucy.dinwoodie.org systemd[1]: Started Network Time Synchronization. Mar 21 15:54:07 lucy.dinwoodie.org systemd-timesyncd[6463]: Initial synchronization to time server 178.62.18.76:123 (0.debian.pool.ntp.org). ``` There's no great immediate impact, but it seems like this shouldn't be happening. And there is clearly some impact in terms of unnecessary disk churn, unnecessary network usage, unnecessary load on NTP servers, and -- still minor, but most relevant to my immediate interests -- ability to spot interesting logs in journald. Some searching online led me to a very old systemd bug[0], but that was apparently resolved in systemd 219, so definitely shouldn't be relevant now. [0]: https://bugs.freedesktop.org/show_bug.cgi?id=87505 Other searches pointed me to other people reporting similar problems[1][2] with no resolution. It's possibly of interest is that they're all folk (like me) running on a Raspberry Pi. At least in my case, however, I understand the only difference between what I'm running and a regular arm64 Debian installation is that there are a few driver and firmware packages shipped from the Raspberry Pi Foundation. Certainly all the systemd packages I'm using have come straight from deb.debian.org repositories. [1]: https://raspberrypi.stackexchange.com/q/133605/145463 [2]: https://forums.raspberrypi.com/viewtopic.php?t=324473 Given that, I suspect whatever the issue is may be due to one or more of (a) folks using Raspberry Pis are going to be running an arm-based architecture, or (b) folks using Pis are more likely to be running very minimal Debian installations, so are more likely to have not installed packages that might not be listed as dependencies but whose absence causes non-obvious problems. Admittedly there's also (c) there's something up with the config that's used on Raspberry Pis by default, but I've done my best to rule that out: I can't see anything in the documentation for dhcpcd, systemd-networkd or systemd-timesyncd that would cause this behaviour, nor anything in any of the configuration in /etc/systemd/. I'm seeing this behaviour on /bullseye (247.3-6), /bullseye-backports (250.4-1~bpoll+1), and /sid (250.4-1). -- System Information: Debian Release: 11.2 APT prefers stable-updates APT policy: (990, 'stable-updates'), (990, 'stable-security'), (990, 'stable'), (850, 'testing'), (500, 'unstable') Architecture: arm64 (aarch64) Foreign Architectures: armhf Kernel: Linux 5.10.103-v8+ (SMP w/4 CPU threads; PREEMPT) Kernel taint flags: TAINT_CRAP Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE not set Shell: /bin/sh linked to /usr/bin/dash Init: systemd (via /run/systemd/system) Versions of packages systemd-timesyncd depends on: ii adduser 3.118 ii libc6 2.33-7 ii systemd 250.4-1 systemd-timesyncd recommends no packages. systemd-timesyncd suggests no packages. -- no debconf information
