Bug#968049: Failed to kill unit rsyslog.service: Input/output error

[Harald Dunkel]

Package: systemd
Version: 241-7~deb10u4

logrotate.service dies with

● logrotate.service - Rotate log files
    Loaded: loaded (/lib/systemd/system/logrotate.service; static; vendor preset: enabled)
    Active: activating (start) since Fri 2020-08-07 00:00:01 CEST; 346ms ago
      Docs: man:logrotate(8)
            man:logrotate.conf(5)
  Main PID: 359518 (logrotate)
     Tasks: 3 (limit: 618789)
    Memory: 1.9M
    CGroup: /system.slice/logrotate.service
            └─359518 /usr/sbin/logrotate /etc/logrotate.conf

Aug 07 00:00:01 srvvm01.ac.aixigo.de systemd[1]: Starting Rotate log files...
Aug 07 00:00:01 srvvm01.ac.aixigo.de logrotate[359518]: Failed to kill unit rsyslog.service: Input/output error
Aug 07 00:00:01 srvvm01.ac.aixigo.de logrotate[359518]: error: error running non-shared postrotate script for /var/log/syslog of '/var/log/syslog
Aug 07 00:00:01 srvvm01.ac.aixigo.de logrotate[359518]: '


Looking closely this seems to be the part that is broken:

# systemctl kill -s HUP rsyslog.service
Failed to kill unit rsyslog.service: Input/output error


rsyslog *does* receive the HUP, as /var/log/messages seems to indicate:

Aug  7 10:48:53 srvvm01 rsyslogd:  [origin software="rsyslogd" swVersion="8.1901.0" x-pid="96" x-info="https://www.rsyslog.com"] rsyslogd was HUPed


Apparently only systemd thinks that something went wrong, but
this is sufficient to break log file rotation :-(.

This is highly important. The host in question is our EMail server.
I have to move back to sysvinit, if logging and rotation don't work.

This is an LXC container. Host and container are both running Debian 10
and systemd 241-7~deb10u4.


Regards
Harri