When the igmp-proxy service fails to start on the first try - there is no backoff and retry like we know from the systemd world.
The root cause is that the systemd unit file used for igmpproxy.service is automatically generated by systemd-sysv-generator.
vyos@vyos# systemctl cat igmpproxy # /run/systemd/generator.late/igmpproxy.service # Automatically generated by systemd-sysv-generator [Unit] Documentation=man:systemd-sysv-generator(8) SourcePath=/etc/init.d/igmpproxy Description=LSB: IGMP multicast routing daemon After=network-online.target After=remote-fs.target Wants=network-online.target [Service] Type=forking Restart=no TimeoutSec=5min IgnoreSIGPIPE=no KillMode=process GuessMainPID=no RemainAfterExit=yes SuccessExitStatus=5 6 ExecStart=/etc/init.d/igmpproxy start ExecStop=/etc/init.d/igmpproxy stop