ubuntu@lp1939255-b:~$ dpkg -l systemd|grep systemd ii systemd 237-3ubuntu10.51 amd64 system and service manager ubuntu@lp1939255-b:~$ sudo dhclient ens8 ens9 ens10 ens11 ens12 ens13 ens14 ens15 ubuntu@lp1939255-b:~$ journalctl --no-pager -b -u systemd-resolved -- Logs begin at Sun 2021-09-05 21:36:12 UTC, end at Sun 2021-09-05 21:41:06 UTC. -- ... Sep 05 21:40:57 lp1939255-b systemd[1]: systemd-resolved.service: Start request repeated too quickly. Sep 05 21:40:57 lp1939255-b systemd[1]: systemd-resolved.service: Failed with result 'start-limit-hit'. Sep 05 21:40:57 lp1939255-b systemd[1]: Failed to start Network Name Resolution.
ubuntu@lp1939255-b:~$ dpkg -l systemd|grep systemd ii systemd 237-3ubuntu10.52 amd64 system and service manager ubuntu@lp1939255-b:~$ sudo dhclient ens8 ens9 ens10 ens11 ens12 ens13 ens14 ens15 ubuntu@lp1939255-b:~$ journalctl --no-pager -b -u systemd-resolved -- Logs begin at Sun 2021-09-05 21:36:12 UTC, end at Sun 2021-09-05 21:50:57 UTC. -- ... Sep 05 21:50:57 lp1939255-b systemd[1]: Started Network Name Resolution. ** Tags removed: verification-needed verification-needed-bionic verification-needed-focal ** Tags added: verification-done verification-done-bionic verification-done-focal -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1939255 Title: dhclient triggers systemd-resolved start limit when processing more than 5 interfaces at once Status in systemd package in Ubuntu: Invalid Status in systemd source package in Bionic: Fix Committed Status in systemd source package in Focal: Fix Committed Bug description: [impact] on a system where systemd-resolved is running, if dhclient is used on more than 5 interfaces, it calls the '/etc/dhcp/dhclient-enter- hooks.d/resolved' script multiple times, which then restarts systemd- resolved multiple times, triggering the unit's start-limit throttle which results in the unit entering failed state [test case] on a system with more than 5 available interfaces to run dhclient on (where all the interfaces will get a dhcp response), run dhclient with the interfaces: $ dhclient ens8 ens9 ens10 ens11 ens12 ens13 ens14 ens15 check if systemd-resolved failed: $ journalctl -b -1 -u systemd-resolved ... Aug 09 00:38:08 sf316232-b systemd[1]: systemd-resolved.service: Start request repeated too quickly. Aug 09 00:38:08 sf316232-b systemd[1]: systemd-resolved.service: Failed with result 'start-limit-hit'. Aug 09 00:38:08 sf316232-b systemd[1]: Failed to start Network Name Resolution. [regression potential] failure to start/stop/restart systemd-resolved, or problems adding dhclient-provided DNS nameservers to systemd-resolved [scope] this is needed only for b/f the dhclient 'hook' script is provided by the systemd package in focal and earlier, and needs fixing in those releases in h and later, the 'hook' script is included in the isc-dhcp-client package and notifies systemd-resolved in a more direct way without requiring restarting, and so doesn't trigger the restart limiting. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1939255/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
