<div dir="ltr"><div class="gmail_default" style="font-family:comic sans ms,sans-serif">Hi Reindl, I have attached a minimalistic repro along with the codes of all the scripts, service files. I suppose Silvio was able to see the files. Please refer to <a href="https://www.mail-archive.com/systemd-devel@lists.freedesktop.org/msg46055.html">https://www.mail-archive.com/systemd-devel@lists.freedesktop.org/msg46055.html</a>. </div><div class="gmail_default" style="font-family:comic sans ms,sans-serif">I have re-attached the tar again in this email. </div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div>Regards, </div><div>Aravindhan Krishnan...</div></div></div></div> </div> <div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, 7 Jun 2021 at 21:53, Reindl Harald <<a href="mailto:h.reindl@thelounge.net">h.reindl@thelounge.net</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> Am 07.06.21 um 17:57 schrieb Aravindhan Krishnan: > Adding Raghav. > > And sorry the subject should have stated: Discrepancy in using dhclient > b/w ubuntu 20.04 and ubuntu 16.04 and why didn't you fix it in your own reply? to your problem: you have a wild mix of docker, systemd-units and shellscripts but don't provide the source of the scripts nor the systemd unit overly complex for something that can be trivial as: [root@srv-rhsoft:~]$ cat /etc/systemd/system/network-wan-dhcp.service [Unit] Description=Internet DHCP-Client [Service] Type=forking ExecStart=/usr/sbin/dhclient -4 -q --no-pid --request-options subnet-mask,broadcast-address,routers br-wan PermissionsStartOnly=yes SuccessExitStatus=80 Restart=always RestartSec=5 ProtectSystem=strict ProtectHome=yes ReadWritePaths=-/var/lib/dhclient PrivateTmp=yes NoNewPrivileges=yes ProtectKernelTunables=yes ProtectKernelModules=yes ProtectControlGroups=yes MemoryDenyWriteExecute=yes CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_BIND_SERVICE CAP_NET_BROADCAST CAP_NET_RAW LockPersonality=yes PrivateDevices=yes ProtectHostname=yes RestrictNamespaces=yes RestrictRealtime=yes RestrictSUIDSGID=yes ProtectClock=true ProtectKernelLogs=true UMask=077 SystemCallArchitectures=native SystemCallFilter=@system-service @network-io @privileged SystemCallFilter=~@aio @chown @clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io @reboot @resources @swap InaccessiblePaths=-/boot InaccessiblePaths=-/efi InaccessiblePaths=-/root > On Mon, 7 Jun 2021 at 21:26, Aravindhan Krishnan > <<a href="mailto:aravindhank11@gmail.com" target="_blank">aravindhank11@gmail.com</a> <mailto:<a href="mailto:aravindhank11@gmail.com" target="_blank">aravindhank11@gmail.com</a>>> wrote: > > Hi Folks, > > I am finding anomalous behavior when I am trying to run dhclient > process inside my docker container in vanilla Ubuntu 16.04 host. The > service gets into "deactivating" state and is stuck forever. In the > mail I have attached a minimalistic reproduction of the issue seen. > > Working logic: > > * There is a sample trial@.service script which invokes the > `trial` binary with the option passed to the systemd service via > @ option > * The valid options are sleep and dhclient_<interface_name> > * The binary either invokes a long-lived sleep process or dhclient > process on the said interface_name based on the input > * The binary then spawns `kill_trial.sh` script. The script sleeps > for 20 seconds and kills the parent `trial` binary. The kill > signal is SIGKILL in the trial example. In the real-world, this > can be a SIGSEGV indicating a crash in the parent process. > * If the trial binary was started for sleep process things work > fine and service goes into "failed" state as expected > * However, in case of dhclient, the service is stuck in > "deactivating" state if the underlying host OS is Ubuntu 16.04. > This works well if the host is running Ubuntu 20.04. > * We have kept TimeoutStopSec to infinity, because in real-word > deployments, the core collection post a crash takes varying time > depending on the memory config on the host. > > > Steps to reproduce > # tar -xf minimal_repro.tar -C minimal_repro/ > # cd minimal_repro/ > # docker build -t trial . > # docker rm -f trial > # docker run -it -d --net=host --privileged -v > /sys/fs/cgroup:/sys/fs/cgroup:ro --name trial trial > # docker exec -it trial bash > > # systemctl start trial@dhclient_eth1.service > > # #Keep monitoring trial@dhclient_eth1.service -- issue should be > seen within 20-30 seconds on Ubuntu 16.04 host > > # systemctl status trial@dhclient_eth1.service > ● trial@dhclient_eth1.service - Trial > Loaded: loaded (/etc/systemd/system/trial@.service; static; > vendor preset: enabled) > Active: deactivating (stop-sigterm) (Result: signal) since Mon > 2021-06-07 13:19:12 UTC; 1min 11s ago > Process: 55 ExecStartPre=/bin/bash > /etc/systemd/system/trial_service_script.sh pre_start dhclient_eth1 > (code=exited, status=0/SUCCESS) > Process: 56 ExecStart=/bin/bash > /etc/systemd/system/trial_service_script.sh start dhclient_eth1 > (code=killed, signal=KILL) > Main PID: 56 (code=killed, signal=KILL) > Tasks: 0 (limit: 38590) > Memory: 588.0K > CGroup: > /docker/903fca0cee1387b7c2113a36ee5efdb3a25edd1e60584fe5da5d0c5b5ffd8241/system.slice/system-trial.slice/trial@dhclient_eth1.service > > # #NOTE: `Active: deactivating` -- in stuck state > # #Running `systemctl daemon-reload` forces the service to go to > failed state > > # systemctl start trial@sleep.service > > # #Keep monitoring trial@sleep.service -- would be killed in 20-30 > seconds and goes into failed state as expected > > # # systemctl status trial@sleep.service > ● trial@sleep.service - Trial > Loaded: loaded (/etc/systemd/system/trial@.service; static; > vendor preset: enabled) > Active: failed (Result: signal) since Mon 2021-06-07 13:38:19 > UTC; 21s ago > Process: 113 ExecStartPre=/bin/bash > /etc/systemd/system/trial_service_script.sh pre_start sleep > (code=exited, status=0/SUCCESS) > Process: 114 ExecStart=/bin/bash > /etc/systemd/system/trial_service_script.sh start sleep > (code=killed, signal=KILL) > Process: 129 ExecStopPost=/bin/bash > /etc/systemd/system/trial_service_script.sh post_stop sleep > (code=exited, status=0/SUCCESS) > Main PID: 114 (code=killed, signal=KILL) > > Please advise on what can help us in alleviating the issue. _______________________________________________ systemd-devel mailing list <a href="mailto:systemd-devel@lists.freedesktop.org" target="_blank">systemd-devel@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/systemd-devel" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/systemd-devel</a> </blockquote></div>