<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=koi8-r"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style></style> </head> <body lang="EN-US" link="#0563C1" vlink="#954F72"> <div class="WordSection1"> Hello,<o:p></o:p> <o:p></o:p> I’m interested in a particular scenario which has been mentioned on mailing lists before:<o:p></o:p> <a href="https://www.mail-archive.com/search?l=systemd-devel@lists.freedesktop.org&q=subject:%22%5C%5Bsystemd%5C-devel%5C%5D+after%3Duser.slice+not+enforced%22&o=newest&f=1">https://www.mail-archive.com/search?l=systemd-devel@lists.freedesktop.org&q=subject:%22%5C%5Bsystemd%5C-devel%5C%5D+after%3Duser.slice+not+enforced%22&o=newest&f=1</a><o:p></o:p> <o:p></o:p> <o:p></o:p> about stopping a database service. For the moment I’m considering the simplest case where systemd controls both the start and stopping of the service (though I’m mainly interested in the stop).<o:p></o:p> <o:p></o:p> <o:p></o:p> What I’m finding in testing is that I cannot find an approach that stops the service before its user processes get killed first.<o:p></o:p> <o:p></o:p> Following the discussion in the article above I planned to have an additional target that existed after multi-user.target – post-multi-user.target (a bit like graphical.target). The new target initially seemed like over-kill but I thought it would be the best way to order the shutdown.<o:p></o:p> <o:p></o:p> [root@lab01 ~]# systemd-analyze critical-chain<o:p></o:p> The time after the unit is active or started is printed after the "@" character.<o:p></o:p> The time the unit takes to start is printed after the "+" character.<o:p></o:p> <o:p></o:p> post-multi-user.target @42.912s<o:p></o:p> оmulti-user.target @42.911s<o:p></o:p> оpostfix.service @41.143s +1.766s<o:p></o:p> оnetwork.target @41.121s<o:p></o:p> оnetwork.service @39.661s +1.457s<o:p></o:p> ...<o:p></o:p> <o:p></o:p> <o:p></o:p> I find that stopping and starting the service works fine as does isolating the target (actual config below) e.g.<o:p></o:p> e.g.<o:p></o:p> # systemctl stop dbora.service<o:p></o:p> # systemctl start dbora.service<o:p></o:p> <o:p></o:p> # systemctl isolate multi-user.target<o:p></o:p> # systemctl isolate post-multi-user.target<o:p></o:p> <o:p></o:p> But if I reboot I can see from the logs that a key process has gone before the shutdown script has run. This means the database has not had a chance to have a clean shutdown.<o:p></o:p> <o:p></o:p> Is the scenario I’m after something I can configure for? I’m sure it would be a popular use case. I can’t have the sessions I see in CGROUP name=systemd:/user.slice/ being killed before my stop script has completed – it has to hold-up that process.<o:p></o:p> <o:p></o:p> <o:p></o:p> My test configuration looks like:<o:p></o:p> <o:p></o:p> <o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# systemctl get-default<o:p></o:p> post-multi-user.target<o:p></o:p> <o:p></o:p> <o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# cat dbora.service<o:p></o:p> [Unit]<o:p></o:p> Description=The Oracle Database Service<o:p></o:p> Requires=post-multi-user.target<o:p></o:p> After=post-multi-user.target<o:p></o:p> <o:p></o:p> [Service]<o:p></o:p> Type=oneshot<o:p></o:p> RemainAfterExit=yes<o:p></o:p> KillMode=none<o:p></o:p> # Set this to something larger if it has an impact<o:p></o:p> TimeoutStopSec=0<o:p></o:p> <o:p></o:p> ExecStart=/u01/app/oracle/product/12.1.0.2/dbhome_1/bin/dbora start<o:p></o:p> ExecStop=/u01/app/oracle/product/12.1.0.2/dbhome_1/bin/dbora stop<o:p></o:p> <o:p></o:p> [Install]<o:p></o:p> # Puts wants directive for the other units in the relationship<o:p></o:p> WantedBy=post-multi-user.target<o:p></o:p> <o:p></o:p> <o:p></o:p> <o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# cat post-multi-user.target<o:p></o:p> [Unit]<o:p></o:p> Description=A level after multi-user for e.g. databases to run in<o:p></o:p> Requires=multi-user.target<o:p></o:p> Wants=dbora.service<o:p></o:p> After=multi-user.target<o:p></o:p> AllowIsolate=yes<o:p></o:p> <o:p></o:p> Sanity check config:<o:p></o:p> <o:p></o:p> <o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# systemctl show -p Requires,Wants,Requisite,BindsTo,PartOf,Before,After post-multi-user.target<o:p></o:p> Requires=multi-user.target<o:p></o:p> Requisite=<o:p></o:p> Wants=systemd-readahead-replay.service systemd-readahead-collect.service dbora.service<o:p></o:p> BindsTo=<o:p></o:p> PartOf=<o:p></o:p> Before=systemd-readahead-done.service systemd-readahead-done.timer dbora.service<o:p></o:p> After=multi-user.target<o:p></o:p> <o:p></o:p> <o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# systemctl show -p Requires,Wants,Requisite,BindsTo,PartOf,Before,After dbora.service<o:p></o:p> Requires=basic.target post-multi-user.target<o:p></o:p> Requisite=<o:p></o:p> Wants=system.slice<o:p></o:p> BindsTo=<o:p></o:p> PartOf=<o:p></o:p> Before=shutdown.target<o:p></o:p> After=post-multi-user.target system.slice systemd-journald.socket basic.target<o:p></o:p> lab01.localdomain-root [] /lib/systemd/system#<o:p></o:p> <o:p></o:p> <o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# systemd-analyze verify dbora.service<o:p></o:p> lab01.localdomain-root [] /lib/systemd/system# systemd-analyze verify post-multi-user.target<o:p></o:p> lab01.localdomain-root [] /lib/systemd/system#<o:p></o:p> <o:p></o:p> <o:p></o:p> Thanks,<o:p></o:p> <o:p></o:p> Ray Nichols<o:p></o:p> Oracle DBA<o:p></o:p> <o:p></o:p> </div> </body> </html>