[Mageia-dev] systemd vs dm

Sat Sep 17 13:02:50 CEST 2011

'Twas brillig, and Dick Gevers at 17/09/11 11:40 did gyre and gimble:
+> On Sat, 17 Sep 2011 11:16:57 +0100, Colin Guthrie wrote about Re:
+> [Mageia-dev] systemd vs dm:
+> 
+>> Well that's slightly disturbing. It seems that rsyslog was started but
+>> not by systemd.
+>>
+>> Can do do some kind of pstree type analysis (perhaps also using cgroups
+>> stuff) to work out what process actually started rsyslog?
+> 
+> pstree is not quite unequivocal, because it shows systemd at the top of
+> every running process, even those surely not started by systemd but e.g. by
+> the current user.
+
+Yeah that's expected. Everything is a child of pid 1 really, but what
+would be interesting is if rsyslog is a direct child of pid 1 or if
+there are any other processes in between, but I guess not.
+
+> But on the other hand systemd has PID 1 so it's reasonable to assume
+> everything stems from it.
+
+Yup.
+
+> Although when I do lsof |grep rsys |grep syst it returns nothing, so
+> perhaps that means rsyslog was not started by systemd: we'd have to compare
+> with a system where systemctl status rsyslog.service gives a better result.
+
+Nah I wouldn't expect rsyslog to know anything specifically about
+systemd, so this would be the expected output.
+
+> "lsof |grep cgrou" returns only one line:
+> 
+> systemd       1             root    6r      DIR               0,18
+> 0        193 /sys/fs/cgroup/systemd/system
+> 
+> I hope this gives some clues.
+
+Sadly not.
+
+What would be useful is to find the pid of rsyslog (mine is 1505), and
+then do:
+[root at jimmy ~]# cat /proc/1505/cgroup
+8:blkio:/
+7:net_cls:/
+6:freezer:/
+5:devices:/
+4:memory:/
+3:cpuacct,cpu:/system/rsyslog.service
+2:cpuset:/
+1:name=systemd:/system/rsyslog.service
+
+
+If it looks similar to mine then it has been started by systemd but it's
+somehow "lost" that info.
+
+
+I wonder, do you do anything special with either /var /var/run or /run
+directories? Are they on separate partitions or anything?
+
+Col
+
+
+
+
+-- 
+
+Colin Guthrie
+mageia(at)colin.guthr.ie
+http://colin.guthr.ie/
+
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