[ovs-dev] [PATCH] rhel/systemd: Prevent deletion of runtime directory.

[Aaron Conole]

Gurucharan Shetty <guru at ovn.org> writes:

> Currently, when we do a 'service openvswitch stop',
> '/var/run/openvswitch' gets deleted. This is a problem
> if you have other users (like OVN) using the same
> runtime directory since we delete all the files
> related to ovsdb-server backing OVN's databases.
>
> This commit fixes it by removing the runtime directory
> information from the systemd unit file.
>
> CC: aconole at redhat.com
> Signed-off-by: Gurucharan Shetty <guru at ovn.org>
> ---
> I don't know whether there are other drawbacks of removing
> 'RuntimeDirectory'

Hi Guru,

I noticed that if I use 'systemctl restart openvswitch' with the
ovn-northd service running, I get the following output:

  11:06:40 aconole {master} ~/git/ovs$ ls -lah /var/run/openvswitch/
  total 24K
  drwxr-xr-x.  2 openvswitch openvswitch  360 Apr  4 11:06 .
  drwxr-xr-x. 44 root        root        1.3K Apr  4 11:06 ..
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:06 br0.mgmt
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:06 br0.snoop
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:06 db.sock
  srwxr-x---.  1 root        root           0 Apr  4 11:06 ovnnb_db.ctl
  -rw-r--r--.  1 root        root           6 Apr  4 11:06 ovnnb_db.pid
  srwxr-x---.  1 root        root           0 Apr  4 11:06 ovnnb_db.sock
  srwxr-x---.  1 root        root           0 Apr  4 11:06 ovn-northd.30673.ctl
  -rw-r--r--.  1 root        root           6 Apr  4 11:06 ovn-northd.pid
  srwxr-x---.  1 root        root           0 Apr  4 11:06 ovnsb_db.ctl
  -rw-r--r--.  1 root        root           6 Apr  4 11:06 ovnsb_db.pid
  srwxr-x---.  1 root        root           0 Apr  4 11:06 ovnsb_db.sock
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:06 ovsdb-server.30569.ctl
  -rw-r--r--.  1 openvswitch openvswitch    6 Apr  4 11:06 ovsdb-server.pid
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:06 ovs-vswitchd.30612.ctl
  -rw-r--r--.  1 openvswitch openvswitch    6 Apr  4 11:06 ovs-vswitchd.pid
  -rw-r--r--.  1 root        root          43 Apr  4 11:06 useropts
  11:06:47 aconole {master} ~/git/ovs$ ps aux | grep ovn-northd\ 
  root     30673  0.0  0.0  27544  2952 ?        S<   11:06   0:00 ovn-northd -vconsole:emer -vsyslog:err -vfile:info --ovnnb-db=unix:/run/openvswitch/ovnnb_db.sock --ovnsb-db=unix:/run/openvswitch/ovnsb_db.sock --no-chdir --log-file=/var/log/openvswitch/ovn-northd.log --pidfile=/run/openvswitch/ovn-northd.pid --detach --monitor
  aconole  30730  0.0  0.0 119532  1048 pts/0    S+   11:07   0:00 grep --color=auto northd 
  11:09:22 aconole {master} ~/git/ovs$ sudo systemctl restart openvswitch.service 11:09:24 aconole {master} ~/git/ovs$ ls -lah /var/run/openvswitch/
  total 24K
  drwxr-xr-x.  2 openvswitch openvswitch  360 Apr  4 11:09 .
  drwxr-xr-x. 44 root        root        1.3K Apr  4 11:09 ..
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:09 br0.mgmt
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:09 br0.snoop
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:09 db.sock
  srwxr-x---.  1 root        root           0 Apr  4 11:09 ovnnb_db.ctl
  -rw-r--r--.  1 root        root           6 Apr  4 11:09 ovnnb_db.pid
  srwxr-x---.  1 root        root           0 Apr  4 11:09 ovnnb_db.sock
  srwxr-x---.  1 root        root           0 Apr  4 11:09 ovn-northd.31264.ctl
  -rw-r--r--.  1 root        root           6 Apr  4 11:09 ovn-northd.pid
  srwxr-x---.  1 root        root           0 Apr  4 11:09 ovnsb_db.ctl
  -rw-r--r--.  1 root        root           6 Apr  4 11:09 ovnsb_db.pid
  srwxr-x---.  1 root        root           0 Apr  4 11:09 ovnsb_db.sock
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:09 ovsdb-server.31160.ctl
  -rw-r--r--.  1 openvswitch openvswitch    6 Apr  4 11:09 ovsdb-server.pid
  srwxr-x---.  1 openvswitch openvswitch    0 Apr  4 11:09 ovs-vswitchd.31203.ctl
  -rw-r--r--.  1 openvswitch openvswitch    6 Apr  4 11:09 ovs-vswitchd.pid
  -rw-r--r--.  1 root        root          43 Apr  4 11:09 useropts

This looks like both the ovn-northd and openvswitch services are
restarting in concert (which is what I'd expect to happen due to the
"Requires=" and "After=" stanzas).

Is there a set of reproduction steps that helps demonstrates the issue?

NOTE: I used 'sudo systemctl start ovn-northd' to start the northd
service.  Also note, this behavior seems to happen regardless of
"RuntimeDirectory" setting.