[systemd-devel] How to mount NFS prior to start postgresql from this volume

[Simon McVittie]

On 01/07/16 15:44, wolfgang.wagner at riwa-gis.de wrote:
> Maybe it is caused by this  (ssome lines before in journalctl-log):

I don't know whether it's causal, but dependency loops are never good news.

> Jul 01 16:09:57 postgis1 systemd[1]: Cannot add dependency job for unit
> display-manager.service, ignoring: Unit display-manager.service f
> Jul 01 16:09:57 postgis1 systemd[1]: Found ordering cycle on
> basic.target/start
> Jul 01 16:09:57 postgis1 systemd[1]: Found dependency on
> sysinit.target/start
> Jul 01 16:09:57 postgis1 systemd[1]: Found dependency on
> rpcbind.service/start
> Jul 01 16:09:57 postgis1 systemd[1]: Found dependency on
> network-online.target/start
> Jul 01 16:09:57 postgis1 systemd[1]: Found dependency on
> vmware-tools.service/start
> Jul 01 16:09:57 postgis1 systemd[1]: Found dependency on basic.target/start
> Jul 01 16:09:57 postgis1 systemd[1]: Breaking ordering cycle by deleting
> job rpcbind.service/start
> Jul 01 16:09:57 postgis1 systemd[1]: Job rpcbind.service/start deleted
> to break ordering cycle starting with basic.target/start

I think I recognize this from when Debian switched default init system
to systemd.

Part of the problem is that rpcbind is an early-boot service (rcS,
sysinit.target) but the version in Debian 8 doesn't have a native
systemd service, only an LSB init script in /etc/init.d. systemd has a
generator that can fake a service from that script, but because it
doesn't have all the necessary information and has to make some
assumptions, it's easy for it to create a dependency loop that could
have been avoided when using native services.

This is fixed in testing (stretch); a backport of the version from
stretch, or introducing native systemd services locally, would probably
help. See <https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=748074> for
more on this general topic. rpcbind's Debian maintainer does not appear
to be working on it any more, so I suspect it might be in danger of not
releasing with Debian 9; if NFS is important to you, you might want to
look into taking over its maintenance.

I think vmware-tools might be in a similar situation: relatively early
boot, but only a LSB init script, not a native systemd service.

-- 
Simon McVittie
Collabora Ltd. <http://www.collabora.com/>