`service postgresql start` exit before actual starts happened

[ShockwaveNN]

I used this Dockerfile to reproduce this problem:

```
FROM ubuntu:16.04
RUN apt-get update && apt-get install -y postgresql sudo
RUN service postgresql start && \
    sudo -u postgres psql -c "CREATE DATABASE test1;"
RUN service postgresql start && \
    sudo -u postgres psql -c "CREATE DATABASE test2;"

```
When second `service postgresql start` performed I got and error:
```
psql: FATAL: the database system is starting up
The command '/bin/sh -c service postgresql start && sudo -u postgres psql -c "CREATE DATABASE test;"' returned a non-zero code: 2
```

But if I add some timeout after start command everything is fine
```
FROM ubuntu:16.04
RUN apt-get update && apt-get install -y postgresql sudo
RUN service postgresql start && \
    sudo -u postgres psql -c "CREATE DATABASE test1;"
RUN service postgresql start && \
    sleep 30 && \
    sudo -u postgres psql -c "CREATE DATABASE test2;"
```

Versions are:
dpkg -l | grep postgre
ii postgresql 9.5+173ubuntu0.2 all object-relational SQL database (supported version)
ii postgresql-9.5 9.5.16-0ubuntu0.16.04.1 amd64 object-relational SQL database, version 9.5 server
ii postgresql-client-9.5 9.5.16-0ubuntu0.16.04.1 amd64 front-end programs for PostgreSQL 9.5
ii postgresql-client-common 173ubuntu0.2 all manager for multiple PostgreSQL client versions
ii postgresql-common 173ubuntu0.2 all PostgreSQL database-cluster manager
ii postgresql-contrib-9.5 9.5.16-0ubuntu0.16.04.1 amd64 additional facilities for PostgreSQL

[Christian Ehrhardt  (paelzer)]

Hi,
this is a good bug, sorry to see it so late.
It is actually very similar to bug 1862138.

Let me summarize:
- postgresql.service is actualyl a target, see
  root@x:~# systemctl cat postgresql
  # /lib/systemd/system/postgresql.service
  # systemd service for managing all PostgreSQL clusters on the system. This
  # service is actually a systemd target, but we are using a service since
  # targets cannot be reloaded.
- the individual clusters are usually synchronous, so if you need that behavior
  you'd need (for the default, or another name if you have others)
  $ systemctl start [e-mail]

That worked well through a few tests:
root@x:/# for i in $(seq 1 100); do systemctl restart [e-mail]; sudo -u postgres psql -c "CREATE DATABASE testme$i;"; done

I'd expect those to aso work on the docker example, but I have to admit I was generally only barely able to trigger the issue in my (LXD) containers.

P.S. Maybe after it is the general bad integration of system services in docker?

[ShockwaveNN (shockwavenn)]

Oh, this was almos one year ago and as far as I concred my original attached Dockerfile with issue is working fine, so I think issue is solved

on

#dpkg -l | grep postgre
ii postgresql 9.5+173ubuntu0.3 all object-relational SQL database (supported version)
ii postgresql-9.5 9.5.19-0ubuntu0.16.04.1 amd64 object-relational SQL database, version 9.5 server
ii postgresql-client-9.5 9.5.19-0ubuntu0.16.04.1 amd64 front-end programs for PostgreSQL 9.5
ii postgresql-client-common 173ubuntu0.3 all manager for multiple PostgreSQL client versions
ii postgresql-common 173ubuntu0.3 all PostgreSQL database-cluster manager
ii postgresql-contrib-9.5 9.5.19-0ubuntu0.16.04.1 amd64 additional facilities for PostgreSQL

[Launchpad Janitor (janitor)]

[Expired for postgresql-9.5 (Ubuntu) because there has been no activity for 60 days.]