SystemD Unit file missing "After=network-online.target" Parameter

Hi,
In the environment

Kernel: Linux use-prod-web01 4.9.0-8-amd64 #1 SMP Debian
4.9.110-3+deb9u4 (2018-08-21) x86_64 GNU/Linux
OS: Debian 9 stretch
PostgreSQL: 9.3.23-2.pgdg90+1

Expected behavior: Postgres starting and binding to the external interface.

Actual behavior: Otherwise Postgres fails to bind to the external
interface at reboots randomly with the following error message:

|2018-09-06 14:02:32 UTC LOG: could not bind IPv4 socket: Cannot assign
requested address 2018-09-06 14:02:32 UTC HINT: Is another postmaster
already running on port 5432? If not, wait a few seconds and retry.
2018-09-06 14:02:32 UTC WARNING: could not create listen socket for
"123.123.123.123"|

Possible fix: Adding the parameter After=network-online.target to it's
SystemD Unit file.

Our setup includes the setting:
listen_addresses = 'localhost,123.123.123.123' (not the real IP)

Do not hesitate to contact me/us with further questions.

All the best
Sebastian

--
*Sebastian Elisa Pfeifer* :: System Administrator
IXOLIT GmbH <https://www.ixolit.com>
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