Cannot connect to postgresql-11 from another machine after boot

Hi,

I've been struggling with a strange (to me) issue for awhile. I have
PostgreSQL 11.6 installed on my Ubuntu machine with the data directory
living on a different drive than the one mounted on /. I was observing the
same behavior when my machine was running Gentoo a month ago.

The problem is that after my machine boots, I'm unable to connect to the
server from anywhere except localhost. Running a simple "systemctl restart
postgresql" fixes the problem and allows me to connect from anywhere on my
LAN. Here is an example of this behavior:

swails(at)client ~ $ psql -U postgres -h 192.168.1.3
psql: could not connect to server: Connection refused
Is the server running on host "192.168.1.3" and accepting
TCP/IP connections on port 5432?

swails(at)client ~ $ ssh 192.168.1.3

swails(at)server ~ $ sudo systemctl restart postgresql

swails(at)server ~ $ logout
Connection to 192.168.1.3 closed.

swails(at)client ~ $ psql -U postgres -h 192.168.1.3
Password for user postgres:

So the first connection attempt fails. But when I restart the service and
try again (doing nothing else in between), the connection attempt
succeeds. My workaround has been to simply restart the service every time
my machine reboots, but I'd really like to have a more reliable startup.

Any ideas how to start hunting down the root cause? I think this started
happening after I moved the data directory to another drive.

Thanks,
Jason

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Jason M. Swails