Good afternoon! Newbie here, I’ve tried to install Lemmy using Ansible (Debian stable) and I ended up having an issue with the Postgresql connectivity (localhost via socket).
The error message I have is:
thread 'main' panicked at 'Error connecting to postgresql:///lemmy?user=lemmy&host=/var/run/postgresql: connection to server on socket "/var/run/postgresql/.s.PGSQL.5432" failed: No such file or directory
I have updated my /etc/postgresql/15/main/pg_hba.conf from peer to trust to md5 with no success (rebooting Postresql each time).
My config.hjson is:
database: {
uri: "postgresql:///lemmy?user=lemmy&host=/var/run/postgresql"
password: "{{ postgres\_password }}"
}
Any idea / suggestion? Thanks!
PS: cross-posted on the Matrix.org install support chat
My investigations so far have led me to the conclusion that the Ansible install creates multiple docker containers, including one for Lemmy and one for Postgresql. I need now to figure out how inter-container communications work but the host itself is not used.
Ah right, I assumed you were trying to connect the
lemmycontainer to postgres running outside of docker.One important thing to remember with all docker compose files - the service name (the first keys in the
services:configuration) is also the hostname of that container so to ping lemmy (from some other container in that docker compose) you would doping lemmy, same for postgresping postgres- but if the postgres service was nameddb0then it would beping db0.You also do not have to expose ports - all containers in that compose share one network (exposing is for outside access).
All together your postgres config for lemmy should like this:
database: { # name of the postgres database for lemmy database: "lemmy" # username to connect to postgres user: "postgres" # password to connect to postgres password: "xxxxxxx" # host where postgres is running host: "postgres" # port where postgres can be accessed port: 5432 # maximum number of active sql connections pool_size: 10 }Amazingly helpful, thanks!
Ok, the good news is that it works. The bad news is that I don’t understand what changed. 🤨
I don’t get what you mean here. Communication over (linux) socket file and TCP/IP is very different.
After reading your comment, I went back to investigate my install. I can’t remember having changed anything relevant but Lemmy started to function properly, connecting as it should the database. It’s been stable since, even after reboots.
As you suggested, I am using “postgres” as the host, as the service is described in the docker-compose.yml file. The communication is then via TCP/IP and not socket.