Can't establish connection to postgres database

Questions / Help
1

I have followed the documentation for creating a postgres database cluster and attaching it to an existing fly app. Unfortunately I’m not able to establish a connection inside the fly app when deploying.

The App is a next.js application with prisma, by building the project I am also running a migration for the database. But the build fails because of failed connection.

#15 48.45 Error: P1001: Can't reach database server at `top2.nearest....`:`5432`

I have also set private_network = true in my fly.toml but with no success.

2

One thing to check before further debugging: is that postgres cluster within the same organization as your app? If one is in “personal”, and the other in “something-else”, the connection will fail. I made that mistake with one of mine once :slight_smile:

1 Like
3

Thank you for the hint! Just checked they’re both in “personal”

4

No problem. It’s not that then.

Next would be checking the database app is ok, running, etc. Try checking its status (scroll down a bit to see further status check commands e.g fly checks list -a name-pg-app), and see if there are any errors shown:

If not, not sure what else to suggest.

5

Database is running ok, all status looks good. Also have been able establishing a connection locally via WireGuard but still no success inside the fly app.

6

I bumped into this, the problem I had is that Ecto was not configured to use ipv6, so I changed runtime.exs to:

  maybe_ipv6 = if System.get_env("ECTO_IPV6"), do: [:inet6], else: []

  config :myapp, MyApp.Repo,
    # other config ...
    socket_options: maybe_ipv6

The ECTO_IPV6 env var seems to be added already by fly.io, but you may need to add it yourself.

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