Hasura and Fly postgres connections

1

I’ve some success, but for some reason now having trouble connecting a service to the database:

  • I have the right url from flyctl postgres attach --postgres-app dbname being passed. (one note there, would be nice if you output a exit 0 saying “already attached” if you run this again)
  • I can psql into the database using the url provided once I have wireguard locally running
  • dig _apps.internal shows the database but not the other service (because it won’t start due to connection issues)
  • on startup the failed app (Hasura app) outputs: “could not translate host name “dish-db.internal” to address: Name or service not known”

I’ll try creating a new one and just see if somehow it’s stuck in a weird state, but any help on how to generally debug this would be great.

Edit: Ah yes, must have been some sort of state bug, after delete and recreate it connected fine.

Edit 2: Seems I needed to re-create apps for it to work again, not sure what happened but after delete + create three of them now connect with *no other changes.

2

Did you get anywhere with this? We’ll go look at Hasura, it sounds like it’s not handling IPv6 properly. This can happen because:

  1. It doesn’t look up AAAA records like it should.
  2. It may require a configuration option to connect to IPv6

This is coming up with lots of libs, so we have some documentation work and exploring to do!

3

Just to note, my other apps (non Hasura) were having trouble connecting too, and once I restarted each they connected. Actually a restart didn’t work, I had to delete and recreate. So perhaps some communication issue in the backend.

4

Next time they’re having trouble, will you ssh into one and see if pinging the cluster IPs works? That’s a strange problem.

7

We found a bug that might’ve caused this. In short, private networking was disabled on some deploys when it shouldn’t be!

Will you give it another try?

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