Can't connect to postgres using internal network
congdv
HOBBYOP

a month ago

anyone has any idea how to debug that my service can't connect to postgres using internal network (Postgres.railway.internal) but the service connects fine through public url of postgres.

I received this error when trying to connect through internal network

2026/02/06 03:54:54 db connect error: dial tcp: lookup Postgres.railway.internal on [fd12::10]:53: no such host
2026/02/06 03:54:55 db connect error: dial tcp: lookup Postgres.railway.internal on [fd12::10]:53: no such host
2026/02/06 03:54:57 db connect error: dial tcp: lookup Postgres.railway.internal on [fd12::10]:53: no such host
2026/02/06 03:55:06 db connect error: dial tcp: lookup Postgres.railway.internal on [fd12::10]:53: no such host
2026/02/06 03:55:08 db connect error: dial tcp: lookup Postgres.railway.internal on [fd12::10]:53: no such host

Any tips to debug this issue, my app was deployed through docker container. Do I need other configuration for connect through intern network.

Thank you

$10 Bounty

Pinned Solution

congdv
HOBBYOP

a month ago

I think I found an issue about the Postgres why it is failing. It was DNS is case-sensitive in many cloud environments. When your app looks for Postgres.railway.internal (Uppercase).

To avoid that,you go to Postgres instance and change it to lower case postgres.railway.internal

Attachments

image.png

4 Replies

congdv
HOBBYOP

a month ago

I think I found an issue about the Postgres why it is failing. It was DNS is case-sensitive in many cloud environments. When your app looks for Postgres.railway.internal (Uppercase).

To avoid that,you go to Postgres instance and change it to lower case postgres.railway.internal

Attachments

image.png
snugglepilot
PRO

a month ago

This also worked for me, thankyou. Related thread: https://station.railway.com/questions/internal-networking-postgres-railway-in-0187bfa8

Status changed to Open brody • 29 days ago

Railway
BOT

a month ago

Hello!

We're acknowledging your issue and attaching a ticket to this thread.

We don't have an ETA for it, but, our engineering team will take a look and you will be updated as we update the ticket.

Please reply to this thread if you have any questions!

Railway
BOT

a month ago

✅ The ticket Private domain creation issue has been marked as completed.

Loading...