DNS resolution failures (ENOTFOUND) on shared *.up.railway.app domain
jgsa8
HOBBYOP

25 days ago

We're experiencing intermittent getaddrinfo ENOTFOUND errors when calling our service web-production-4fac9.up.railway.app from an external production server (not a local machine — reproduced via direct curl from our partner's production server, ruling out client-side network issues).

Pattern observed: the first request to the domain fails with ENOTFOUND; subsequent requests within seconds succeed. This has been reproduced consistently across multiple sessions over two days.

What we've already ruled out on our end:

  • sleepApplication: false — service does not idle/sleep.
  • No 502/503/522/524 in our Railway logs during the failure windows (expected, since DNS resolution failures never reach our edge/server).
  • No IPv6/dual-stack ambiguity — only an A record exists for our domain.
  • Confirmed via nslookup/dig that the domain resolves correctly most of the time; the failure is intermittent, not persistent.

Additional finding: we also observed socket.gaierror: Temporary failure in name resolution while using railway ssh to connect to our own Postgres instance, from within Railway's own infrastructure — suggesting this may not be isolated to external callers.

We found similar reports in your community forum matching this exact symptom:

Could you investigate whether there's a known issue with DNS resolution on the shared *.up.railway.app edge, particularly around the public networking layer (we noticed your status history shows 99.42% for "public networking" in some US regions during July)?

Service: web-production-4fac9.up.railway.app (also reachable via custom domain api.naap.nouxtech.com, same underlying infra).

Solved$10 Bounty

Pinned Solution

Try adding a custom domain, set the server's DNS to use 1.1.1.1 when accessing web-production-4fac9.up.railway.app, or use a VPN (if possible).

3 Replies

Railway
BOT

25 days ago

This thread has been opened as a bounty so the community can help solve it.

Status changed to Open Railway 25 days ago


Is the service online and healthy?


0x5b62656e5d

Is the service online and healthy?

jgsa8
HOBBYOP

25 days ago

Service is online and healthy right now.

Verified minutes ago from an external machine: GET /health → 200 on 10/10 requests to web-production-4fac9.up.railway.app, {"status":"ok"}. 40/40 clean DNS resolutions, no failures. No container restarts, no 502/503/522/524, no connection errors in logs.

Caveat: our log retention only covers since our latest deploy (a few hours), so this confirms "clean now," not "clean throughout July."

One isolated data point: a single railway ssh connection attempt failed today ("Could not establish SSH connection to application"), succeeded immediately on retry — one occurrence, not a pattern.

Happy to run specific probes if useful for your investigation.


Try adding a custom domain, set the server's DNS to use 1.1.1.1 when accessing web-production-4fac9.up.railway.app, or use a VPN (if possible).


Status changed to Solved 0x5b62656e5d 5 days ago


Welcome!

Sign in to your Railway account to join the conversation.

Loading...