Paste your Coolify deploy error. Get the exact fix.
Self Host Guide is a free, no-login tool that diagnoses Coolify and Traefik deploy errors and gives you the exact ordered steps that resolve them. The same checks a senior dev runs, in the right order. Paste an error from your browser, build log, or terminal and get the fix in seconds.
Common Coolify deploy errors
- NET::ERR_CERT_AUTHORITY_INVALID
- TRAEFIK DEFAULT CERT / self-signed certificate
- www.domain.com cert error but apex works
- DNS resolves to the wrong IP / not propagating
- Timeout / no response / container not starting
- Loads via server curl but not in the browser
- acme: error: 429 :: POST :: too many certificates already issued for exact set of domains, retry after ...
- unable to obtain ACME certificate for domains "your-domain.com": unable to generate a certificate for the domains [your-domain.com]: error: one or more domains had a problem: [your-domain.com] acme: error presenting token / authorization failed
- ERR_TOO_MANY_REDIRECTS — This page isn't working. your-domain.com redirected you too many times.
- no available server (Traefik 503) behind your Coolify domain after a successful deploy
- Nixpacks was unable to generate a build plan for this app. / No setup or build phase could be determined (could not determine how to build the app)
- sh: 1: vite: not found (exit code 127) — also seen as "tsc: not found", "next: not found", "react-scripts: not found" during npm run build
- FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory / Build script returned non-zero exit code: 137 (OOMKilled)
- 502 Bad Gateway (Traefik) — build succeeds and container runs, but your-domain.com returns 502 Bad Gateway
- Healthcheck failed / Container is unhealthy — new container never receives traffic, deploy rolls back to the old container (or shows 404 "No available server")
- Build-time error: process.env.NEXT_PUBLIC_* / VITE_* / API URL is undefined during build — values set in Coolify are empty in the built bundle (e.g. ReferenceError or fetch to "undefined")
- ECONNREFUSED / ENOTFOUND / connection to server at "postgres" port 5432 failed
- Coolify dashboard won't load / This site can't be reached
- ENOSPC: no space left on device
- WebSocket connection to 'wss://<your-domain>:6001/app/...' failed (UI shows "WARNING: Cannot connect to real-time service")
- Coolify auto deploy not working / GitHub webhook shows no deliveries after a push
- git@github.com: Permission denied (publickey) / Failed to read Git source
- Oops something is not okay, are you okay? 😢
- Error response from daemon: pull access denied / unauthorized: authentication required
- Coolify volume data lost after redeploy / a new empty volume is created every deploy
- Deployment stuck in "Queued" / "In Progress" forever, Force Start doesn't help, no logs appear
- SERVICE_FQDN is empty / COOLIFY_URL is wrong or blank inside the container
- toomanyrequests: retry-after ... pulling ghcr.io/coollabsio/coolify-helper
- Bind for 0.0.0.0:3000 failed: port is already allocated
- failed to solve with frontend dockerfile.v0: failed to read dockerfile