# Troubleshooting

### Collect logs

```bash
docker compose ps
docker compose logs --no-color > syntho.log
```

{% hint style="info" %}
You can share `syntho.log` with Syntho Support at <support@syntho.ai>.
{% endhint %}

### Quick triage

1. Check container status: `docker compose ps`.
2. Check logs: `docker compose logs -f`.
3. Confirm host ports are reachable (or via reverse proxy).
4. Confirm `.env` matches your access method (HTTP vs HTTPS).

### UI not reachable

* Check containers: `docker compose ps`.
* Check logs: `docker compose logs -f`.
* Confirm your reverse proxy / firewall exposes port `3000` (or your configured port).

<details>

<summary>Common causes</summary>

* Wrong `FRONTEND_DOMAIN` / `FRONTEND_PORT` in `.env`.
* Reverse proxy not forwarding websockets.
* TLS enabled at the proxy, but Syntho configured for `http` (cookie/security mismatch).

</details>

### Image pull failures

Fix:

Use the registry host and credentials provided by Syntho to login with:

```bash
docker login syntho.azurecr.io -u <USERNAME> -p <PASSWORD>
```

{% hint style="info" %}
Ensure that `syntho.azurecr.io` is added to your firewall allowlist to enable image pulls
{% endhint %}

Then:

```bash
docker compose pull
docker compose up -d
```

### Login loop / can’t stay logged in

If TLS is terminated at a reverse proxy / load balancer / Ingress, Syntho must be configured for `https`.

If Syntho is configured for `http`, browsers can reject cookies.

Symptoms include login loops or sessions not sticking.

Fix:

* Set the frontend protocol to `https`.
* Disable secure cookies.

### Backend / Core API errors (5xx)

Check which service errors:

```bash
docker compose logs -f backend
docker compose logs -f backend-worker
docker compose logs -f core-api
docker compose logs -f core-api-worker
```

If you use external PostgreSQL/Redis, verify network access from the host.

### External PostgreSQL issues

Checks:

* Host can reach PostgreSQL (DNS, routing, firewall, security groups).
* User has permissions to create tables and run migrations.
* DB names match your `.env`.

If you use the bundled PostgreSQL from `deployment-tools`, the default database names are:

* `syntho-backend` (Backend)
* `syntho-core` (Core API)


---

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