---
title: Operations and Troubleshooting
description: This page covers day-to-day operational tasks and solutions to common problems when running DeerFlow App.
---

import { Callout, Cards } from "nextra/components";

# Operations and Troubleshooting

This page covers day-to-day operational tasks and solutions to common problems when running DeerFlow App.

## Log files

All services write logs to the `logs/` directory when started with `make dev`:

| File                 | Service                              |
| -------------------- | ------------------------------------ |
| `logs/langgraph.log` | LangGraph / DeerFlow Harness runtime |
| `logs/gateway.log`   | FastAPI Gateway API                  |
| `logs/frontend.log`  | Next.js frontend dev server          |
| `logs/nginx.log`     | nginx reverse proxy                  |

Tail logs in real time:

```bash
tail -f logs/langgraph.log
tail -f logs/gateway.log
```

Adjust the runtime log level in `config.yaml`:

```yaml
log_level: debug # debug | info | warning | error
```

## Health checks

Verify each service is responding:

```bash
# Gateway health
curl http://localhost:8001/health

# LangGraph health
curl http://localhost:2024/ok

# Through nginx (verifies full proxy chain)
curl http://localhost:2026/api/models
```

## Config upgrade

When you pull a new version of DeerFlow, the `config_version` in `config.example.yaml` may be higher than your `config.yaml`. To merge new fields without losing your customizations:

```bash
make config-upgrade
```

Check the current version in your config:

```bash
grep config_version config.yaml
```

## Common problems

### The app loads but the agent doesn't respond

1. Check `logs/langgraph.log` for startup errors.
2. Verify your model is correctly configured in `config.yaml` with a valid API key.
3. Confirm the API key environment variable is set in the shell that ran `make dev`.
4. Test the model endpoint directly with `curl` to rule out network issues.

---

### Model API errors in the agent response

The agent reports an error like `"No chat models are configured"` or `"model not found"`:

- Check that the `models:` section in `config.yaml` has at least one entry.
- Verify the `name:` field matches what you are requesting in the UI.
- Check that `api_key:` is referencing the correct environment variable and that the variable is set.

---

### Frontend build fails with `BETTER_AUTH_SECRET`

```
Error: BETTER_AUTH_SECRET is required
```

Set the environment variable before building:

```bash
export BETTER_AUTH_SECRET=$(openssl rand -base64 32)
pnpm build
```

Or set it in your `.env` file at the repo root.

---

### Sandbox-related tool failures

If file tools (`read_file`, `ls`, `bash`) fail with permission or path errors:

1. For `LocalSandboxProvider`: check that `allow_host_bash` is set correctly and that the agent has read/write access to the thread data directory.
2. For container sandboxes: verify Docker (or Apple Container) is running and the sandbox image is accessible.
3. For K8s Provisioner: check that the provisioner service is healthy (`curl http://localhost:8002/health`) and that the K8s cluster is reachable.

---

### K8s Provisioner not connecting

```
Connection refused: http://provisioner:8002
```

- Ensure the provisioner service is running: `docker compose ps`.
- Check that `K8S_API_SERVER` is set correctly (should point to the K8s API from inside the container, not `localhost`).
- Verify `~/.kube/config` is mounted and the cluster is reachable from the container host.

---

### MCP tools not loading

If MCP tools appear in `extensions_config.json` but are not available in the agent:

1. Check `logs/langgraph.log` for MCP initialization errors.
2. Verify the MCP server command is installed (`npx`, `uvx`, or the relevant binary).
3. Test the server command manually to confirm it starts without errors.
4. Set `log_level: debug` to see detailed MCP loading output.

---

### Memory not persisting across sessions

- Verify `memory.enabled: true` in `config.yaml`.
- Check that the storage path is writable: `ls -la backend/.deer-flow/`.
- Look for memory update errors in `logs/langgraph.log` (search for "memory").

## Data backup

Thread data and memory are stored under `backend/.deer-flow/`:

```
backend/.deer-flow/
  memory.json           # global agent memory
  agents/               # per-agent memory
  threads/              # thread working directories
    {thread_id}/
      user-data/
        uploads/
        outputs/
  checkpoints.db        # SQLite checkpoints (if configured)
```

Back up this entire directory to preserve conversation history, artifacts, and learned memory.

In Docker deployments, the bind-mounted host path (`$DEER_FLOW_ROOT/backend/.deer-flow/`) is the source of truth — back up the host path.

## Restarting services

To restart a single service (local deployment):

```bash
make stop
make dev
```

Individual service restart scripts are in `scripts/`. For targeted restarts, you can kill and relaunch individual processes manually using the PIDs in the log files.

<Cards num={2}>
  <Cards.Card
    title="Deployment Guide"
    href="/docs/application/deployment-guide"
  />
  <Cards.Card title="Configuration" href="/docs/application/configuration" />
</Cards>
