> ## Documentation Index
> Fetch the complete documentation index at: https://docs.autheo.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Node troubleshooting

> Common issues encountered when running an Autheo Chain validator node and how to resolve them.

## Node won't start

**Check for port conflicts:**

```bash theme={null}
sudo ss -tlnp | grep -E '26656|26657|8545|9090'
```

If another process occupies port 26656 or 26657, either stop it or change the Autheo port in `config/config.toml`.

**Check for config syntax errors:**

```bash theme={null}
autheod start --dry-run --home /path/to/node-home 2>&1 | head -50
```

**Check systemd logs:**

```bash theme={null}
sudo journalctl -u autheod -n 100 --no-pager
```

***

## Node is stuck syncing (`catching_up: true`)

```bash theme={null}
autheod status | jq '.SyncInfo'
```

**Possible causes:**

1. **Not enough peers** — check peer count:
   ```bash theme={null}
   curl -s localhost:26657/net_info | jq '.result.n_peers'
   ```
   If below 3, add persistent peers in `config/config.toml` and restart.

2. **Chain data corrupted** — restore from the official snapshot:
   ```bash theme={null}
   sudo systemctl stop autheod
   rm -rf /path/to/node-home/data/
   wget https://snapshot.autheo.com/data_backup_latest.tar.gz
   tar xzvf data_backup_latest.tar.gz
   mv data/ /path/to/node-home/data/
   cp /secure/backup/priv_validator_state.json /path/to/node-home/data/priv_validator_state.json
   sudo systemctl start autheod
   ```

3. **Wrong genesis file** — ensure `config/genesis.json` matches the network genesis hash.

***

## No peers connecting

1. Verify port 26656 is open in your firewall:
   ```bash theme={null}
   sudo ufw allow 26656/tcp
   ```
2. Add bootstrap peers to `config.toml`:
   ```toml theme={null}
   [p2p]
   persistent_peers = "<node-id>@<ip>:26656,..."
   ```
3. Check that `external_address` is set to your public IP if behind NAT:
   ```toml theme={null}
   external_address = "<your-public-ip>:26656"
   ```

***

## Validator is jailed

```bash theme={null}
autheod query slashing signing-info \
  $(autheod tendermint show-validator --home /path/to/node-home)
```

**Causes:**

* Missing too many consecutive blocks (liveness failure)
* Governance revocation of Sovereign license

**Fix for liveness jailing:**

```bash theme={null}
# 1. Ensure the node is synced and running correctly
autheod status | jq '.SyncInfo.catching_up'

# 2. Unjail
autheod tx slashing unjail \
  --from mykey \
  --chain-id autheo_2127-1 \
  --keyring-backend file

# 3. If license became BOUND after unjail, re-delegate
autheod tx staking delegate <autheovaloper-address> <amount>aauth \
  --from mykey --chain-id autheo_2127-1 --keyring-backend file
```

***

## High memory usage

Autheo Chain uses MemIAVL which requires 8–16 GB of RAM above the process baseline. If you're hitting memory limits:

1. Verify the host meets the minimum 32 GB RAM requirement
2. Check for memory leaks: `sudo journalctl -u autheod -f | grep -i "out of memory"`
3. Increase system swap as a temporary measure
4. Upgrade to the recommended 64 GB RAM configuration

***

## `panic: failed to load latest version` at startup

**Cause**: The chain database is corrupted.

**Fix**: Restore from snapshot (see "Node is stuck syncing" above).

***

## License stuck in BOUND after unjail

See [FAQ: My license is stuck in BOUND after unjailing](/getting-started/faq#my-license-is-stuck-in-bound-after-unjailing-how-do-i-fix-it) for the resolution steps.

***

## `address already in use` on port 8545

The EVM JSON-RPC port is already bound by another process.

```bash theme={null}
# Find the process using port 8545
sudo ss -tlnp | grep 8545

# Either stop the conflicting process or change the EVM port in app.toml:
# [json-rpc]
# address = "0.0.0.0:8546"
```