# Troubleshooting Quick Reference

**Last Updated:** 2025-01-20  
**Document Version:** 1.0  
**Status:** Active Documentation

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## Quick Reference: Common Issues and Solutions

### Container Issues

| Issue | Quick Check | Quick Fix |
|-------|-------------|-----------|
| Container won't start | `pct status <vmid>` | `pct start <vmid>` |
| Container out of disk | `pct exec <vmid> df -h` | `pct set <vmid> -rootfs <size>` |
| Container out of memory | `pct list --full` | `pct set <vmid> -memory <mb>` |
| Container network issue | `pct exec <vmid> ping 8.8.8.8` | Check network config |
| Container service down | `pct exec <vmid> systemctl status <service>` | `pct exec <vmid> systemctl restart <service>` |

---

### Network Issues

| Issue | Quick Check | Quick Fix |
|-------|-------------|-----------|
| Can't reach container | `ping <container-ip>` | Check firewall rules |
| DNS not working | `pct exec <vmid> nslookup google.com` | Check DNS config |
| Port not accessible | `nc -zv <ip> <port>` | Check port forwarding |
| VLAN not working | `ip addr show` | Check VLAN config |
| Cloudflare tunnel down | `pct status 102` | Restart cloudflared container |

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### Service Issues

| Issue | Quick Check | Quick Fix |
|-------|-------------|-----------|
| Besu node not syncing | `pct exec <vmid> curl http://localhost:8545` | Check logs, restart |
| RPC endpoint down | `curl https://rpc-http-pub.d-bis.org` | Check Nginx, restart RPC |
| Blockscout not loading | `curl http://192.168.11.140:80` | Check Blockscout status |
| Cloudflare tunnel error | `pct logs 102` | Check tunnel config |

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### Performance Issues

| Issue | Quick Check | Quick Fix |
|-------|-------------|-----------|
| High CPU usage | `pct list --full` | Check processes, limit CPU |
| High memory usage | `pct list --full` | Increase memory or optimize |
| Disk I/O high | `iostat -x 1` | Check disk usage, optimize |
| Network latency | `ping <target>` | Check network, optimize routing |

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### Quick Diagnostic Commands

#### Container Health Check
```bash
# Check container status
pct status <vmid>

# Check container resources
pct list --full | grep <vmid>

# Check container logs
pct logs <vmid> --tail 50

# Check container network
pct exec <vmid> ip addr show
```

#### Network Health Check
```bash
# Test connectivity
ping -c 4 192.168.11.1

# Check DNS
nslookup google.com

# Check routes
ip route show

# Test port
nc -zv <ip> <port>
```

#### Service Health Check
```bash
# Check Besu RPC
curl -X POST http://localhost:8545 -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'

# Check Blockscout
curl http://192.168.11.140:80

# Check Cloudflare tunnel
pct status 102
```

---

### Common Error Messages

| Error Message | Likely Cause | Solution |
|---------------|--------------|----------|
| "No space left on device" | Disk full | Free up space or expand disk |
| "Connection refused" | Service not running | Start service or check firewall |
| "Network unreachable" | Network config issue | Check network configuration |
| "Permission denied" | Permission issue | Check file permissions |
| "Container not found" | Wrong VMID | Verify VMID with `pct list` |

---

### Emergency Procedures

#### Container Won't Start
1. Check status: `pct status <vmid>`
2. Check logs: `pct logs <vmid>`
3. Check config: `pct config <vmid>`
4. Try manual start: `pct start <vmid>`
5. If still failing, check resources: `pct list --full`

#### Network Completely Down
1. Check router: `ping 192.168.11.1`
2. Check switch: Physical connection
3. Check Proxmox network: `ip addr show`
4. Check firewall: `iptables -L`
5. Restart network: `systemctl restart networking`

#### Service Critical Failure
1. Check service status: `systemctl status <service>`
2. Check logs: `journalctl -u <service> -n 50`
3. Restart service: `systemctl restart <service>`
4. If persistent, check configuration
5. Escalate to detailed troubleshooting guide

---

### Quick Fixes by Service

#### Besu Node
```bash
# Restart Besu container
pct restart <vmid>

# Check Besu logs
pct logs <vmid> | grep -i error

# Check Besu RPC
curl -X POST http://localhost:8545 -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'
```

#### RPC Endpoint
```bash
# Check RPC container
pct status 2500

# Check Nginx
pct exec 105 nginx -t

# Restart Nginx
pct exec 105 systemctl restart nginx

# Test RPC endpoint
curl https://rpc-http-pub.d-bis.org
```

#### Cloudflare Tunnel
```bash
# Check tunnel status
pct status 102

# Check tunnel logs
pct logs 102 | tail -50

# Restart tunnel
pct restart 102

# Verify tunnel health
# Check Cloudflare dashboard
```

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## Related Documentation

- **[../09-troubleshooting/TROUBLESHOOTING_FAQ.md](/docs/09-troubleshooting/TROUBLESHOOTING_FAQ.md)** ⭐⭐⭐ - Complete troubleshooting FAQ
- **[../09-troubleshooting/TROUBLESHOOTING_DECISION_TREE.md](../09-troubleshooting/TROUBLESHOOTING_DECISION_TREE.md)** ⭐⭐ - Troubleshooting decision tree
- **[../03-deployment/OPERATIONAL_RUNBOOKS.md](../03-deployment/OPERATIONAL_RUNBOOKS.md)** ⭐⭐ - Operational runbooks

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**Last Updated:** 2025-01-20  
**Review Cycle:** Quarterly
