Agent Not Connecting

Symptom: Server shows in Live Nodes but stays OFFLINE.

Check 1: Is the agent running?

# Linux
systemctl status sentinel-agent

# macOS
launchctl list | grep sentinel

# Windows
Get-Service SentinelGridAgent

# Docker
docker ps | grep sentinel-agent

Check 2: Network connectivity

curl -H "x-api-key: YOUR_API_KEY" YOUR_SERVER/api/agents/heartbeat

Should return `{"ok":true}`.

Check 3: Logs

# Linux
journalctl -u sentinel-agent -n 50

# macOS
tail -50 /var/log/sentinel-agent.log

# Windows
Get-Content "C:\Program Files\Sentinel Grid Agent\agent.log" -Tail 50

Check 4: API key

Verify the key matches what's in dashboard: Live Nodes → Click server → API Key

Common fixes

- Restart: `systemctl restart sentinel-agent` - Firewall: allow outbound HTTPS (443) + WebSocket - DNS: test `nslookup YOUR_SERVER`