Devices Showing as Unreachable

Problem

Network devices are shown as "unreachable" in the dashboard even though they are working.

Diagnosis

1. Check firewall rules: ICMP (Ping) and SNMP (UDP Port 161) must be allowed
2. Test connectivity manually: ping <IP> and snmpwalk -v2c -c public <IP>
3. Verify DNS resolution if hostnames are used

Solution

Make sure the NetMonitor container is on the same network as the monitored devices or that proper routing is configured.