10IPS IP & network intelligence
Port 161

Port 161 (SNMP) — check if it's open

Device monitoring (UDP). Should not be exposed publicly.

Port 161 is usually UDP — a TCP check may show closed even when the service works.

Defaults to your IP: 216.73.216.200. Up to 12 ports per check; ranges up to 10 ports (e.g. 8000-8010).

FAQ

What is port 161 used for?

Port 161 — SNMP. Device monitoring (UDP). Should not be exposed publicly.

How do I open port 161?

1) Make sure the app listens on 0.0.0.0, not 127.0.0.1. 2) Allow the port in your firewall (Windows Defender Firewall inbound rule; Linux: ufw allow 161). 3) Forward the port on your router to your computer's LAN IP. 4) Make sure you have a public (non-CGNAT) IP. 5) Verify it here.

Is it safe to keep port 161 open?

Only open it if the service must be reachable from the internet, keep the software patched and use strong authentication. Put databases, SMB, RDP and admin panels behind a VPN.

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