How do I check if port 27017 is open?

Enter your public IP or hostname into the scanner tool and click Check. A sub-second raw TCP socket handshake will be initiated from our edge server to port 27017 on your target. If the 3-way handshake finishes with SYN-ACK, the port is OPEN. If an RST packet is returned, the host is reachable but the port is CLOSED. If packets time out without response, the port is FILTERED by an ISP or firewall.

Why does port 27017 show as closed or filtered?

If port 27017 reports CLOSED or FILTERED, confirm that: 1) Your service is actively running and bound to 0.0.0.0 (not just localhost/127.0.0.1); 2) Your router has a port forwarding rule directing external port 27017 to your machine's local IP; 3) Your operating system firewall (Windows Defender Firewall, ufw, or iptables) allows incoming connections on port 27017.

PORT 27017 TCP Database High Risk

Port 27017 (MongoDB NoSQL Database) Open Check

Q: What is port 27017 used for?

Port 27017 is the standard TCP port used for MongoDB NoSQL Database. It is commonly used by MongoDB Server (mongod), MongoDB Compass, Mongoose ODM. Standard instance listener port for MongoDB document-oriented NoSQL database system.

Q: Is port 27017 safe to expose to the public internet?

Exposing port 27017 carries elevated security risks (High risk). Historically targeted by automated ransomware wiping unauthenticated databases. Authentication ('security.authorization: enabled') is mandatory. For remote services, consider placing them behind a secure VPN (such as WireGuard or Tailscale) or restricting inbound access with strict IP firewall rules.

Standard instance listener port for MongoDB document-oriented NoSQL database system.

Live Socket Reachability Probe

Pre-configured for Port 27017

Port Scanner

Quick:

Recent Probes 0

Stored locally in browser • 0 logs on server

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Target hosts and tested ports will appear here automatically for fast 1-click re-testing.

Auto-prunes oldest probes beyond 10 entries (FIFO)

Port Specifications & Network Behavior

Standard Port Number 27017

Primary Service MongoDB NoSQL Database

Transport Protocol TCP

Traffic Classification Database

Residential ISP Status Typically unrestricted by consumer ISPs

Security Exposure High Exposure discouraged without VPN or firewall protection

Security Advisory: MongoDB NoSQL Database (Port 27017)

Historically targeted by automated ransomware wiping unauthenticated databases. Authentication ('security.authorization: enabled') is mandatory.

Recommendation: Keep port 27017 closed to WAN traffic. Connect remotely using WireGuard, Tailscale, or an SSH tunnel.

Port Forwarding & Troubleshooting Checklist

If port 27017 returns CLOSED or FILTERED, work through this verified diagnostic checklist:

1 In /etc/mongod.conf, configure 'net.bindIp: 0.0.0.0'.
2 Verify MongoDB authorization is enabled before exposing to any non-local network.
3 Confirm host firewall and router port forwarding rules.

Verify Host Is Listening Locally

Windows (PowerShell) netstat -ano | findstr :27017

Linux / macOS (Bash) ss -tulpn | grep :27017