All ports
Port561/UDP
monitorPort
561
Protocol
UDP
Category
Well-Known
Service
monitor
What is port 561?
Port 561/UDP is a Well-Known port, assigned by IANA for widely recognized services. It is associated with the monitor service.
Useful commands
nmapnmap -p 561 -sV example.comnetcatnc -zv example.com 561curlcurl -v http://example.com:561/telnettelnet example.com 561bash(echo > /dev/udp/example.com/561) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 561/udpDeny
sudo ufw deny 561/udpiptablesAllow
sudo iptables -A INPUT -p udp --dport 561 -j ACCEPTDeny
sudo iptables -D INPUT -p udp --dport 561 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=561/udpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 561" dir=in action=allow protocol=UDP localport=561Security Risks
- Unauthorized access to the service
- Data exposure if the service is unauthenticated
- Outdated versions with vulnerabilities
- Incorrect service configuration
Frequently Asked Questions
What service runs on port 561/UDP?
Port 561/UDP is associated with the monitor service. No detailed description is available in the IANA registry.
Is it safe to expose port 561 to the Internet?
It depends on the service and configuration. Port 561 (monitor) is a Well-Known port. If you need to expose it, keep the service updated, use strong authentication, and configure a firewall. It's always recommended to restrict access by IP when possible.
How do I check if port 561 is open?
You can use nmap: `nmap -p 561 -sV example.com`, netcat: `nc -zv example.com 561`, or the bash command: `(echo > /dev/udp/example.com/561) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 561 on my firewall?
On Linux with UFW: `sudo ufw allow 561/udp` (open) or `sudo ufw deny 561/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 561 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 561" dir=in action=allow protocol=UDP localport=561`.
What applications and services use port 561?
Port 561/UDP is used by the monitor service. Specific uses depend on the software and configuration. Check our related tools section for more information.