All ports
Port2728/UDP
sqdrPort
2728
Protocol
UDP
Category
Registered
Service
sqdr
What is port 2728?
Port 2728/UDP is a Registered port, registered with IANA for specific applications. It is associated with the sqdr service.
SQDR
Useful commands
nmapnmap -p 2728 -sV example.comnetcatnc -zv example.com 2728curlcurl -v http://example.com:2728/telnettelnet example.com 2728bash(echo > /dev/udp/example.com/2728) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 2728/udpDeny
sudo ufw deny 2728/udpiptablesAllow
sudo iptables -A INPUT -p udp --dport 2728 -j ACCEPTDeny
sudo iptables -D INPUT -p udp --dport 2728 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=2728/udpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 2728" dir=in action=allow protocol=UDP localport=2728Security 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- Outdated versions with vulnerabilities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 2728/UDP?
Port 2728/UDP is associated with the sqdr service. SQDR
Is it safe to expose port 2728 to the Internet?
It depends on the service and configuration. Port 2728 (sqdr) is a Registered 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 2728 is open?
You can use nmap: `nmap -p 2728 -sV example.com`, netcat: `nc -zv example.com 2728`, or the bash command: `(echo > /dev/udp/example.com/2728) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 2728 on my firewall?
On Linux with UFW: `sudo ufw allow 2728/udp` (open) or `sudo ufw deny 2728/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 2728 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 2728" dir=in action=allow protocol=UDP localport=2728`.
What applications and services use port 2728?
Port 2728/UDP is used by the sqdr service. Specific uses depend on the software and configuration. Check our related tools section for more information.