All ports
Port3491/TCP
swr-portPort
3491
Protocol
TCP
Category
Registered
Service
swr-port
What is port 3491?
Port 3491/TCP is a Registered port, registered with IANA for specific applications. It is associated with the swr-port service.
SWR Port
Useful commands
nmapnmap -p 3491 -sV example.comnetcatnc -zv example.com 3491curlcurl -v http://example.com:3491/telnettelnet example.com 3491bash(echo > /dev/tcp/example.com/3491) 2>/dev/nullFirewall commands
UFWAllow
sudo ufw allow 3491/tcpDeny
sudo ufw deny 3491/tcpiptablesAllow
sudo iptables -A INPUT -p tcp --dport 3491 -j ACCEPTDeny
sudo iptables -D INPUT -p tcp --dport 3491 -j ACCEPTfirewalldAllow
sudo firewall-cmd --permanent --add-port=3491/tcpWindowsAllow
netsh advfirewall firewall add rule name="Open Port 3491" dir=in action=allow protocol=TCP localport=3491Security 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- Outdated versions with vulnerabilities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 3491/TCP?
Port 3491/TCP is associated with the swr-port service. SWR Port
Is it safe to expose port 3491 to the Internet?
It depends on the service and configuration. Port 3491 (swr-port) 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 3491 is open?
You can use nmap: `nmap -p 3491 -sV example.com`, netcat: `nc -zv example.com 3491`, or the bash command: `(echo > /dev/tcp/example.com/3491) 2>/dev/null && echo "Open" || echo "Closed"`.
How do I open or close port 3491 on my firewall?
On Linux with UFW: `sudo ufw allow 3491/tcp` (open) or `sudo ufw deny 3491/tcp` (close). With iptables: `sudo iptables -A INPUT -p tcp --dport 3491 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 3491" dir=in action=allow protocol=TCP localport=3491`.
What applications and services use port 3491?
Port 3491/TCP is used by the swr-port service. Specific uses depend on the software and configuration. Check our related tools section for more information.