IANA assigns port 3326 to sftu: SFTU.
sudo ss -tlnp 'sport = :3326'sudo ss -ulnp 'sport = :3326'sudo lsof -nP -i :3326sudo netstat -tlnp | grep ':3326 'netstat -ano | findstr :3326Get-NetTCPConnection -LocalPort 3326 -State Listen | Select LocalAddress,OwningProcessnc -vz -w 5 HOST 3326Test-NetConnection HOST -Port 3326nc -vzu -w 5 HOST 3326sudo ufw deny 3326/tcpsudo iptables -A INPUT -p tcp --dport 3326 -j DROPsudo nft add rule inet filter input tcp dport 3326 dropNew-NetFirewallRule -DisplayName 'Block TCP 3326' -Direction Inbound -Protocol TCP -LocalPort 3326 -Action Blocksudo ufw deny 3326/udpsudo iptables -A INPUT -p udp --dport 3326 -j DROPsudo nft add rule inet filter input udp dport 3326 dropNew-NetFirewallRule -DisplayName 'Block UDP 3326' -Direction Inbound -Protocol UDP -LocalPort 3326 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.