IANA assigns port 1665 to netview-aix-5.
sudo ss -tlnp 'sport = :1665'sudo ss -ulnp 'sport = :1665'sudo lsof -nP -i :1665sudo netstat -tlnp | grep ':1665 'netstat -ano | findstr :1665Get-NetTCPConnection -LocalPort 1665 -State Listen | Select LocalAddress,OwningProcessnc -vz -w 5 HOST 1665Test-NetConnection HOST -Port 1665nc -vzu -w 5 HOST 1665sudo ufw deny 1665/tcpsudo iptables -A INPUT -p tcp --dport 1665 -j DROPsudo nft add rule inet filter input tcp dport 1665 dropNew-NetFirewallRule -DisplayName 'Block TCP 1665' -Direction Inbound -Protocol TCP -LocalPort 1665 -Action Blocksudo ufw deny 1665/udpsudo iptables -A INPUT -p udp --dport 1665 -j DROPsudo nft add rule inet filter input udp dport 1665 dropNew-NetFirewallRule -DisplayName 'Block UDP 1665' -Direction Inbound -Protocol UDP -LocalPort 1665 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.