IANA assigns port 2001 to wizard: curry.
Port 2001 is normally used over UDP; the checker tests TCP only, so a "filtered" result does not mean the UDP service is down.
sudo ss -ulnp 'sport = :2001'sudo lsof -nP -i :2001netstat -ano | findstr :2001Get-NetUDPEndpoint -LocalPort 2001nc -vzu -w 5 HOST 2001sudo ufw deny 2001/udpsudo iptables -A INPUT -p udp --dport 2001 -j DROPsudo nft add rule inet filter input udp dport 2001 dropNew-NetFirewallRule -DisplayName 'Block UDP 2001' -Direction Inbound -Protocol UDP -LocalPort 2001 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.