IANA assigns port 2311 to messageservice: Message Service.
sudo ss -tlnp 'sport = :2311'sudo ss -ulnp 'sport = :2311'sudo lsof -nP -i :2311sudo netstat -tlnp | grep ':2311 'netstat -ano | findstr :2311Get-NetTCPConnection -LocalPort 2311 -State Listen | Select LocalAddress,OwningProcessnc -vz -w 5 HOST 2311Test-NetConnection HOST -Port 2311nc -vzu -w 5 HOST 2311sudo ufw deny 2311/tcpsudo iptables -A INPUT -p tcp --dport 2311 -j DROPsudo nft add rule inet filter input tcp dport 2311 dropNew-NetFirewallRule -DisplayName 'Block TCP 2311' -Direction Inbound -Protocol TCP -LocalPort 2311 -Action Blocksudo ufw deny 2311/udpsudo iptables -A INPUT -p udp --dport 2311 -j DROPsudo nft add rule inet filter input udp dport 2311 dropNew-NetFirewallRule -DisplayName 'Block UDP 2311' -Direction Inbound -Protocol UDP -LocalPort 2311 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.