IANA assigns port 1807 to fhsp: Fujitsu Hot Standby Protocol.
sudo ss -tlnp 'sport = :1807'sudo ss -ulnp 'sport = :1807'sudo lsof -nP -i :1807sudo netstat -tlnp | grep ':1807 'netstat -ano | findstr :1807Get-NetTCPConnection -LocalPort 1807 -State Listen | Select LocalAddress,OwningProcessnc -vz -w 5 HOST 1807Test-NetConnection HOST -Port 1807nc -vzu -w 5 HOST 1807sudo ufw deny 1807/tcpsudo iptables -A INPUT -p tcp --dport 1807 -j DROPsudo nft add rule inet filter input tcp dport 1807 dropNew-NetFirewallRule -DisplayName 'Block TCP 1807' -Direction Inbound -Protocol TCP -LocalPort 1807 -Action Blocksudo ufw deny 1807/udpsudo iptables -A INPUT -p udp --dport 1807 -j DROPsudo nft add rule inet filter input udp dport 1807 dropNew-NetFirewallRule -DisplayName 'Block UDP 1807' -Direction Inbound -Protocol UDP -LocalPort 1807 -Action BlockAll port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.