HTTPfy

Port 6999 (iatp-normalpri)

IANA assigns port 6999 to iatp-normalpri: IATP-normalPri.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
iatp-normalpri TCP IATP-normalPri John Murphy -
iatp-normalpri UDP IATP-normalPri John Murphy -

Check what is listening on port 6999

Linux: is anything listening on TCP 6999?
sudo ss -tlnp 'sport = :6999'
Linux: UDP 6999
sudo ss -ulnp 'sport = :6999'
Linux / macOS: which process owns the port
sudo lsof -nP -i :6999
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':6999 '
Windows (Command Prompt)
netstat -ano | findstr :6999
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 6999 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 6999
From Windows
Test-NetConnection HOST -Port 6999
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 6999

Block port 6999 in the firewall

ufw
sudo ufw deny 6999/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 6999 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 6999 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 6999' -Direction Inbound -Protocol TCP -LocalPort 6999 -Action Block
ufw
sudo ufw deny 6999/udp
iptables
sudo iptables -A INPUT -p udp --dport 6999 -j DROP
nftables
sudo nft add rule inet filter input udp dport 6999 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 6999' -Direction Inbound -Protocol UDP -LocalPort 6999 -Action Block

Related ports

6997MobilitySrv6998iatp-highpri7000Cassandra inter-node / AirPlay7001Cassandra TLS / WebLogic

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.