HTTPfy

Port 4127 (unikeypro)

IANA assigns port 4127 to unikeypro: NetUniKeyServer.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
unikeypro TCP NetUniKeyServer Raymond Chaw -
unikeypro UDP NetUniKeyServer Raymond Chaw -

Registry dates for this port: registered 2007-05.

Check what is listening on port 4127

Linux: is anything listening on TCP 4127?
sudo ss -tlnp 'sport = :4127'
Linux: UDP 4127
sudo ss -ulnp 'sport = :4127'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4127
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4127 '
Windows (Command Prompt)
netstat -ano | findstr :4127
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4127 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4127
From Windows
Test-NetConnection HOST -Port 4127
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 4127

Block port 4127 in the firewall

ufw
sudo ufw deny 4127/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4127 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4127 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4127' -Direction Inbound -Protocol TCP -LocalPort 4127 -Action Block
ufw
sudo ufw deny 4127/udp
iptables
sudo iptables -A INPUT -p udp --dport 4127 -j DROP
nftables
sudo nft add rule inet filter input udp dport 4127 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 4127' -Direction Inbound -Protocol UDP -LocalPort 4127 -Action Block

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4125opsview-envoy4126ddrepl4128nufw4129nuauth

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