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Port 3940 (xecp-node)

IANA assigns port 3940 to xecp-node: XeCP Node Service.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
xecp-node TCP XeCP Node Service Brent McCullough -
xecp-node UDP XeCP Node Service Brent McCullough -

Registry dates for this port: registered 2003-11.

Check what is listening on port 3940

Linux: is anything listening on TCP 3940?
sudo ss -tlnp 'sport = :3940'
Linux: UDP 3940
sudo ss -ulnp 'sport = :3940'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3940
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3940 '
Windows (Command Prompt)
netstat -ano | findstr :3940
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3940 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3940
From Windows
Test-NetConnection HOST -Port 3940
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3940

Block port 3940 in the firewall

ufw
sudo ufw deny 3940/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3940 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3940 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3940' -Direction Inbound -Protocol TCP -LocalPort 3940 -Action Block
ufw
sudo ufw deny 3940/udp
iptables
sudo iptables -A INPUT -p udp --dport 3940 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3940 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3940' -Direction Inbound -Protocol UDP -LocalPort 3940 -Action Block

Related ports

3938dbcontrol-agent, dbcontrol_agent3939aamp3941homeportal-web3942srdp

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