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Port 3319 (sdt-lmd)

IANA assigns port 3319 to sdt-lmd: SDT License Manager.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
sdt-lmd TCP SDT License Manager Salvo Nassisi -
sdt-lmd UDP SDT License Manager Salvo Nassisi -

Check what is listening on port 3319

Linux: is anything listening on TCP 3319?
sudo ss -tlnp 'sport = :3319'
Linux: UDP 3319
sudo ss -ulnp 'sport = :3319'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3319
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3319 '
Windows (Command Prompt)
netstat -ano | findstr :3319
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3319 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3319
From Windows
Test-NetConnection HOST -Port 3319
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3319

Block port 3319 in the firewall

ufw
sudo ufw deny 3319/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3319 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3319 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3319' -Direction Inbound -Protocol TCP -LocalPort 3319 -Action Block
ufw
sudo ufw deny 3319/udp
iptables
sudo iptables -A INPUT -p udp --dport 3319 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3319 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3319' -Direction Inbound -Protocol UDP -LocalPort 3319 -Action Block

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Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.