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Port 33333 (dgi-serv)

IANA assigns port 33333 to dgi-serv: Digital Gaslight Service.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
dgi-serv TCP Digital Gaslight Service George Flanagin -

Registry dates for this port: registered 2010-03-02.

Check what is listening on port 33333

Linux: is anything listening on TCP 33333?
sudo ss -tlnp 'sport = :33333'
Linux / macOS: which process owns the port
sudo lsof -nP -i :33333
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':33333 '
Windows (Command Prompt)
netstat -ano | findstr :33333
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 33333 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 33333
From Windows
Test-NetConnection HOST -Port 33333

Block port 33333 in the firewall

ufw
sudo ufw deny 33333/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 33333 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 33333 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 33333' -Direction Inbound -Protocol TCP -LocalPort 33333 -Action Block

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