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Port 3338 (anet-b)

IANA assigns port 3338 to anet-b: OMF data b.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
anet-b TCP OMF data b - -
anet-b UDP OMF data b - -

Check what is listening on port 3338

Linux: is anything listening on TCP 3338?
sudo ss -tlnp 'sport = :3338'
Linux: UDP 3338
sudo ss -ulnp 'sport = :3338'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3338
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3338 '
Windows (Command Prompt)
netstat -ano | findstr :3338
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3338 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3338
From Windows
Test-NetConnection HOST -Port 3338
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3338

Block port 3338 in the firewall

ufw
sudo ufw deny 3338/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3338 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3338 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3338' -Direction Inbound -Protocol TCP -LocalPort 3338 -Action Block
ufw
sudo ufw deny 3338/udp
iptables
sudo iptables -A INPUT -p udp --dport 3338 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3338 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3338' -Direction Inbound -Protocol UDP -LocalPort 3338 -Action Block

Related ports

3336directv-tick3337directv-catlg3339anet-l3340anet-m

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