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Port 3409 (networklens)

IANA assigns port 3409 to networklens: NetworkLens Event Port.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
networklens TCP NetworkLens Event Port - -
networklens UDP NetworkLens Event Port - -

Check what is listening on port 3409

Linux: is anything listening on TCP 3409?
sudo ss -tlnp 'sport = :3409'
Linux: UDP 3409
sudo ss -ulnp 'sport = :3409'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3409
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3409 '
Windows (Command Prompt)
netstat -ano | findstr :3409
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3409 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3409
From Windows
Test-NetConnection HOST -Port 3409
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3409

Block port 3409 in the firewall

ufw
sudo ufw deny 3409/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3409 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3409 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3409' -Direction Inbound -Protocol TCP -LocalPort 3409 -Action Block
ufw
sudo ufw deny 3409/udp
iptables
sudo iptables -A INPUT -p udp --dport 3409 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3409 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3409' -Direction Inbound -Protocol UDP -LocalPort 3409 -Action Block

Related ports

3407ldap-admin3408BESApi3410networklenss3411biolink-auth

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