HTTPfy

Port 2689 (fastlynx)

IANA assigns port 2689 to fastlynx: FastLynx.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
fastlynx TCP FastLynx Dave Sewell -
fastlynx UDP FastLynx Dave Sewell -

Check what is listening on port 2689

Linux: is anything listening on TCP 2689?
sudo ss -tlnp 'sport = :2689'
Linux: UDP 2689
sudo ss -ulnp 'sport = :2689'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2689
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2689 '
Windows (Command Prompt)
netstat -ano | findstr :2689
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2689 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2689
From Windows
Test-NetConnection HOST -Port 2689
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2689

Block port 2689 in the firewall

ufw
sudo ufw deny 2689/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2689 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2689 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2689' -Direction Inbound -Protocol TCP -LocalPort 2689 -Action Block
ufw
sudo ufw deny 2689/udp
iptables
sudo iptables -A INPUT -p udp --dport 2689 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2689 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2689' -Direction Inbound -Protocol UDP -LocalPort 2689 -Action Block

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2687pq-lic-mgmt2688md-cg-http2690hp-nnm-data2691itinternet

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