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Port 9277 (traingpsdata)

IANA assigns port 9277 to traingpsdata: GPS Data transmitted from train to ground network.

Registered (user) port, 1024-49151 UDP

Port 9277 is normally used over UDP; the checker tests TCP only, so a "filtered" result does not mean the UDP service is down.

IANA assignment

Service nameProtoDescriptionAssigneeReference
traingpsdata UDP GPS Data transmitted from train to ground network Alstom Transport Preston -

Registry dates for this port: registered 2012-12-14.

Check what is listening on port 9277

Linux: UDP 9277
sudo ss -ulnp 'sport = :9277'
Linux / macOS: which process owns the port
sudo lsof -nP -i :9277
Windows (Command Prompt)
netstat -ano | findstr :9277
Windows (PowerShell)
Get-NetUDPEndpoint -LocalPort 9277

Test it from outside

UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 9277

Block port 9277 in the firewall

ufw
sudo ufw deny 9277/udp
iptables
sudo iptables -A INPUT -p udp --dport 9277 -j DROP
nftables
sudo nft add rule inet filter input udp dport 9277 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 9277' -Direction Inbound -Protocol UDP -LocalPort 9277 -Action Block

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