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Port 347 (fatserv)

IANA assigns port 347 to fatserv: Fatmen Server.

Well-known (system) port, 0-1023 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
fatserv TCP Fatmen Server - -
fatserv UDP Fatmen Server - -

Check what is listening on port 347

Linux: is anything listening on TCP 347?
sudo ss -tlnp 'sport = :347'
Linux: UDP 347
sudo ss -ulnp 'sport = :347'
Linux / macOS: which process owns the port
sudo lsof -nP -i :347
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':347 '
Windows (Command Prompt)
netstat -ano | findstr :347
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 347 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 347
From Windows
Test-NetConnection HOST -Port 347
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 347

Block port 347 in the firewall

ufw
sudo ufw deny 347/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 347 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 347 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 347' -Direction Inbound -Protocol TCP -LocalPort 347 -Action Block
ufw
sudo ufw deny 347/udp
iptables
sudo iptables -A INPUT -p udp --dport 347 -j DROP
nftables
sudo nft add rule inet filter input udp dport 347 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 347' -Direction Inbound -Protocol UDP -LocalPort 347 -Action Block

Related ports

345pawserv346zserv348csi-sgwp349mftp

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