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Port 70 (gopher)

IANA assigns port 70 to gopher: Gopher.

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

IANA assignment

Service nameProtoDescriptionAssigneeReference
gopher TCP Gopher Mark McCahill -
gopher UDP Gopher Mark McCahill -

Check what is listening on port 70

Linux: is anything listening on TCP 70?
sudo ss -tlnp 'sport = :70'
Linux: UDP 70
sudo ss -ulnp 'sport = :70'
Linux / macOS: which process owns the port
sudo lsof -nP -i :70
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':70 '
Windows (Command Prompt)
netstat -ano | findstr :70
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 70 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 70
From Windows
Test-NetConnection HOST -Port 70
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 70

Block port 70 in the firewall

ufw
sudo ufw deny 70/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 70 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 70 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 70' -Direction Inbound -Protocol TCP -LocalPort 70 -Action Block
ufw
sudo ufw deny 70/udp
iptables
sudo iptables -A INPUT -p udp --dport 70 -j DROP
nftables
sudo nft add rule inet filter input udp dport 70 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 70' -Direction Inbound -Protocol UDP -LocalPort 70 -Action Block

Related ports

68DHCP client (BOOTP)69TFTP71netrjs-172netrjs-2

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