HTTPfy

Port 71 (netrjs-1)

IANA assigns port 71 to netrjs-1: Remote Job Service.

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

IANA assignment

Service nameProtoDescriptionAssigneeReference
netrjs-1 TCP Remote Job Service - -
netrjs-1 UDP Remote Job Service - -

Check what is listening on port 71

Linux: is anything listening on TCP 71?
sudo ss -tlnp 'sport = :71'
Linux: UDP 71
sudo ss -ulnp 'sport = :71'
Linux / macOS: which process owns the port
sudo lsof -nP -i :71
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':71 '
Windows (Command Prompt)
netstat -ano | findstr :71
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 71 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 71
From Windows
Test-NetConnection HOST -Port 71
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 71

Block port 71 in the firewall

ufw
sudo ufw deny 71/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 71 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 71 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 71' -Direction Inbound -Protocol TCP -LocalPort 71 -Action Block
ufw
sudo ufw deny 71/udp
iptables
sudo iptables -A INPUT -p udp --dport 71 -j DROP
nftables
sudo nft add rule inet filter input udp dport 71 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 71' -Direction Inbound -Protocol UDP -LocalPort 71 -Action Block

Related ports

69TFTP70gopher72netrjs-273netrjs-3

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