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// Other services

Port 71: Remote Job Service

Port 71 is assigned by IANA to netrjs-1 (Remote Job Service).

71

How netrjs-1 works

Other services
client:71netrjs-1response client:71netrjs-1response

The client sends a request to port 71 and the netrjs-1 service answers.

Transport
TCP · UDP
Exposure risk
not rated depends on the program listening
Encryption
Unknownnot stated by the registry
IANA status
Assigned1 registered service
Range
Well-known (0-1023)
01 Security

Is port 71 dangerous?

We have no specific security note for port 71. Its risk depends on the program actually listening on it. General advice for other services services:

  • Close the port if nothing on the host needs it.
  • Identify the process that listens on it (commands below) before opening it in a firewall.
  • Expose a service only to the networks that use it.
02 Registry

IANA registry entries for port 71

ServicePortTransportDescriptionReferenceUpdated
netrjs-1 71 TCP, UDP Remote Job Service - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 71, and is it reachable?

Linux

sudo ss -ltnup 'sport = :71'      # process listening on 71
sudo lsof -nP -i :71

macOS

sudo lsof -nP -i :71

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 71 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 71
netstat -ano | findstr :71

From another machine

nmap -p 71 -sV <host>
sudo nmap -sU -p 71 <host>
nc -zv <host> 71

Block it in the firewall

sudo ufw deny 71/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 71" -Direction Inbound -LocalPort 71 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 71 used for?

Port 71 is assigned by IANA to netrjs-1 (Remote Job Service).

Is port 71 TCP or UDP?

Port 71 is registered for TCP and UDP.

Is it safe to open port 71?

It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Close the port if nothing on the host needs it.

How do I check if port 71 is open?

On Linux run "ss -ltnup 'sport = :71'", on macOS "lsof -nP -i :71", and on Windows "netstat -ano | findstr :71" to see the local process. From another machine, "nmap -p 71 <host>" shows whether it is reachable.

05 Related

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