CyberHunter
// Other services

Port 3530: Grid Friendly

Port 3530 is assigned by IANA to gf (Grid Friendly).

3530

How gf works

Other services
client:3530gfresponse client:3530gfresponse

The client sends a request to port 3530 and the gf 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
Registered (1024-49151)
01 Security

Is port 3530 dangerous?

We have no specific security note for port 3530. 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 3530

ServicePortTransportDescriptionReferenceUpdated
gf 3530 TCP, UDP Grid Friendly - 2002-06

// source: IANA service name and port number registry

03 Check it

Which program uses port 3530, and is it reachable?

Linux

sudo ss -ltnup 'sport = :3530'      # process listening on 3530
sudo lsof -nP -i :3530

macOS

sudo lsof -nP -i :3530

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 3530 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 3530
netstat -ano | findstr :3530

From another machine

nmap -p 3530 -sV <host>
sudo nmap -sU -p 3530 <host>
nc -zv <host> 3530

Block it in the firewall

sudo ufw deny 3530/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 3530" -Direction Inbound -LocalPort 3530 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 3530 used for?

Port 3530 is assigned by IANA to gf (Grid Friendly).

Is port 3530 TCP or UDP?

Port 3530 is registered for TCP and UDP.

Is it safe to open port 3530?

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 3530 is open?

On Linux run "ss -ltnup 'sport = :3530'", on macOS "lsof -nP -i :3530", and on Windows "netstat -ano | findstr :3530" to see the local process. From another machine, "nmap -p 3530 <host>" shows whether it is reachable.

05 Related