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Port 3530 (gf)

IANA assigns port 3530 to gf: Grid Friendly.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
gf TCP Grid Friendly Daivd P Chassin -
gf UDP Grid Friendly Daivd P Chassin -

Registry dates for this port: registered 2002-06.

Check what is listening on port 3530

Linux: is anything listening on TCP 3530?
sudo ss -tlnp 'sport = :3530'
Linux: UDP 3530
sudo ss -ulnp 'sport = :3530'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3530
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3530 '
Windows (Command Prompt)
netstat -ano | findstr :3530
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3530 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3530
From Windows
Test-NetConnection HOST -Port 3530
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3530

Block port 3530 in the firewall

ufw
sudo ufw deny 3530/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3530 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3530 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3530' -Direction Inbound -Protocol TCP -LocalPort 3530 -Action Block
ufw
sudo ufw deny 3530/udp
iptables
sudo iptables -A INPUT -p udp --dport 3530 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3530 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3530' -Direction Inbound -Protocol UDP -LocalPort 3530 -Action Block

Related ports

3528jboss-iiop3529jboss-iiop-ssl3531joltid3532raven-rmp

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