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Port 1539 (intellistor-lm)

IANA assigns port 1539 to intellistor-lm: Intellistor License Manager.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
intellistor-lm TCP Intellistor License Manager Ron Vaughn -
intellistor-lm UDP Intellistor License Manager Ron Vaughn -

Check what is listening on port 1539

Linux: is anything listening on TCP 1539?
sudo ss -tlnp 'sport = :1539'
Linux: UDP 1539
sudo ss -ulnp 'sport = :1539'
Linux / macOS: which process owns the port
sudo lsof -nP -i :1539
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':1539 '
Windows (Command Prompt)
netstat -ano | findstr :1539
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 1539 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 1539
From Windows
Test-NetConnection HOST -Port 1539
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 1539

Block port 1539 in the firewall

ufw
sudo ufw deny 1539/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 1539 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 1539 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 1539' -Direction Inbound -Protocol TCP -LocalPort 1539 -Action Block
ufw
sudo ufw deny 1539/udp
iptables
sudo iptables -A INPUT -p udp --dport 1539 -j DROP
nftables
sudo nft add rule inet filter input udp dport 1539 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 1539' -Direction Inbound -Protocol UDP -LocalPort 1539 -Action Block

Related ports

1537sdsc-lm15383ds-lm1540rds1541rds2

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