HTTPfy

Port 1542 (gridgen-elmd)

IANA assigns port 1542 to gridgen-elmd.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
gridgen-elmd TCP gridgen-elmd John R Chawner -
gridgen-elmd UDP gridgen-elmd John R Chawner -

Check what is listening on port 1542

Linux: is anything listening on TCP 1542?
sudo ss -tlnp 'sport = :1542'
Linux: UDP 1542
sudo ss -ulnp 'sport = :1542'
Linux / macOS: which process owns the port
sudo lsof -nP -i :1542
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':1542 '
Windows (Command Prompt)
netstat -ano | findstr :1542
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 1542 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 1542
From Windows
Test-NetConnection HOST -Port 1542
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 1542

Block port 1542 in the firewall

ufw
sudo ufw deny 1542/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 1542 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 1542 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 1542' -Direction Inbound -Protocol TCP -LocalPort 1542 -Action Block
ufw
sudo ufw deny 1542/udp
iptables
sudo iptables -A INPUT -p udp --dport 1542 -j DROP
nftables
sudo nft add rule inet filter input udp dport 1542 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 1542' -Direction Inbound -Protocol UDP -LocalPort 1542 -Action Block

Related ports

1540rds1541rds21543simba-cs1544aspeclmd

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