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Port 1455 (esl-lm)

IANA assigns port 1455 to esl-lm: ESL License Manager.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
esl-lm TCP ESL License Manager Abel Chou -
esl-lm UDP ESL License Manager Abel Chou -

Check what is listening on port 1455

Linux: is anything listening on TCP 1455?
sudo ss -tlnp 'sport = :1455'
Linux: UDP 1455
sudo ss -ulnp 'sport = :1455'
Linux / macOS: which process owns the port
sudo lsof -nP -i :1455
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':1455 '
Windows (Command Prompt)
netstat -ano | findstr :1455
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 1455 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 1455
From Windows
Test-NetConnection HOST -Port 1455
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 1455

Block port 1455 in the firewall

ufw
sudo ufw deny 1455/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 1455 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 1455 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 1455' -Direction Inbound -Protocol TCP -LocalPort 1455 -Action Block
ufw
sudo ufw deny 1455/udp
iptables
sudo iptables -A INPUT -p udp --dport 1455 -j DROP
nftables
sudo nft add rule inet filter input udp dport 1455 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 1455' -Direction Inbound -Protocol UDP -LocalPort 1455 -Action Block

Related ports

1453genie-lm1454interhdl-elmd, interhdl_elmd1456dca1457valisys-lm

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