HTTPfy

Port 2418 (cas)

IANA assigns port 2418 to cas.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
cas TCP cas Akiyoshi Ochi -
cas UDP cas Akiyoshi Ochi -

Check what is listening on port 2418

Linux: is anything listening on TCP 2418?
sudo ss -tlnp 'sport = :2418'
Linux: UDP 2418
sudo ss -ulnp 'sport = :2418'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2418
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2418 '
Windows (Command Prompt)
netstat -ano | findstr :2418
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2418 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2418
From Windows
Test-NetConnection HOST -Port 2418
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2418

Block port 2418 in the firewall

ufw
sudo ufw deny 2418/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2418 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2418 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2418' -Direction Inbound -Protocol TCP -LocalPort 2418 -Action Block
ufw
sudo ufw deny 2418/udp
iptables
sudo iptables -A INPUT -p udp --dport 2418 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2418 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2418' -Direction Inbound -Protocol UDP -LocalPort 2418 -Action Block

Related ports

2416rmtserver2417composit-server2419attachmate-s2s2420dslremote-mgmt

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