CyberHunter
// Other services

Port 216: Computer Associates Int'l License Server

Port 216 is assigned by IANA to CAIlic (Computer Associates Int'l License Server).

216

How CAIlic works

Other services
client:216CAIlicresponse client:216CAIlicresponse

The client sends a request to port 216 and the CAIlic service answers.

Transport
TCP · UDP
Exposure risk
not rated depends on the program listening
Encryption
Unknownnot stated by the registry
IANA status
Assigned1 registered service
Range
Well-known (0-1023)
01 Security

Is port 216 dangerous?

We have no specific security note for port 216. Its risk depends on the program actually listening on it. General advice for other services services:

  • Close the port if nothing on the host needs it.
  • Identify the process that listens on it (commands below) before opening it in a firewall.
  • Expose a service only to the networks that use it.
02 Registry

IANA registry entries for port 216

ServicePortTransportDescriptionReferenceUpdated
CAIlic 216 TCP, UDP Computer Associates Int'l License Server - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 216, and is it reachable?

Linux

sudo ss -ltnup 'sport = :216'      # process listening on 216
sudo lsof -nP -i :216

macOS

sudo lsof -nP -i :216

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 216 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 216
netstat -ano | findstr :216

From another machine

nmap -p 216 -sV <host>
sudo nmap -sU -p 216 <host>
nc -zv <host> 216

Block it in the firewall

sudo ufw deny 216/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 216" -Direction Inbound -LocalPort 216 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 216 used for?

Port 216 is assigned by IANA to CAIlic (Computer Associates Int'l License Server).

Is port 216 TCP or UDP?

Port 216 is registered for TCP and UDP.

Is it safe to open port 216?

It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Close the port if nothing on the host needs it.

How do I check if port 216 is open?

On Linux run "ss -ltnup 'sport = :216'", on macOS "lsof -nP -i :216", and on Windows "netstat -ano | findstr :216" to see the local process. From another machine, "nmap -p 216 <host>" shows whether it is reachable.

05 Related