With the telnet command you can test if a port is open.
You can check if a port is open in your network by issuing the telnet command. If it is open, you will see a blank screen after issuing the command:
telnet [domainname or ip] [port]
- [domainname or ip] is the domain name or IP address of the server to which you are trying to connect
- [port] is the port number where the server is listening
If the port is open, you will see a blank screen. This will mean that connection is successful.
In Windows Vista and later you may need to enable telnet first:
- Go to Start -> Control Panel -> Programs.
- Under Programs and features, click Turn Windows features on or off.
- Mark both Telnet Client and Telnet Server.
- Click OK.
telnet rpc.acronis.com 443
If backup to Acronis Cloud is failing, use Acronis Cloud Connection Verification Tool to check the connection.