When we need to add IP address to existing Receive Connector we can add it using Exchange Management Console in Server Configuration, Hub Transport.
This solution is fast when you need to add few IP addresses.
But if you need to add many IP addresses then better option is to use Exchange Management Console and Powershell
To get list of Receive Connectors we can run command:
We will get list of all Receive Connectors available on all HUB Transport Exchange Servers.
If we want to list Receive Connectors available on specified server then we need to add parameter -server like below:
Get-ReceiveConnector -server ServerName
Now we have list of Receive Connectors, we need to check Identity from this list to use it to get list of all IP addresses assigned to Receive Connector.
Run following command to get all IP addresses from Receive Connector:
(Get-ReceiveConnector -identity "servername\receiveconnector_name").RemoteIPRanges