After you create a GoldenGate Cloud Service (GGCS) instance, you can then connect to the virtual machine to perform the setup. The How to connect to GoldenGate Cloud Service provides the instructions on how you can connect to GGCS instances using SSH in PuTTY on Windows and SSH command from LINUX. You can also connect to GGCS instance via SFTP.
I would also recommend you to refer to the Getting Started with GoldenGate Cloud Service Tutorial for additional information.
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