Yes, ESET Remote Administrator (ERA) 6.x can be used in the cloud. Currently, Microsoft Azure, Google Cloud Platform, and Amazon Web Services (AWS) are supported.
A Certified Image is available for Microsoft Azure. To run ERA on Microsoft Azure, make sure you have an Azure account and suitable Virtual Machine running, and then complete the steps in the following Knowledgebase article: Getting started with ESET Remote Administrator (ERA) - Azure.
Google Cloud Platform and AWS
ERA can be installed on either platform using the steps in the following Knowledgebase article: How do I install ESET Remote Administrator? (6.x)