1. A method of performing synchronous replication in a data storage system, comprising: storing, in the data storage system, a file that provides a realization of a host file system; receiving, in a file-based format, an IO request specifying data to be written to the host file system; mapping the IO request to a block-based request that specifies data to be written in a block-based format; sending the block-based request to a replication appliance configured to replicate block-based requests at a replication site; receiving an acknowledgement from the replication appliance that the data specified in the block-based request sent to the replication appliance have been persisted; in response to receiving the acknowledgement, processing the block-based request to effect a write operation on the file that provides the realization of the host file system; and configuring, via a GUI (graphical user interface) application, a replication session manager for establishing a set of replication settings for the host file system, wherein the GUI application accepts user input for managing a range of operations of the data storage system, including configuring pool, configuring block-based objects and configuring file-based objects.