One or more processing platforms are configured to implement at least a first site of a multi-site storage system. The first site comprises a first file system resident at the first site, and a replicated version of a second file system. The second file system is resident at a second site of the multi-site storage system, and the replicated version of the second file system is resident at the first site. Virtual block storage appliances running on respective virtual machines of the first site interact with one another and with similar appliances at the second site to allow the replicated version of the second file system to be synchronized at a cache level with the second file system, and to allow a replicated version of the first file system at the second site to be synchronized at a cache level with the first file system at the first site.