A content item block replication protocol for multi-premises hosting of digital content items. In one embodiment, for example, a method comprises: receiving, from a server, a server journal entry identifying one or more content item blocks of a content item represented by the server journal entry; storing a replication task log entry corresponding to the server journal entry in a replication task log, the replication task log entry identifying the one or more content item blocks of the content item represented by the server journal entry and identifying a block server; and either offering to send the one or more content item blocks identified in the replication task log entry to the block server identified in the replication task log entry, or downloading the one or more content item blocks identified in the replication task log entry from the block server identified in the replication task log entry.