1. A method for a content item block replication protocol, the method performed by a computing system comprising one or more processors and memory, the method comprising: receiving, from a metadata server, an identification of content item blocks, wherein a content item comprises the content item blocks; based, at least in part, on the received identification, storing a replication log entry in a replication log, the replication log entry comprising the identification of content item blocks and an identifier of a content item block server; and based, at least in part, on processing the replication log entry, transmitting, to the content item block server identified in the replication log entry, an offer to send at least one content item block, of the content item blocks of which the content item is composed, to the content item block server identified in the replication log entry; receiving, from the content item block server, an acceptance of the offer to send the at least one content item block; and based, at least in part, on the received acceptance, sending the at least one content item block to the content item block server.