An apparatus and method are provided for processing flush requests within a packet network. The apparatus comprises a requester device within the packet network arranged to receive a flush request generated by a remote agent requesting that one or more data items be flushed to a point of persistence. The requester device translates the flush request into a packet-based flush command conforming to a packet protocol of the packet network. A completer device within the packet network that is coupled to a persistence domain incorporating the point of persistence is arranged to detect receipt of the packet-based flush command, and then trigger a flush operation within the persistence domain to flush the one or more data items to the point of persistence. This provides a fast, hardware-based, mechanism for performing a flush operation within a persistence domain without needing to trigger software in the persistence domain to handle the flush to the point of persistence.