In the upload scenario where content is replicated to a remote site, the local server instance forwards a content transfer request to the remote server instance. The remote server is responsible for uploading the content that it receives to each of the selected replicas in its site. The following illustration shows this process, where both Site A and Site B are configured to use Content Platform Engine server communication. The object store exists in Site A, and it is configured with an advanced storage area. The advanced storage area is configured to use storage replicas in both Site A and Site B.
When users in Site A upload content to the Content Platform Engine servers in Site A, the servers write to the local replicas in Site A and perform a server-to-server content transfer to the remote Site B. Site B, in turn, writes the content to its replicas. Likewise, when users in Site B upload content to the Content Platform Engine servers in Site B, the servers write to the local replicas in Site B. They also perform a server-to-server content transfer to the remote Site A.
In Content Platform Engine server communication, the transfer of content is either synchronous or asynchronous, depending on the configured number of desired and required synchronous replicas on the advanced storage area.
Note that Content Platform Engine server communication:
Requires that the object store is configured with an advanced storage area, and that the advanced storage area is configured to use cross-site replicas. The virtual server in each site that is participating in the cross-site replication must be configured to use Content Platform Engine server communication.
The server communication URL that is specified for a virtual server can point to an HTTP server that load balances requests to the Content Platform Engine servers at that site. In this case, if SSL certificate validation is being performed, the SSL certificate of the HTTP server must be deployed to the SSL client Content Platform Engine servers.