Remote Client Option

The Remote Client option lets client applications running on a networked Web or application server connect to a remote SOSS store. In some situations, it may be advantageous to run ScaleOut StateServer on a separate server farm that is networked to a Web or application server farm. This approach lets you provision the SOSS farm with the dedicated CPU, memory, and networking resources required to handle the largest possible storage loads. It also offloads SOSS’s use of these resources from your Web and application server farm.

A remote client first attempts to connect to one of the gateway addresses listed in the soss_client_params.txt client parameters file (see Configuration Parameters). It will connect to the remote store if any of the gateway addresses responds. To maximize the opportunity to connect to the remote store, the client parameters file should be populated with gateway addresses associated with all hosts in the store. This can be accomplished using the Populate command in the Management Console or the soss.exe command-line management tool (see Command-line Control Programs).

To maximize scalability and high availability, every remote client directly connects to all servers in the remote store, as shown in the following diagram:

images/diagrams/remcli_diagram2.png

The remote client obtains dynamic load-balancing information from the remote SOSS store and automatically updates this information as the load-balance changes. To minimize response times, the client uses this information to direct access requests directly to the host which holds the requested object. If the host becomes unavailable, the client automatically redirects the request to another host in the store. Multiple applications running at the remote client can independently and concurrently access hosts within the SOSS store.

The management tools also use the remote client libraries to connect to the remote SOSS store. To balance the management load, an initial connection is made to a random host within the store. If that host is unavailable, repeated attempts are made to connect to another host using the gateway list in the client parameters file.

Once a connection is established to a host with the SOSS store, management operations then proceed as if the user were locally connected to that host. The connected host is displayed as the local host by the management tools. If the host should become unavailable, the management tools automatically attempt to connect to another host in the store.