Abstract: Disaster Recovery (DR) and High-Availability (HA) are a critical features required by many information technology systems. DR and HA may be accomplished with a remote secondary site that is kept synchronized with a primary site. To reduce the cost of maintaining a secondary site, the data may be split into two subsets wherein only a first subset of data is kept synchronized at the secondary site using a small bandwidth communication link. The second set of data, which is generally much larger, is periodically backed up at a network accessible back-up location. When a disaster occurs, the secondary site may access the most recent back-up of the second set of data. In a maintenance or limited failure situation, the secondary site can directly access the second data set at the primary site.

Abstract: Disaster Recovery (DR) and High-Availability (HA) are a critical features required by many information technology systems. DR and HA may be accomplished with a remote secondary site that is kept synchronized with a primary site. To reduce the cost of maintaining a secondary site, the data may be split into two subsets wherein only a first subset of data is kept synchronized at the secondary site using a small bandwidth communication link. The second set of data, which is generally much larger, is periodically backed up at a network accessible back-up location. When a disaster occurs, the secondary site may access the most recent back-up of the second set of data. In a maintenance or limited failure situation, the secondary site can directly access the second data set at the primary site.

Abstract: The special handling of multiple identical requests for the content during content caching is disclosed. A request for content, such as a web page request received from a client, is received. At least one of two actions is then performed. First, in response to determining that the content is cacheable and that a previous request for the content has already been forwarded to a server responsible for the content, such as a web server, the request is not processed until a response to the previous request is received. Second, in response to determining that the content is non-cacheable, the request is forwarded to the server responsible for the content.

Abstract: The special handling of multiple identical requests for the content during content caching is disclosed. A first for content, such as a web page request received from a client, is received. At least one of two actions is then performed. First, in response to determining that the content is cacheable and that a previous request for the content has already been forwarded to a server responsible for the content, such as a web server, the request is not processed until a response to the previous request is received. Second, in response to determining that the content is non-cacheable, the request is forwarded to the server responsible for the content.