Patent ID: 7873733

Claim:
A load distribution device that receives processing requests from terminals and that allocates and transfers the processing requests to at least one of a plurality of servers, the load distribution device comprising: a monitoring unit monitoring communication data between each of the plurality of servers and the terminals or an operation state of each of the plurality of servers, a result of said monitoring including data indicating an amount of processing executed by each server receiving the processing requests from the terminals being stored in a recording unit; a request receiving unit receiving a request of an update preparation of the plurality of servers from a maintenance person terminal or an automatic update server; an update server determining unit determining a first non-updated server among the plurality of servers that includes a least amount of processing indicated by the data of the recording unit as a server to be updated and determining a second non-updated server other than the first non-updated server to be updated that includes a least amount of processing as a server to be updated next; a distribution ratio setting unit setting a distribution ratio of new processing requests for each of the plurality of servers so that the new processing requests from the terminals are not allocated to any of servers determined to be updated but to other servers and recording distribution ratios to the recording unit; a load distribution unit allocating and transferring the new processing requests from the terminals to at least one of the plurality of servers based on the distribution ratios; a notification unit notifying the maintenance person terminal or the automatic update server that a server to be updated is updatable based on the result of said monitoring including data in the recording unit; and an update completion detecting unit receiving a notification from the maintenance person terminal or the automatic update server that an update is completed, and wherein when the update completion detecting unit receives the notification, the update server determining unit determines that the update is completed, determines a new server to be updated and a new server to be updated next, and instructs the distribution ratio setting unit to set the distribution ratios.