US Patent 9575978 Restoring objects in a client-server environment

Provided are a computer program product, system, and method for restoring objects in a client-server environment. An entry is added to an index for each chunk identifier. Each index entry includes one of the chunk identifiers and a reference to the chunk of data in the target storage from which the chunk identifier was calculated. A request is transmitted to a server recovery agent to recover an object from the storage server. Chunk identifiers of chunks of data in the requested object to recover are received from the server recovery agent. A determination is made from the index of whether the received chunk identifiers for the requested object matches the chunk identifiers indicated in the index. A request is made of the chunks from the server recovery agent for the received chunk identifiers not matching chunk identifiers in the index entries.