Patent ID: 7530073

Claim:
A method for extending the capacity of a federation of servers comprising at least two servers, wherein a first set of data in a first data structure is stored on a first server, and a backup of the first set of data in a first backup data structure is stored on a second server, said method comprising: adding a new server; creating a first temporary replication stream operable to replicate in the new server, during a move of the first backup data structure, any changes that are carried out on the first backup data structure as stored on the second server; moving the first backup data structure as stored on the second server to the new server by copying the first backup data structure from the second server to the new server while changes are being made to the first backup data structure as stored on the second server during the copying, the copying being performed by way of a copying stream separate from the first temporary replication stream, and by forwarding by way of the first temporary replication stream the changes to the first backup data structure as it is being copied to and stored on the new server; reconciling conflicts that arise between the first backup data structure as being copied to and stored on the new server and forwarded changes arriving at the new server by way of the first temporary replication stream, each conflict arising when an arriving change is with regard to a portion of the first backup data structure not already copied to and stored on the new server; creating a second data structure on the new server; and creating a second backup data structure for the second data structure on the second server.