Patent ID: 7209967
Filing Date: 2007-04-24
Classification: G06F,H04L

Abstract:
1. A network-attached storage (NAS) system including a housing and coupled to a plurality of clients via a network communication link over which the NAS receives client requests for access to files, the NAS system comprising: a first file server provided within the housing of the NAS system and including a first network interface, said first network interface having a first group of Internet Protocol (IP) addresses, said first group including one or more IP addresses; a second file server provided within the housing of the NAS system and including a second a network interface, said second network interface having a second group of Internet Protocol (IP) addresses, said second group including one or more IP addresses; and a storage unit provided within the housing of the NAS system and including a storage area of a first type that is assigned to the first file server and a storage area of a second type that is assigned to the second file server, the storage area of the first type including a plurality of file systems, each file system being associated with an IP address in said first group; wherein the storage area of the first type includes at least first, and second, and third file systems which are associated with first, second, and third IP addresses, respectively; the NAS system further comprising a system manager that communicates with the network communication link and the storage unit, and receives mapping information from the file systems for the associated IP addresses; wherein the first file server detaches the first file system and the first IP address which is associated with said first file system if it is determined that a workload of the first file server is heavy, so that the first file system could not be accessed by the first file server; and wherein said first file system is attached to the second file server and said first IP address is assigned to the second network interface, so that the first file system may be accessed via the second file server but not from the first file server.