Abstract: Techniques to achieve high availability in a multi-controller system are disclosed. In various embodiments, an indication is received that a network ping-based heartbeat mechanism has failed. In response to said indication, an alternative heartbeat is provided at least in part by periodically updating a heartbeat data stored in an on-disk heartbeat data structure, in a portion of a disk that is available to both an active controller and a standby controller of the multi-controller system.

Abstract: In a network where there are two local area networks (LANs) connected over a wide area network (WAN) by paralleled LAN to WAN devices at each end of the WAN, Transmission Control Protocol (TCP) connections may be requested by a first near end LAN to WAN device and received at a first far end LAN to WAN device but the acknowledgement may be returned to a second far end LAN to WAN device. The second far end LAN to WAN device contacts the first far end LAN to WAN device and the TCP connection is moved to the second far end LAN to WAN device, which provides the acknowledgement to the first near end LAN to WAN device to complete the TCP connection. Similar operations occur during active TCP connection operation but with certain queued data being flushed during the TCP connection transfer.

Abstract: In one embodiment, a system and method for managing a network deduplication dictionary is disclosed. According to the method, the dictionary is divided between available deduplication engines (DDE) in deduplication devices that support shared dictionaries. The fingerprints are distributed to different DDEs based on a hash function. The hash function takes the fingerprint and hashes it and based on the hash result, it selects one of the DDEs. The hash function could select a few bits from the fingerprint and use those bits to select a DDE.

Abstract: In one embodiment, a system and method for managing a network deduplication dictionary is disclosed. According to the method, the dictionary is divided between available deduplication engines (DDE) in deduplication devices that support shared dictionaries. The fingerprints are distributed to different DDEs based on a hash function. The hash function takes the fingerprint and hashes it and based on the hash result, it selects one of the DDEs. The hash function could select a few bits from the fingerprint and use those bits to select a DDE.

Abstract: TCP connections are moved between parallel devices and links during either connection setup or during active operation.