Cisco Technology, Inc.

Roy D'Cruz

Samar Sharma

Dinesh Ganapathy Dutt

Sanjaya Kumar

Prashant Billore

Jhaanaki M Krishnan

Ronak K Desai

Maurilio Cometto

Arindam Paul

Siva Ramineni

Thomas James Edsall

In one embodiment, a solution is provided wherein a volume hierarchy may be received at a network device in a storage area network. Once the network device is ready to apply the volume hierarchy, a message so indicating may be sent. Later, a command to apply the volume hierarchy may be received and the volume hierarchy may be applied so that the network device processes IOs using the volume hierarchy.

Volume hierarchy download in a storage area network

Disclosed is a data recovery mechanism associated with a data writing process in a storage area network (SAN). In general, a data writing mechanism is provided so that a particular host can write data to a storage device in a particular SAN session. One specific example of a data writing mechanism is a data tapping mechanism that provides a copy of this data to an appliance. The data recovery mechanism allows the appliance to recover data from the particular target, for example, when the data was unsuccessfully mirrored to the appliance during the data tapping or when the appliance needs to obtain the data that was written prior to a data tapping procedure being initiated. In one embodiment, the data recovery mechanism is set up so that the appliance can recover data from the target by mimicking the particular host.

Apparatus and methods for an appliance to recover data from a storage device

Disclosed is a session modification mechanism for altering a data tapping process in a storage area network (SAN). In general, a data tapping mechanism is set up so that an appliance receives SAN data that is tapped from a particular SAN session. That is, the data tapping mechanism provides to a particular appliance a copy of the SAN data that is being written from a particular host to a particular storage device. The session modification mechanism allows the appliance to alter various aspects of the SAN session that is to be (or is being) tapped. Examples of various modification features includes (i) redirecting READ commands initiated by the host to the appliance and not sending such command to the storage device, (ii) redirecting both READ and WRITE commands initiated by the host to the appliance and not sending such commands to the storage device, (iii) halting redirection and thereby causing READ commands initiated by the host to be sent to the storage device and WRITE commands initiated by the host to be mirrored to both the storage device and appliance, (iv) quiescing and unquiescing all data I/O's for the particular storage device and appliance, and (v) stopping and starting the data tapping mechanism.

Apparatus and methods for controlling a data tapping session in a storage area network

Disclosed is apparatus and methods for enabling an appliance to receive data being sent between any host of a host cluster to a specified storage device's logical unit (LUN) in a single stream or session. In one embodiment, a data virtual target is initially set up for a specified storage device LUN so that data written from a host to the specified storage device LUN is received by the DVT. An appliance then sends a session request to mirror data that is sent to the DVT (and specified storage device LUN) to a specified LUN of the appliance. The session request is not host specific. That is, data that is sent by any host to the DVT is mirrored to the same appliance LUN.

Apparatus and methods for facilitating data tapping with host clustering in a storage area network

Disclosed are methods and apparatus for data tapping within a storage area network (SAN) and providing tapped data to a third party device, such as an appliance. In general, mechanisms are provided in a SAN to allow a data tap of data flowing between an initiator and a target. In one implementation, a data virtual target (DVT) in created in a network device to intercept data sent by a specific initiator to a specific logical unit of a specific target. The data or a copy of the data is sent to both the specific logical unit of the specific target and to an appliance. The data routing may be accomplished by use of a virtual initiator (VI), which is configured to send the data (or a copy of the data) to the specific target and the appliance. In a transparent mode of operations, the DVT has a same PWWN (port world wide name) and FCID (fibre channel identifier) as the specific target. In a first proxy mode of operation, the DVT has a different PWWN and FCID than the specific target. In a second proxy mode of operation, the DVT has a same PWWN and different FCID than the specific target.

Growing community of inventors

Sunnyvale, CA, United States of America

Roy D'Cruz