Title of Invention

SYSTEM AND METHOD FOR PERFORMING A BACKUP OPERATION USING MULTIPLE DATA STREAMS

Abstract TITLE: SYSTEM AND METHOD FOR PERFORMING A BACKUP OPERATION USING MULTIPLE DATA STREAMS The invention relates to a method for performing a backup operation in a storage network, the method comprising receiving a first data stream having first data, the first data being obtained by a first application-specific data agent; receiving a second data stream having second data, the second data being obtained by a second application-specific data agent; multiplexing the first and second data streams to form a single stream of one or more data chunks of an archive file, including writing the first data from the first data stream and the second data from the second data stream into a first data chunk of the one or more data chunks; transmitting the one or more data chunks over a transport channel to a backup medium; and storing the one or more data chunks on the backup medium.
Full Text


SYSTEM AND METHOD FOR COMBINING DATA STREAMS IN
PIPELINED STORAGE OPERATIONS IN A STORAGE NETWORK
COPYRIGHT NOTICE
A portion of the disclosure of this patent document contains material
which is subject to copyright protection. The copyright owner has no objection to the
facsimile reproduction by anyone of the patent document or the patent disclosures, as it
appears in the Patent and Trademark Office patent files or records, but otherwise reserves
all copyright rights whatsoever.
RELATED APPLICATIONS
This application claims the benefit of U.S. provisional application no.
60/519,526 titled SYSTEM AND METHOD FOR PERFORMING PIPELINED
STORAGE OPERATIONS IN A STORAGE NETWORK, filed November 13,2003,
which application is incorporated herein by reference in its entirety.
This application is related to the following patents and pending
applications, each of which is hereby incorporated herein by reference in its entirety:
Application Serial No. _/ _, titled SYSTEM AND
METHOD FOR PROVIDING ENCRYPTION IN PIPELINED
STORAGE OPERATIONS IN A STORAGE NETWORK, filed
November 15, 2004, attorney docket number 4982/45;
U.S. Patent No. 6,418,478, titled PIPELINED HIGH SPEED
DATA TRANSFER MECHANISM, issued July 9, 2002, attorney
docket number 4982/6;
Application Serial No. 09/495,751, titled HIGH SPEED
TRANSFER MECHANISM, filed February 1,2000, attorney
docket number 4982/7US;

Application Serial No. 09/610,738, titled MODULAR BACKUP
AND RETRIEVAL SYSTEM USED IN CONJUNCTION WITH
A STORAGE AREA NETWORK, filed My 6,2000, attorney
docket number 4982/8;
Application Serial No. 09/744,268, titled LOGICAL VIEW AND
ACCESS TO PHYSICAL STORAGE IN MODULAR DATA
AND STORAGE MANAGEMENT SYSTEM, filed January 30,
2001, attorney docket number 4982/10;
Application Serial No. 10/65 8,095, titled DYNAMIC STORAGE
DEVICE POOLING IN A COMPUTER SYSTEM, filed
September 9, 2003, attorney docket number 4982/18; and
Application Serial No. 60/460,234, titled SYSTEM AND
METHOD FOR PERFORMING STORAGE OPERATIONS IN A
COMPUTER NETWORK, filed April 3,2003, attorney docket
number 4982/35PROV.
BACKGROUND
Backup operations for client data on a storage network are often performed
on streams of data which are managed by subclients and sent to a backup drive or media
device. Typically, on a given stream, only one sub client can perform a backup at any
given time. The concurrency limit for the number of backups that can go to a stream at
any given time is one. Indirectly this means that only one backup can be sent to a media
or drive at any point.
This limitation has a major drawback. With tape speeds in media
increasing and the difference between disk speed and tape speed widening, the tape

throughput is being throttled by the slower disks. This becomes a major issue in a large
enterprise where there are many clients with slow, under performing disks with large
amounts of data that need to be backed up in a fixed backup window. The only way the
backup window can be met is by backing up these clients, each to a different piece of
media in different drives. This increases the hardware requirement costs. This also can
create a "shoe shining" effect in which the tape is driven back and forth since drive
capacity is under-utilized at certain times.
Tape capacity is also growing and data from multiple clients can actually
fit on a single piece of media especially if the backup being performed is an incremental
backup. Scattering data across many pieces of media is a tape-handling nightmare for
backup administrators.
SUMMARY OF THE INVENTION
In accordance with embodiments of the invention, a method is provided
for performing a backup operation on a plurality of data streams containing data to be
backed up. In one embodiment, the method involves combining the data streams into a
single stream of one or more data chunks, including by writing data from more than one
of the data streams into at least one data chunk. The combining may be done by
multiplexing the data streams. The method further involves transmitting the one or more
data chunks over a transport channel to a backup medium and storing the one or more
data chunks on the backup medium..
Data from the data streams may be written into a data chunk until the data
chunk reaches a predetermined size, or until a configurable time interval has lapsed, or
otherwise in accordance with a storage policy as disclosed in some of the pending
applications referenced above, and as discussed herein.

During a restore operation or during an operation to create an auxiliary
backup copy, the data chunk is retrieved from the backup medium and data from the
separate data streams are separated from the data chunk. All data streams written into a
data chunk may be separated from each other into separate data stream portions. When
the data streams have been multiplexed, separating involves demultiplexing the data
streams written into the data chunk. The separated data streams may be restored to a
client or further stored as auxiliary copies of the data streams.
In some embodiments, the data streams contain data from a plurality of
archive files. Combining the data streams thus may involve writing data from more than
one archive files into at least one data chunk, and may further involve writing data from a
single archive file into more than one data chunk. In these embodiments, a plurality of
tag headers are inserted into the data chunk; each tag header describing data written in the
data chunk from a corresponding archive file. Data may be written into a data chunk until
the end of an archive file has been reached. When the data chunk is retrieved, from the
backup medium, the data from at least one of the archive files is separated from the data
chunk, or all the archive files may be separated into separate archive file portions, using
the tag headers when necessary to identify and describe the separate archive file portions.
The archive file portions may then be restored to a client or may be stored on an auxiliary
storage device which may be accessed in turn during a restore operation of a given
archive file requested by a client.
In accordance with some embodiments, the invention provides a system
for performing a backup operation on a plurality of data streams containing data to be
backed up. The system includes one or more receivers for receiving the data streams, a
multiplexer for combining the data streams into a combined data stream, a data writer for

writing data from the combined data stream portion of the combined data streams into one
or more data chunks, and one or more backup media for storing the one or more data
chunks. The system may further include a transport channel for transporting the data
chunks from the data writer to the backup media.
In accordance with further aspects of embodiments of the present
invention, a data structure is provided for a data chunk stored on a memory device. The
data chunk data structure is used by a computer system to backup data and includes a
plurality of portions of data from different archive files written into the data chunk from
multiplexed data streams containing the archive files and a plurality of tag headers each
describing one of the archive file portions written into the data chunk.
. BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 presents a block diagram of a network architecture for a system to
perform storage operations on electronic data in a computer network according to an
embodiment of the invention.
Fig. 2 presents a flow diagram of a system for multiplexing pipelined data
. according to an embodiment of the invention.
Fig. 3 presents a flow diagram of a system for multiplexing pipelined data
according to an embodiment of the invention.
Fig. 4 presents an exemplary current data format used prior to multiplexing
according to embodiments of the invention.
Fig. 5 presents an exemplary media format to support data multiplexing
according to embodiments of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention includes methods and systems operating in
conjunction with a modular storage system to enable computers on a network to share
storage devices on a physical and logical level. An exemplary modular stongs system is
the GALAXY™ backup and retrieval system and QiNetix™ storage management system
available from CommVault Systems of New Jersey. The modular architecture underlying
this system is described in the above referenced patent applications, each of winch is
incorporated herein.
Preferred embodiments of the invention are now described with reference
to the drawings. An embodiment of the system of the present invention is showin Fig. 1.
As shown, the system includes a client 85, a data agent 95, an information store 90,a
storage manager (or storage management component) 100, a jobs agent 102, a storage
manager index 107, one or more media management components (or media agent) IG;,
one or more media agent indexes 110, and one or more storage devices 115. Although
Fig. 1 depicts a system having two media agents 105, there may be one media agent 105,
or a plurality of media agents 105 providing communication between the client 85,
storage manager 100 and the storage devices 115. In addition, the system can include one
or a plurality of storage devices 115.
A client 85 can be any networked client 85 and preferably includes at least
one attached information store 90. The information store 90 may be any memory device
or local data storage device known in the art, such as a hard drive, CD-ROM drive, tape
drive, RAM, or other types of magnetic, optical, digital and/or analog local storage. In
some embodiments of the invention, the client 85 includes at least one data agent 95,
which is a software module that is generally responsible for performing storage
operations on data of a client 85 stored in information store 90 or other memory location.

Storage operations include, but are not limited to, creation, storage, retrieval, migration,
deletion, and tracking of primary or production volume data, secondary volume data,
primary copies, secondary copies, auxiliary copies, snapshot copies, backup copies,
incremental copies, differential copies, synthetic copies, HSM copies, archive copies,
Information Lifecycle Management ("ILM") copies, and other types of copies and
versions of electronic data. In some embodiments of the invention, the system provides at
least one, and typically a plurality of data agents 95 for each client, each data agent 95 is
intended to backup, migrate, and recover data associated with a different application. For
example, a client 85 may have different individual data agents 95 designed to handle
Microsoft Exchange data, Lotus Notes data,'Microsoft Windows file system data,
Microsoft Active Directory Objects data, and other types of data known in the art.
The storage manager 100 is generally a software, module or application
that coordinates and controls the system, for example, the storage manager 100 manages
and controls storage operations performed by the system. The storage manager 100
communicates with all components of the system including client 85, data agent 95,
media agent 105, and storage devices 115 to initiate and manage storage operations. The
storage manager 100 preferably has an index 107, further described herein, for storing
data related to storage operations. In general, the storage manager 100 communicates
with storage devices 115 via a media agent 105. In some embodiments, the storage
manager 100 communicates directly with the storage devices 115.
The system includes one or more media agent 105. The media agent 105
is generally a software module that conducts data, as directed by the storage manager 100,
between the client 85 and one or more storage devices 115, for example, a tape library, a
hard drive, a magnetic media storage device, an optical media storage device, or other

storage device. The media agent 105 is communicatively coupled with and controls the
storage device 115. For example, the media agent 105 might instruct a storage device
115 to perform a storage operation, e.g., archive, migrate, or restore application specific
data. The media agent 105 generally communicates with the storage device 115 via a
local bus such as a SCSI adaptor.
Each media agent 105 maintains an index cache 110 which stores index
data that the system generates during storage operations as further described herein. For
example, storage operations for Microsoft Exchange data generate index data. Media
management index data includes, for example, information regarding the location of the
stored data on a particular media, information regarding the content of the information
stored such as file names, sizes, creation dates, formats, application types, and other file-
related criteria, information regarding one or more clients associated with the information
stored, information regarding one or more storage policies, storage criteria, or storage
preferences associated with the information stored, compression information, retention-
related information, encryption-related information, stream-related information, and other
types of information. Index data thus provides the system with an efficient mechanism
for performing storage operations including locating user files for recovery operations
and for managing and tracking stored data.
The system generally maintains two copies of the media management
index data regarding particular stored data. A first copy is generally stored with the data
copied to a storage device 115. Thus, a tape may contain the stored data as well as index
information related to the stored data. In the event of a system restore, the index
information stored with the stored data can be used to rebuild a media agent index 110 or
other index useful in performing storage operations. In addition, the media agent 105 that

controls the storage operation also generally writes an additional copy of the index data to
its index cache 110. The data in the media agent index cache 110 is generally stored on
faster media, such as magnetic media, and is thus readily available to the system for use
in storage operations and other activities without having to be first retrieved from the
storage device 115.
The storage manager 100 also maintains an index cache 107. Storage
manager index data is used to indicate, track, and associate logical relationships and
associations between components of the system, user preferences, management tasks, and
other useful data. For example, the storage manager 100 might use its index cache 107 to
track logical associations between media agent 105 and storage devices 115. The storage
manager 100 may also use its index cache 107 to track the status of storage operations to
be performed, storage patterns associated with the system components such as media use,
storage growth, network bandwidth, service level agreement ("SLA") compliance levels,
data protection levels, storage policy information, storage criteria associated with user
preferences, retention criteria, storage operation preferences, and other storage-related
information.
A storage policy is generally a data structure or other information which
includes a set of preferences and other storage criteria for performing a storage operation.
The preferences and storage criteria may include, but are not limited to: a storage
location, relationships between system components, network pathway to utilize, retention
policies, data characteristics, compression or encryption requirements, preferred system
components to utilize in a storage operation, and other criteria relating to a storage
operation. A storage policy may be stored to a storage manager index, to archive media as

metadata for use in restore operations or other storage operations, or to other locations or
components of the system.
Index caches 107 and 110 typically reside on their corresponding storage
component's hard disk or other fixed storage device. For example, the jobs agent 102 of a
storage manager 100 may retrieve storage manager index 107 data regarding a storage
policy and storage operation to be performed or scheduled for a particular client 85. The
jobs agent 102, either directly or via another system module, communicates with the data
agent 95 at the client 85 regarding the storage operation. In some embodiments, the jobs
agent 102 also retrieves from the index cache 107 a storage policy associated with the
client 85 and uses information from the storage policy to communicate to the data agent
95 one or more media agents 105 associated with performing storage operations for that
particular client 85 as well as other information regarding the storage operation to be
performed such as retention criteria, encryption criteria, streaming criteria, etc. The data
agent 95 then packages or otherwise manipulates the client information stored in the
client information store 90 in accordance with the storage policy information and/or
according to a user preference, and communicates this client data to the appropriate media
agent(s) 100 for processing. The media agent(s) 105 store the data according to storage
preferences associated with the storage, policy including storing the generated index data
with the stored data, as well as storing a copy of the generated index data in the media
agent index cache 110.
In some embodiments, components of the system may reside and execute
on the same computer. In some embodiments, a client component such as a data agent
95, a media agent 105, or a storage manager 100 coordinates and directs local archiving,
migration, and retrieval application functions as further described in Application Serial

Number 09/610,738. These client components can function independently or together
with other similar client components.
Data and other information is transported throughout the system via
buffers and network pathways including, among others, a high-speed data transfer
mechanism, such as the CommVault DataPipe™, as further described in U.S. Patent No.
6,418,478 and Application No. 09/495,751, each of which is hereby incorporated herein
by reference in its entirety. Self describing tag headers are disclosed in these applications
wherein data is transferred between a flexible grouping of data transport modules each
supporting a separate function and leveraging buffers in a shared memory space. Thus, a
data transport module receives a chunk of data and decodes how the data should be
processed according to information contained in the chunk's header, and in some
embodiments, the chunk's trailer. U.S. Patent No. 6,418,478 and Application No.
09/495,751 generally address "logical data" transported via TCP/IP, however,
embodiments of the invention herein are also contemplated which are directed to
transporting, multiplexing, encrypting, and generally processing block level data as
disclosed, for example, in pending Application No. 10/803,542, titled Method And
System For Transferring Data In A Storage Operation, attorney docket number 4982/49,
which is hereby incorporated herein by reference in its entirety.
As discussed, these applications generally disclose systems and methods of
processing logical data. Thus, for example, contiguous blocks of data from a file might
be written on a first volume as blocks 1,2, 3,4, 5, etc. The operating system of the host
associated with the first volume would assist in packaging the data adding additional OS-
specific information to the chunks. Thus, when transported and stored on a second
volume, the blocks might be written to the second in a non-contiguous order such as

blocks 2,1, 5,3 , 4. On a restore storage operation, the blocks could (due to the OS-
specific information and other information) be restored to the first volume in contiguous
order, but there was no control over how the blocks were laid out or written to the second
volume. Incremental block level backups of file data was therefore extremely difficult if
not impossible in such a system since there was no discernable relationship between how
blocks were written on the first volume and how they were written on the second volume.
Thus, in some embodiments, the system supports transport and
incremental backups (and other storage operations) of block level data via a TCP/IP (and
other transport protocols) over a LAN, WAN, SAN, etc. Additional data is added to the
multi-tag header discussed in the applications referenced above which communicates how
each block was written on the first volume. Thus, for example, a header might contain a
file map of how the blocks were written on the first volume and the map could be used to
write the blocks in similar order on the second volume. In other embodiments, each
chunk header might contain a pointer or other similar data structure indicating the
chunk's position relative to other chunks in the file. Thus, when a file block or other
block changed on the first volume, the system could identify and update the
corresponding copy of the block located on the second volume and effectively perform an
incremental backup or other storage operation.
fn the system, for example as in the CommVault Galaxy system, archives
are grouped by Storage Policy. Many clients/sub clients can point to the same Storage
Policy. Each Storage Policy has a Primary copy and zero or more Secondary copies. Each
Copy has one or more streams related to the number of Drives in a Drive Pool.
The system uses a tape media to its maximum capacity and throughput by
multiplexing data from several clients onto the same media at the same time. The system

allows for a stream to be reserved more than once by different clients and have multiple
data movers write to this same piece of media.
During backup or other storage operations, data from a data agent to a '
media agent is transferred over a "Data pipeline" as further described herein and in U.S.
Patent No. 6,418,478 and Application No. 09/495,751. One or more transport processes
or modules, such as the Dsbackup in the CommVault Galaxy system, form the tail end on
the Media Agent for the pipeline. For example, in the Galaxy system, the Datamover
process running as part of Dsbackup is responsible for writing data to the media. For data
multiplexing, many such Data movers belonging to different pipelines have to write to the
same piece of media. This can be achieved by splitting the Datamover pipeline process
into multiple components including a data receiver, a data writer, and other modules as
necessary.
Fig. 2 presents a system for multiplexing pipelined data according to an
embodiment of the invention. As shown, Fig. 2 includes various data streams 125 in
communication with a transmit data pipeline 130 that includes one or more data receiver
modules 135, a multiplexing module 140, additional modules 145, and a data writer
module 150. Fig. 2 also includes a transport channel 155 from the transmit pipeline 130
to a receive pipeline 160 that includes a second receiver module 165 and other modules
170.
Backup streams 125 are fed into the transmit pipeline 130. For example,
in some embodiments, a backup process, such as the Dsbackup process in the
CommVault Galaxy system, packages file data and other data into chunks and
communicates the chunks via the backup streams 125. Thus, the transmit pipeline 130 or
tail end of the pipeline copies the data received in pipeline buffers from the backup

process via the backup data streams 125. A data receiver 135 processes the data received
from each backup stream 125. In some embodiments, there is one data receiver 135 per
backup stream 125, thus in the case of multiple backup streams 135, the system might
contain multiple data receiver modules 135.
A multiplexing module 140 combines the data received by the receiver
module(s) 135 into a single stream of chunks as further described herein. Thus, the
multiplexing module 140 may combine data from multiple archive files into a single
chunk. Additional modules 145 perform other operations on the chunks of data to be
transported such as encryption, compression, etc. as further described herein, in U.S.
Patent No. 6,418,478, pending Application No. 09/495,751, and pending Application No.
__/ , filed November 15,2004, attorney docket no. 4982/45.
The data writer module 150 communicates the chunks of data from the
transmit pipeline 130 over a transport channel 155 to the receive pipeline 160. The
transport channel may comprise a buffer, a bus, a fiber optic channel, a LAN, a SAN, a
WAN, a wireless communication medium, or other transport methods known in the art.
There is generally one data writer 150 per media (not shown) that receives data from
multiple data receivers 135 and writes data to the media. The data writer process 150 is
generally invoked when the first pipeline is established to use a given media and
generally remains running until all the pipelines backing up to this media are finished.
The data writer 150 writes the data to media or to the receive pipeline 160 and closes a
chunk when the chunk size is reached, the chunk size being a design parameter set to
allow only certain size chunks for transmission over the datapipe. In some embodiments,
the data writer 150 also updates the Archive Manager tables with the chunk information.
A multiplexed chunk thus will contain data from many archive files.

In some embodiments, the transmit pipeline receives data directly from the
system's data agents and writes multiplexed data to the media directly without an
intervening receive pipeline 160. Thus, in some embodiments, a single pipeline is also
contemplated. In embodiments that include both a transmit pipeline 130 and a receive
pipeline 160, the receive pipeline 160 processes data received from the transmit pipeline
130 for storage to media, etc. A second data receiver 165 processes data received from
the data writer 150 and additional modules 170 which may include encryption,
decryption, compression, decompression modules, etc. further process the data before it is
written to the storage media by a final data writer module (not shown).
In some embodiments, Data Multiplexing is a property of a Storage Policy.
Any storage policy with Data Multiplexing enabled has the ability to start backups for
multiple sub clients to run simultaneously to the same media. In some embodiments, a
resource manager process on the storage manager allows for multiple volume reservation
for media belonging to storage policies with data multiplexing enabled.
During a restore storage operation, the process is essentially reversed.
Data is retrieved from the storage media and passed back through the pipeline to the
original volume. Thus, during a restore, a data reader module (e.g. — a data receiver
directed to also retrieve data from storage) identifies the data by the looking into the tag
header of each retrieved chunk. Any offset into the chunk is a relative offset i.e. when
restoring data from a given archive file all the data buffers encountered from a different
archive file should not be counted into the offset calculation and should be thrown out.
Data within each volume block size of data will contain data from different Archive files.
The tag header also contains the archive file id. In addition, all the offsets stored are

relative offset within an archive file and does not depend on actual physical location on
the tape or other storage media.
A more detailed description of data multiplexing according to
embodiments of the invention is now described:
A single backup is made up of one or more archive files. An archive file is
made up of the smallest restorable component called the "Chunk". The chunk always
belonged to only one archive file. With data multiplexing a chunk interleaves pipeline
buffers from different pipelines. A tag header written for each buffer of data will uniquely
identify the data to the archive file. The tag header contains the archive file id (serial ID)
from the database corresponding to the archive file being backed up.
In some embodiments, for example in the CommVault Galaxy system, one
or more modules in the pipeline, such as the DsBackup module, package data or
otherwise retrieve data from a primary volume to be backed up and from the pipeline, and
sends the data to the DataMover or receive pipeline. DsBackup also initializes indexes
and updates the index cache every time it receives a file header from a client. DataMover
responsibility is to organize the data received from the dsBackup into chunks, start a new
chunk when the size of the chunk reaches the predetermined value, update the archive
manager tables information about the chunks and their location on that tape, also handle
end of media conditions and media reservations. DataMover uses the MediaFileSystem
object, for example I/O system API calls of a media agent or other system component, to
write data on to the tape and read data from the tape. MediaFileSystem has a Write buffer
and data is written onto the tape when this write buffer is filled with data.
With the new data Multiplexing model of DataMover, the previous
DataMover modules and their functionalities undergo changes.

Referring now to Fig. 3, consider clients CI, C2, C3 and C4 are backing
up at the same time and their data are getting multiplexed. DsBackup instantiates an
object of Data Receiver and initializes the object. Media is mounted as a part of the
initialization. One Data Writer object is instantiated for every media group Id.
Considering that all the four clients share the same media group id; only one Data Writer
object is instantiated and all the four Data Receiver objects share the same object to write
to the media.
Each Data Receiver writes a tag portion immediately by calling the Data
Writer's Write 0 method. Data Writer has an internal buffer, which is the same as the
selected block size. When this buffer is full, the buffer is locked and emptied to the
media. While this write operation is ongoing to the media, the second buffer will be ready
to accept data from the Data Receiver. The thread, which calls the write on Data Writer,
will return from the function call when the Media IO is complete. Meanwhile, the second
buffer fills. These double buffers are guarded with appropriate semaphores to ensure
proper concurrent access.
The Write operation is a blocking call and returns after completing the
write. The Data Writer Write API takes in the archive file id as the parameter and once
the write is completed, the physical offsets are updated in a list maintained by the Data
Writer object accordingly. When the size of the chunk exceeds the pre-determined size,
the chunk is automatically closed by writing a file mark, updating the archive manager
tables in the storage manager or at the media agent, and also updating the physical offsets
in the list or index maintained by the data writer object to track multiplexed storage files.
The Data Writer object is responsible for handling the end of media condition and the
Data Receiver does not generally require any knowledge about it.

As previously discussed, only the data writer object generally knows the
chunk closure, but there are conditions where the close chunk operation could be needed
because of a CLOSE ARCHIVE FILE message sent by the client. This means that the
system may need to close the chunk though the size of the chunk may not have reached
the predetermined size. When a CLOSE ARCHIVE FILE message is received from the
client, DsBackup calls into Data Receiver Close that in turn calls the Data Writer Close.
This close waits for a pre-determined amount of time for the chunk to get close on its own
as the other clients may be still pumping in data to the chunk. If after the pre-determined
time the chunk is not closed, the chunk is closed forcefully by writing a file mark and
updating the appropriate index cache. The only side effect this could result in is that the
chunk may not be as big as the pre-determined size as the close chunk has been force
fully done. The pre-determined time for wait can be made configurable or can be made a
variable parameter depending on the client type. With this new model there can be a
situation that the tag header gets split and is spanned between two data buffers on the
tape. This is generally addressed during the restore of data.
The following cases illustrate exemplary backup scenarios and
considerations according to embodiments of the invention:
1. Initialization of DataWriter. During the Initialization, the active media for the
media group is mounted. This method returns success only if the media is
mounted correctly. If the media is already mounted, this method just returns
success along with the volume Id of the mounted media. This may be required for
logging information for the Data Receiver in some embodiments.

- 2. CreateArchiveFile: In this method, an Archive file header is written on to the
media. This uses the special tag header which identifies the data in the tag portion
as an archive file header.
3. WriteToMedia: This method returns information to the upper layer if the write is
successful or not. Method returns information such as, end of the chunk, various
media errors, Media is full etc. There is no other way to indicate these conditions
other than as a return value in this method.
4. CloseArchiveFile: This method closes the archive file by writing an Archive file
trailer to the media. This again has a specialized tag header which identifies the
data as Archive file trailer. Close Archive file trailer does not return immediately,
There is a configurable time interval for which the writing to the current chunk
continues. The current chunk will be closed when all the archive files in this
chunk gets over or after the above time out interval from the first archive file close
request which comes in, whichever is the earliest.
There is generally no need of any call back methods to Data Receiver from
Data Writer. All communication from Data Writer to Receiver should be through return
values of the functions called in.
Restores of the multiplexed data are often less complicated since restores
are generally not multiplexed as the back-ups. But the aim during the restores is to seek to
the offsets and restore without looking into the tag headers in all of the data. Data Reader
object is instantiated during restore. The parameter for this object remains the same as the
current DataMover object. The client opens the required archive file by specifying the
archive file id. Then the client sends the seek offset. The Data Reader object queries the
archive manager to determine the chunk number that needs to be opened and the volume

that should be mounted to seek to the give offset. Once the media is mounted the media is
positioned to the correct file marker so as to open the chunk. Once the chunk header is
read and discarded, data is read block by block and the size of the block is the same as the
one that was used during the write. Every time a block of data is read all tag headers are
examined to determine whether it contains the data of the archive file that we are looking
for. This is done by traversing the buffer read in and looking through the tag headers. If it
contains any other archive file's data, that tag portion is discarded and the next header is
read. If the tag portion contains the data of the archive file that is being searched, then a
check is done to see if the tag portion contains the offset that is being searched. If it does
not contain the offset, this tag portion is skipped but the physical offset calculations are
incremented appropriately. Once the correct block that contains the offset is reached, the
data buffer pointer is positioned properly and the success is returned to the caller.
Once the seek is successful, a data reader/retriever module in the pipeline,
such as the FsRestoreHead module in the Galaxy system, requests a read with the read
size equal to the size of the tag header. The process looks into the tag header to
determine the size of the data that has to be read and requests a read with the size of the
data. The restore happens in this fashion. The Data reader will have a buffer more than
equal the size of one pipe line header as it may need to buffer the data during a read
request. The Data Reader also takes care of the case of tag headers that may have spanned
between two data blocks.
There is also metadata that is written on to the tape (or other media) during
back up to trouble shoot problems and also enable disaster recover programs, such as
CommVault's Dr-restore program which retrieves data from backups. During backup
every time a chunk is closed, a file marker is written. After this a data block is

constructed containing information, e.g., the list of archive file id's whose data is
contained in the recently closed chunk and their physical offsets and the size within this
chunk. A file marker follows this data and does not generally make any kind of update to
the database. In order to facilitate the disaster recovery tool functionality, we also indicate
which of the archive file ids were closed in the current chunk.
The data format on Media changes with Data Interleaving/Multiplexing.
An exemplary current data format and related data structures used prior to multiplexing
according to embodiments of the invention is shown in Fig. 4, and contains the following
fields and properties:
ArchiveFile Header
{
"ARCHIVE_FILE_HEADER_VERSION 2 \n "
"HeaderSize"
"Fileld"
"FileSeqNo""
"Streamld"
"ArchiveFileGroup "
"Agroupld "
"Copyld"
'AppId"
"Jobld"
"AppType"
"BackupLevel"
"BackupTime"
"FileType"
"SubAppType"
"ClientName "
"ArchiveFileName "
"GalaxyVersion"
"ARCfflVE_FrLE_HEADER_END 2"
}
ArchiveFile Trailer
{
"ARCH1VE_FILE_TRATLER_VERSI0N2 "
"TrailerSize "
"Fileld "
"FileSeqNo"

"Streaerld "
"ArchiveFileGroup "
"Agroupld "
"Copyld "
"Appld "
"Jobld "
"AppType "
"BackupLevel "
"BackupTime "
"FileType "
"SubAppType "
"ClientName "
"ArchiveFileName "
"GalaxyVersion "
"PhysicalFileSize "
"LogicalFileSize "
"ARCHIVE_FILE_TRAILER_END 2 ",
ChunkHeader
{
"CHUNK_HEADER_VERSION 2 "
"HeaderSize"
"Fileld"
"FileSeqNo"
"ChunkSeqNo"
"ChunkVol"
"ChunkVoIFM"
"TagHeaderOffset"
"CHUNIC_HEADER_END 2"
}
ChunkTrailer
{
"CHUNK__1TLAILER_VERSI0N 1"
"TrailerSize "
"Fileld"
"FileSeqNo"
"ChunkSeqNo"
"ChunkVol"
"ChunkVoIFM "
"ChunkLogicalSize "
"ChtmkPhysicalSize "
"CHUNK__TRAILER_END"

An exemplary media format to support data multiplexing according to
embodiments of the invention is shown in Fig. 5:
When data multiplexing is enabled, other elements of the previous system
also change in some embodiments as further described below. For example, Auxiliary
Copy currently copies data chunk by chunk within an Archive File. The assumption is
that the data within a chunk belongs to the same archive file. This is no longer true with
data multiplexing. In embodiments where data multiplexing is supported, Auxiliary Copy
allows two forms of copy mechanism: Simple Copy (copy whole chunk for all or part of
archive files) and De-Multiplexed copy (archive file by archive file; only if source is
magnetic).
In a simple copy, Auxiliary Copy creates a list of archive files that needs
to be copied and copies then chunk by chunk and volume by volume. Data from different
archive files will be copied at the same time to the secondary copy. This is faster, but the
resultant copy will have the data still interleaved as the original copy.
In a de-multiplexed copy, Auxiliary Copy will copy data archive file by
archive file. The result being that the system may go over the same set of media for each
archive file discarding data encountered from a different archive file. This approach is
slow and inefficient but the secondary copy has contiguous data for each archive file.
The system uses flags and other signaling mechanisms, for example flag
deMultiplexDataOnCopy on the ArchGroupCopy object, to dictate the choice of copy
mechanism. Archive Manager will pass down a list of Archive Files to be copied to the
secondary copy, if the copy is setup for a Simple Copy. If the DeMultiplexing is
supported on the Copy, AuxCopyMgr will pass down a single archive file to be copied.

Auxiliary Copy first creates all the headers for all archive files being
copied and then starts the copy. A set of messages will be sent over the pipeline for
creating these headers and in turn DSBackup will call DmReceiver create which will add
archive file information to the dmreceiverinfo structure maintained in Dm Writer. In
some embodiments, Auxiliary Copy also supports client based copies, where archive files
belonging for a set of clients will be copied. In other embodiments, a synthetic full
backup combines archive files backed up from a single sub client and creates a full
backup of all the incremental changes since the last full backup. The new archive file
being created as part of Synthetic full can be multiplexed with other backups.
Systems and modules described herein may comprise software, firmware,
hardware, or any combination(s) of software, firmware, or hardware suitable for the
purposes described herein. Software and other modules may reside on servers,
workstations, personal computers, computerized tablets, PDAs, and other devices suitable
for the purposes described herein. Software and other modules may be accessible via
local memory, via a network, via a browser or other application in an ASP context, or via
other means suitable for the purposes described herein. Data structures described herein
may comprise computer files, variables, programming arrays, programming structures, or
any electronic information storage schemes or methods, or any combinations thereof,
suitable for the purposes described herein. User interface elements described herein may
comprise elements from graphical user interfaces, command line interfaces, and other
interfaces suitable for the purposes described herein. Screenshots presented and
described herein can be displayed differently as known in the art to input, access, change,
manipulate, modify, alter, and work with information.

While the invention has been described and illustrated in connection with
preferred embodiments, many variations and modifications as will be evident to those
skilled in this art may be made without departing from the spirit and scope of the
invention, and the invention is thus not to be limited to the precise details of methodology
or construction set forth above as such variations and modification are intended to be
included within the scope of the invention.

APPENDIX A
Appendix A describes data structures, software modules, and other
elements of the system according to embodiments of the invention, such as in the
CommVault Galaxy system.
ArchChunkTable
table arch Chunk
(
id bigint, // 64 bit integer for unique chunk identification
commCellld integer,
volumeld integer,
fileMarkerNo integer,
createTime integer,
chunkVersion integer,
// INDEXES:
primary key (archChunkld),
foreign key (commCellld) references commCell(id),
foreign key (volumeld) references MMS2Volume(VolumeId),
);;
ArchChunkMapping table
Table archChunkMapping
(
archChunkld bigint,
archFileld integer,
commCellld integer,
archCopyld integer,
chunkerNumber integer,
physicalOffset bigint,
logicalOffset bigint,
physicalSize bigint,
logicalSize bigint,
primary key (archChunkld, archFileld, commCellld)
foreign key (archChunkld, commCellld) references archChunk (id, commCellld),
foreign key (archFileld, commCellld, archCopyld) references archFileCopy(archFileId,
commCellld, copy),

create table archGroupCopy
id serial,
archGroupId integer,
commCellld integer,
copy integer,
name varchar(MAX_DEFAULT_REC_SIZE,
MINJ3EFAULT_REC_SIZE),
compressionType integer,
flags integer,
maxMultiplex integer,
isActive integer,
type integer,
startTime integer,
waitForliDffline integer,
waitForlfBusy integer,
primary key (id, commCellld),
foreign key (archGroupId) references archGroup(id),
foreign key (commCellld) references commCell(id)
):
• Every Chunk has a Unique 64 bit id used as a counter to track chunks and perform
other functions
• Multiple archive file may be part of a single chunk
• The ArchChunkMapping table determines archive files contained in each chunk
• DmReceiver during restores queries archive manager and get the information for
the chunk required by providing the archive file id and the physical offsets.
• All data contained in a chunk belongs to the same copy.
• An integer value in the ArchGroupCopy table defines the multiplexing factor, and
determines how many clients can backup to this copy at the same time. This factor
is applicable for all streams within the copy.
• deMultiplexDataOnCopy flag indicates whether Auxiliary Copy should de-
multiplex data when creating a secondary copy. The flag on the secondary copy is
what is taken into consideration.
1.1.1 Creation of a Chunk
• DmWriter maintains a list of archive files that were written as part of the chunk
• When the chunk is closed, DmWriter makes a AMDS calls to close a chunk and
will pass along a list of archive files that made up the chunk
● Archive Manager creates the necessary entries in the ArchChunkMapping table
and the archChunk table entries

1.1.2 API's that changes in Archive Manager and AMDS
(1) ArchiveManagerDS: :getAfilelnfo(GetAf ileInfoArgs_t *
args, GetAfileInfoRet_t * ret)
Following structures defined in source/indude/ArMgr/AmdsArgs.h and CVABasic.h
change.
typedef struct {
unsigned long afileNumber;
unsigned long storagePolicyNumber;
unsigned long commCellld;
intt needArchChunkld;
} GetAfileInfoArgs_t;
typedef struct {
unsigned long afileNumber;
unsigned long agroupNumber;
unsigned long commCellld;
string name;
string objNamel;
string objName2;
unsigned long objVersion;
unsigned long numAppId;
unsigned long fileType;
unsigned long backupTime;
unsigned long seq;
unsigned long flags;
longlong__t createJobld;
unsigned long objType;
unsigned long backupLevel ,-
unsigned long isValid;
unsigned long streamNum;
ULONGrLONG firstChunkld;
} GetAfileInfoRet_t;
(2) int ArchiveManagerDS: :closeChunk(CloseChunkArgsDS t *
args, CloseChunkRetDS_t * ret)
Following structures defined in source/include/ArMgr/AmdsArgs.h and CVABasich
change:
struct CloseChunkArgsDS__t {
unsigned long commCellld;
unsigned long archCopyld;
ULONGLONG archChunkld;

int needNextArchChunkld;
unsigned long volumeId;
unsigned long fileMarkerNo;
unsigned long numberOfAfiles;
ChunkArchFileMsg_t *afileArray;
CloseChunkArgsDS_t() : needNextArchChunkld(0) {}
};
typedef struct {
ULONGLONG newChunkld;
} CloseChunkRetDS_t;
struct ChunkArchFileMsg_t {
unsigned long archFileld;
unsigned long chunkNumber;
u_longlong_t physicalOffset;
u__longlong_t logicalOf fset ;
u_longlong_t physicalSize;
u_longlong__t logicalSize;
};
typedef struct ArchiveFileId_t
{
unsigned long commCellld;
unsigned long agroupNumber;
unsigned long afileNumber;
} ArcMveFileld t;
1.2 Resource Manager
In previous versions of the system which did not support multiplexing, a
single Volume (defined by MMS2Volume table) could be reserved only once - the same
held true for drive reservations. This behavior changes to support data multiplexing. A
given volume can be reserved multiple times by different jobs for writes. The number of
times a volume can be reserved for writes is determined by the an index value, such as the
howManyCanMultiplex value set in the ArchGroupCopy table. The same stream also
now can be reserved multiple times due to this change.

commCellld integer,
archGroupId integer,
archGroupCopyld integer,
stream integer,
mediaGroupId integer,
isActive integer,
PreEmptable integer,
lastAfileldCopied integer,
howManyReservations integer, //Currently how
// many reservations
primary key (stream, commCellld, archGroupId, archGroupCopyld),
foreign key (commCellld) references commCell(id),
foreign key (archGroupId) references archGroup(id)
foreign key (mediaGroupId) references MMS2MediaGroup(MediaGroupId)
);;
table archStreamReserve
(
jobld LONGLONG,
priority integer,
reserveTime . TJME_T,
interruptJobld LONGLONG,
);
• Resource Manager allows up to "howManyCanMultiplex" number of
reservations on a volume, stream and drive when reservation type is "WRITE"
• Jobs running as part of a copy that support Multiplexing cannot generally be
interrupted
• These jobs can be suspended or killed
■ The Mark media full option is supported once per media group.
• Streams availability is no longer based on the "inuse" flag but on
"howManyReservations" field. If this value equals the "howManyCanMultiplex"
value for the ArchGroupCopy then that stream cannot generally be reserved.
• Resource Manager will reserve a specific drive.
• The selection of the drive is based on the volumeid and the mediaid set on the
drive table. If the requested media is already cache mounted in the drive and then
that drive is reserved.
• Resource Manager disallows any reservation of a client that wants to participate in
data multiplexing if the client has not been upgraded to support multiplexing.
1.3 Media manager
In previous versions of the system that did not support multiplexing, Media Manager
mounted a particular volume into any available drive and set the drive id in the

. reservation tables. This will change as now the reservation will be made for a specific
drive. When the mount request is received, Media Manager determines that the drive that
is reserved for this job and mounts the media into that drive. If the media is cache
mounted in a different drive then the reservation will be switched to that drive if that
drive is not reserved.
1.4 DSBackup
With data multiplexing data of different clients will belong to the same chunk and hence
each data block in the chunk has to be identified uniquely so as to perform the restore.
This will be achieved by storing the archive file id into the tag header that is associated
with every data block. The arch file id will uniquely identify the data block and the
database can be used to determine the client to which the data belongs. The structure of
an exemplary tag_header is given below.
typedef struct
{
char tag_magic[8]; // version of the tag. => Always use
// FILLTAGMAGIC to fill the tagjnagic
ULONGLONGblock_offset; // to be filled by client
// offset within archive
ULONGLONG blockjmmber; //filled by client - block no
// within afid
ULONGLONG functional_header_number; // sequence no of fun.header
unsigned long bufjype; // type of the buffer -
// MSB bit indicates data/functional
// header / PL_NAS_CMDS etc.
// 0-data 1 -functional header
unsigned long actual_block_size; // size of the data associated with
// this header
unsigned long compressed_block_size;// compressed size of the data
// associated with this header
unsigned long validity_bits; // flags
unsigned long buffer_validity; // invalid buffer
unsigned long data_offset; // offset of data within the block
unsigned long next_header_offset; // offset of next header. 0 means none
unsigned long compression_scheme; // scheme of compression to be applied

// 0 gzip
//111 (binary) no compression
unsigned char scatter_gather; // wont be used in vldb 98
// There are 3 extra bytes here for alignment
unsigned long compressed_data; // data is compressed y/n ? This filed is
// nolonger reliable because of a difference
on UNIX
unsigned char restore_backup; // data stream of backup=0,restore==l
unsigned char signature__dependency; // 0 not dependent on signature
//I dependent on signature
char spare[16 ];
}tag_header_t;
The field validity_bits has been renamed to archive_file_id to store the archive file as
shown below.
typedef struct
{
char tag_magic[8]; // version of the tag. -> Always use
// FILLTAGMAGIC to fill the tagjnagic
ULONGLONG block_offset; // to be filled by client.
// offset within archive
ULONGLONG block_number; // filled by client - block no
// within afid
ULONGLONG functional_header_number; // sequence no of fun.header
unsigned long bufjype; //type of the buffer -
// MSB bit indicates data/functional
// header / PL_NAS_CMDS etc.
// 0-data 1-functional header
unsigned long actual_block_size; // size of the data associated with
// this header
unsigned long compressed_bl°ck_size;// compressed size of the data
// associated with this header
unsigned long archive_file_id;
unsigned long buffer_yalidity; // invalid buffer
unsigned long data_offset; // offset of data within the block
unsigned long next_header_offset; // offset of next header. 0 means none
unsigned long compression_scheme; // scheme of compression to be applied
// 0 gzip
//111 (binary) no compression
unsigned char scatter_gather; // wont be used in vldb 98
// There are 3 extra bytes here for alignment
unsigned long compressed_data; // data is compressed y/n ? This filed is
// nolonger reliable because of a difference
on UNIX
unsigned char restore_backup; // data stream of backup=0,restore===l
unsigned char signature_dependency; // 0 not dependent on signature

// 1 dependent on signature
char spare[16];
}tag_headerj:;
The archive file id is filled "by the pipe layer of the client during backup. The tag header is
written on to the media in the same format without any modification. During restore Data
Reader reads the tag header to get find the archive file and in turn determine whether the
data associated with that restore is required for the current restore or not.
1.5 DataMover (Windows Implementation )
Datamover is responsible of writing the data transferred over the pipeline
to the media. With data multiplexing Datamover gets split into two components, Data
Receiver (DrnReceiver) and Data Writer (DmWriter). DsBackup invokes an instance of
DmReceiver object. The DrnReceiver object internally checks for the DmWriter's
existence for the requested MediaGroupId. If the DmWriter is not present then a new
instance of the DmWriter is created and cached in a DmWriter map. This map is
maintained in CVD's context of the media gent and is accessible to all DmReceiver.
DmWriter maintains an internal buffer corresponding to the volume block of the data per
DmReceiver. The volume block size is determined from the media type being used.
Write on the DmReceiver will call DmWriter write. DmWriter will copy the pipeline
buffers internally for aligning it to the volume block in the Receiverlnfo structure.
DataMoverBase class is the class that implements the functionality of DataWriter. Since
this class will be used for both backup and restore it was given a generic name
"DataMoverBase"

In the above classes, Data Receiver is a thin layer which in many cases calls the
DataWriter methods directly.

We Claim:
1. A method for performing a backup operation in a storage network, the
method comprising:
receiving a first data stream having first data, the first data being
obtained by a first application-specific data agent;
receiving a second data stream having second data, the second
data being obtained by a second application-specific data agent;
multiplexing the first and second data streams to form a single
stream of one or more data chunks of an archive file, including writing the
first data from the first data stream and the second data from the second
data stream into a first data chunk of the one or more data chunks;
transmitting the one or more data chunks over a transport channel
to a backup medium; and
storing the one or more data chunks on the backup medium.
2. The method as claimed in claim 1, wherein writing the first data and second
data comprises writing data from a single archive file into more than one data
chunk.

3. The method as claimed in claim 1, comprising inserting a plurality of tag
headers into the first data chunk, each tag header describing data written in the
data chunk from a corresponding data stream .
4. The method as claimed in claim 3, comprising writing data into a first data
chunk until the end of an archive file has been reached.
5. The method as claimed in claim 1, wherein when the first and second data
streams obtain data from a plurality of archive files, the method comprising
retrieving the first data chunk from the backup medium and separating data
from at least one of the archive files from one of the first and second data
streams of the first data chunk, wherein separating comprises demultiplexing the
data streams written into the first data chunk.
6. The method as claimed in claim 5, wherein the data from the archive files
written into the first data chunk is separated from each other into separate
archive file portions.
7. The method as claimed in claim 1, wherein forming a single stream of one or
more data chunks comprises writing data into the first data chunk until the first
data chunk reaches a predetermined size.

8. The method as claimed in claim 1, wherein forming a single stream of one or
more data chunks comprises writing data into the first data chunk until a
configurable time interval has lapsed.
9. The method as claimed in claim 1, wherein forming a single stream of one or
more data chunks comprises writing data into the first data chunk in accordance
with a storage policy.
10. The method as claimed in claim 1, wherein the data from all data streams
written into the first data chunk is separated from each other into separate data
stream portions.
11. The method as claimed in claim 1, wherein the first data and the second data
comprise different types of data, and wherein each of the first and second data
comprises at least one of the following types of data: migration data, snapshot
data, backup data and archive data.
12. The method as claimed in claim 1, wherein said receiving the first data
stream and receiving the second data stream comprise receiving the first and
second data in the same buffer.

13. The method as claimed in claim 1, wherein the first data is obtained from a
tape medium.
14. A system for performing a backup operation on a plurality of data streams
containing data to be backed up in a storage network, the system comprising:
a first agent module for obtaining first data, from a first application,
for transmission in a first data stream;
a second agent module for obtaining second data, from a second
application, for transmission in a second data stream, the second
application being different than the first application;
one or more receivers for receiving the first data stream and the
second data stream;
a multiplexer for combining the first and second data streams into
a combined data stream;
a data writer for writing data from the combined data stream
portion of the combined first and second data streams into one data
chunk, the data chunk having both first data from the first application and
second data from the second application; and
one or more backup media for storing the data chunk .

15. The system as claimed in claim 14, comprising a transport channel for
transporting the data chunk from the data writer to the backup media.
16. The system as claimed in claim 14, wherein the first agent module and the
data writer are part of the same local computing system such that the first data
stream is not transmitted over an area network.
17. The system as claimed in claim 16, wherein the first data stream is
transmitted via a bus.
18. The system as claimed in claim 14, wherein the first and second data
streams are from the same client computer.
TITLE: SYSTEM AND METHOD FOR PERFORMING A BACKUP OPERATION USING
MULTIPLE DATA STREAMS
The invention relates to a method for performing a backup operation in a storage
network, the method comprising receiving a first data stream having first data,
the first data being obtained by a first application-specific data agent; receiving a
second data stream having second data, the second data being obtained by a
second application-specific data agent; multiplexing the first and second data
streams to form a single stream of one or more data chunks of an archive file,
including writing the first data from the first data stream and the second data
from the second data stream into a first data chunk of the one or more data
chunks; transmitting the one or more data chunks over a transport channel to a
backup medium; and storing the one or more data chunks on the backup
medium.

Documents:

01625-kolnp-2006 abstract.pdf

01625-kolnp-2006 claims.pdf

01625-kolnp-2006 correspondence others.pdf

01625-kolnp-2006 description(complete).pdf

01625-kolnp-2006 drawings.pdf

01625-kolnp-2006 form-1.pdf

01625-kolnp-2006 form-2.pdf

01625-kolnp-2006 form-3.pdf

01625-kolnp-2006 form-5.pdf

01625-kolnp-2006 international publication.pdf

01625-kolnp-2006 other pct document.pdf

01625-kolnp-2006 pct form.pdf

01625-kolnp-2006 priority document.pdf

01625-kolnp-2006-correspondence others-1.1.pdf

01625-kolnp-2006-correspondence-1.1.pdf

01625-kolnp-2006-form-1-1.1.pdf

01625-kolnp-2006-form-18.pdf

01625-kolnp-2006-form-26.pdf

01625-kolnp-2006-international publication-1.1.pdf

01625-kolnp-2006-international search report-1.1.pdf

1625-KOLNP-2006-(20-01-2012)-CORRESPONDENCE.pdf

1625-KOLNP-2006-(28-12-2011)-ABSTRACT.pdf

1625-KOLNP-2006-(28-12-2011)-AMANDED CLAIMS.pdf

1625-KOLNP-2006-(28-12-2011)-CORRESPONDENCE.pdf

1625-KOLNP-2006-1-PETITION UNDER RULE 137.pdf

1625-KOLNP-2006-ABSTRACT-1.1.pdf

1625-KOLNP-2006-AMANDED CLAIMS.pdf

1625-KOLNP-2006-CORRESPONDENCE-1.1.pdf

1625-KOLNP-2006-CORRESPONDENCE-1.2.pdf

1625-KOLNP-2006-DESCRIPTION (COMPLETE)-1.1.pdf

1625-KOLNP-2006-DRAWINGS-1.1.pdf

1625-KOLNP-2006-EXAMINATION REPORT.pdf

1625-KOLNP-2006-FORM 1-1.1.pdf

1625-KOLNP-2006-FORM 18.pdf

1625-KOLNP-2006-FORM 2-1.1.pdf

1625-KOLNP-2006-FORM 26.pdf

1625-KOLNP-2006-FORM 3-1.1.pdf

1625-KOLNP-2006-FORM 3-1.2.pdf

1625-KOLNP-2006-FORM 3-1.3.pdf

1625-KOLNP-2006-FORM 5-1.1.pdf

1625-KOLNP-2006-FORM 5-1.2.pdf

1625-KOLNP-2006-GRANTED-ABSTRACT.pdf

1625-KOLNP-2006-GRANTED-CLAIMS.pdf

1625-KOLNP-2006-GRANTED-DESCRIPTION (COMPLETE).pdf

1625-KOLNP-2006-GRANTED-DRAWINGS.pdf

1625-KOLNP-2006-GRANTED-FORM 1.pdf

1625-KOLNP-2006-GRANTED-FORM 2.pdf

1625-KOLNP-2006-GRANTED-SPECIFICATION.pdf

1625-KOLNP-2006-OTHERS PCT FORM.pdf

1625-KOLNP-2006-OTHERS-1.1.pdf

1625-KOLNP-2006-OTHERS.pdf

1625-KOLNP-2006-PETITION UNDER RULE 137.pdf

1625-KOLNP-2006-REPLY TO EXAMINATION REPORT-1.1.pdf

1625-KOLNP-2006-REPLY TO EXAMINATION REPORT.pdf

abstract-01625-kolnp-2006.jpg


Patent Number 252239
Indian Patent Application Number 1625/KOLNP/2006
PG Journal Number 18/2012
Publication Date 04-May-2012
Grant Date 02-May-2012
Date of Filing 13-Jun-2006
Name of Patentee COMMVAULT SYSTEMS, INC.
Applicant Address TWO CRESCENT PLACE, OCEANPORT, NJ 07757-0090 USA
Inventors:
# Inventor's Name Inventor's Address
1 VIJAYAN RETNAMMA, MANOJ KUMAR 2140 ALDRIN ROAD OCEAN, NJ 07712
2 KOTTOMTHARAYIL, RAJIV 1508 GARDEN DRIVE OCEAN, NJ 07712
3 AMARENDRAN, ARUN PRASAD 2406 E BLOCK, JOTHY, Illam SAHAKARA, NAGAR, BELLARY ROAD BANGALORE 650092
PCT International Classification Number G06F; G06F
PCT International Application Number PCT/US04/038280
PCT International Filing date 2004-11-15
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/519,526 2003-11-13 U.S.A.