Stephen E Todd

US Patent:

6587959, Jul 1, 2003

Filed:

Jul 28, 1999

Appl. No.:

09/362270

Inventors:

Todd Michael Sjolander - Grafton MA
Stephen James Todd - Shrewsbury MA

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

H02H 305

US Classification:

714 4

Abstract:

A method of forwarding a message received by a server to a coupled hardware device in a server cluster where the server cluster is comprised of a default server and a coupled backup server. A look-up table is created in the server for all hardware devices coupled to the server by a server agent. The look-up table relates a unique identifier of a hardware device to a local path. The server agent sends all of the hardware identifiers to the client. Typically, this occurs as the result of a client application requesting this information. The client can then send a message for a hardware device connected to the server. The message is attached to a unique identifier which contains the hardware identifier. The server agent then extracts the identifier from the message. The server then retrieves the look-up table and locates the path in the look-up table for the coupled hardware device based on the hardware identifier parsed from the unique identifier.

US Patent:

6662241, Dec 9, 2003

Filed:

Sep 17, 1999

Appl. No.:

09/398269

Inventors:

Andreas Bauer - Acton MA
Todd Michael Sjolander - Grafton MA
Stephen James Todd - Shrewsbury MA
Kathleen R. Moxham - Hopkinton MA

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 300

US Classification:

710 8, 710 5, 710 10, 710104

Abstract:

A method and apparatus for controlling a peripheral device is provided. In a server, in a client/server environment, a server application receives a request for execution of a peripheral device script from a client application. The server application retrieves a peripheral device script which is associated with the request and the peripheral device script is passed to a script interpreter. The script interpreter converts the peripheral device script into at least one control signal. A device control module is coupled to the script interpreter and sends the control signal to the peripheral device. The device control module receives information signals from the peripheral device and forwards the information signals to the client application. The script may include code for configuring the peripheral device, code for requesting information about the peripheral device or code for controlling the peripheral device.

US Patent:

6711574, Mar 23, 2004

Filed:

Feb 1, 2000

Appl. No.:

09/496308

Inventors:

Stephen Todd - Shrewsbury MA
Andy Kubicki - Westborough MA
Michel Fisher - Natick MA

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 1730

US Classification:

707100

Abstract:

A system and method of retrieving management information in a protocol environment having a maximum retrieval byte size is provided. An example of such a protocol environment is SCSI environment. A retrieval command is sent from an initiator to a target where the retrieval command is capable of retrieving more information than the maximum allowed by the protocol. A target buffer is created at the target in response to the retrieval command and the target buffer is filled with management information associated with the target. The management information may be in the form of mode pages when the method is applied in a SCSI environment. The management information is then sent from the target buffer to the initiator. If all of the management information is not retrieved, a second retrieval command is sent by the initiator to retrieve at least a portion of the unsent management information.

US Patent:

6742059, May 25, 2004

Filed:

Feb 4, 2000

Appl. No.:

09/498287

Inventors:

Stephen Todd - Shrewsbury MA
Andreas Bauer - Acton MA
David Kurt Spencer - Northborough MA
Walter T. Dobberpuhl - Milford MA

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 300

US Classification:

710 19, 709219, 709224, 710 15

Abstract:

There is disclosed a client-server configuration including a peripheral device wherein multiple servers interface with both the client and the peripheral. Management software for determining the operating state of the peripheral, known as server agent software, is employed in the multiple servers under control of the client. In order to avoid conflicting information reflecting multiple operating states of the peripheral, a primary/secondary algorithm is used to enable the client to determine only one peripheral operating state while allowing each server to also verify its connectivity to the peripheral and to the client.

US Patent:

6754718, Jun 22, 2004

Filed:

May 10, 2000

Appl. No.:

09/568386

Inventors:

Walter T. Dobberpuhl - Milford MA
Andreas L. Bauer - Acton MA
George M. Ericson - Shrewsbury MA
Charles H. Hopkins - Upton MA
Jennifer Lyn Milliken Nicoletti - Framingham MA
Timothy D. Sykes - Berlin MA
Stephen James Todd - Shrewsbury MA

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 1516

US Classification:

709250, 709213, 709227, 707200

Abstract:

A method apparatus and computer program product for providing access to host attribute information in a storage area network is disclosed. The storage area network is composed of a plurality of hosts coupled to at least one initiator. Each initiator is coupled to one or more targets and each initiator has an associated identifier. In each host, the identifier of the initiator is related to other host attribute information. The identifier may be, for example, a world wide name. The host attribute information including the identifier is sent from each of the plurality of hosts to the one or more targets and stored in memory of an associated storage array. Either a host or requestor remote from the storage array may request the collected host attribute information from the storage array. A topology of the storage area network may then be formed from the host attribute information of each host.

US Patent:

7076690, Jul 11, 2006

Filed:

Apr 15, 2002

Appl. No.:

10/122556

Inventors:

Stephen J. Todd - Shrewsbury MA, US
Matthew J. D'Errico - Southborough MA, US
Steven Blumenau - Holliston MA, US

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 11/00

US Classification:

714 13, 714 5, 714 6

Abstract:

One embodiment is directed to a method in a computer system including a host computer and at least one storage system including first and second storage volumes, the host computer including at least one application program executing thereon. The method comprises acts of intercepting and redirecting an access request from the at least one application program to the first storage volume to the second storage volume. Other embodiments are directed to a computer readable medium with instructions for performing the method, a host computer with at least one controller to intercept and redirect the access request. Other aspects are directed to methods in a computer system including a host computer, a first storage system including a first storage volume, and a second storage system including a second storage volume, wherein the second storage volume is a hardware mirror of the first storage volume. One method comprises an act of servicing a read request to the second storage volume while maintaining the second storage volume as an active hardware mirror of the first storage volume. Another method comprises an act of, in response to a failure preventing access from the host computer to the first storage volume, servicing access requests directed to the first storage volume from the second storage volume without reconfiguring the host computer.

US Patent:

7080221, Jul 18, 2006

Filed:

Apr 23, 2003

Appl. No.:

10/421401

Inventors:

Stephen J. Todd - Shrewsbury MA, US
Steven M. Blumenau - Holliston MA, US
Zoran Cakeljic - Newton MA, US
Donagh Buckley - Co. Cork, IE
Conor Fox - Co. Cork, IE
John Philip Bell, II - Clonakilty, IE

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 13/00

US Classification:

711161, 711162, 711165, 707201, 707202, 707203, 707204, 714 6

Abstract:

Methods and apparatus for performing a data migration in a clustered computer system. In one aspect, the availability of the data being migrated is maintained during the migration. In another aspect, a data set is migrated by a transfer utility in one of the hosts in the cluster, and in response to a failure of the host, the migration is resumed without restarting from the beginning point of the data set. In a further embodiment, the hosts in the cluster have agents associated therewith to manage the data migration, and prior to taking at least one action associated with the data migration, the agents coordinate to ensure that the hosts in the cluster are prepared to have the at least one action taken.

US Patent:

7080225, Jul 18, 2006

Filed:

Dec 10, 2002

Appl. No.:

10/315472

Inventors:

Stephen J. Todd - Shrewsbury MA, US

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 12/00

US Classification:

711165, 711 5, 711 6, 711154, 711161, 711162

Abstract:

Methods and apparatus for migrating a data set. In one embodiment, a migration is paused. In another embodiment, for a migration of data between multiple source/target groups, the migration is initiated by beginning transfer for some groups and queuing others for later processing. In a further embodiment, different transfer vehicles are used for different source/target groups. In a still further embodiment, a transfer vehicle is automatically selected for at least one source/target group.