Patent US5812751A successfully refreshed from Google Patents.
US5812751A
Expired / Lapsed
US
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Multi-server fault tolerance using in-band signalling
Assignee: QNAP Systems Inc
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Filing: 1997-10-03
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Granted: 1998-09-22
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Expires: 2017-10-03
Abstract
Abstract A primary server/standby server network configuration according to the invention includes a primary server executing network operating system software and a standby server monitoring for the proper operation of the primary server, where both the primary server and the standby server are connected to a storage system. If the primary server fails, the standby server instructs the storage system to switch its hardware connections to the standby server, allowing the standby server to boot the operating system. This instruction is done via in-band signaling. Further, multiple primary servers can be backed up by a single standby server.
Inventors
- 👤 Alexander C. Ekrot
- 👤 James H. Singer
- 👤 John M. Hemphill
- 👤 Jeffrey S. Autor
- 👤 William C. Galloway
- 👤 Dennis J. Alexander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:29
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/16; G06F11/20; G06F11/202; G06F11/2023; G06F11/2033; G06F11/2028; G06F11/2038; G06F11/2046; G06F13/00; G06F13/38; G06F13/40; G06F13/4004; G06F13/4022; G06F11/0703; G06F11/0751; G06F11/0754; G06F11/0757; G06F11/2002; G06F11/22
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
126 words
A method of operating a computing device in a standby mode, the method comprising the steps of: monitoring an input node of the computing device for a determination that the computing device must be transferred from the standby mode to an active mode; upon determining that the computing device must be transferred from the standby mode to an active mode, sending an indication to a storage system to cause the storage system to switch from communicating with a second computing device as a primary device to communicating with the computing device as the primary device, the indication being sent along a first signal line; receiving a boot program from the storage system along the first signal line; and booting the computing device in the active mode.
Claim 2
Independent Claim
126 words
A method of operating a computing device in a standby mode, the method comprising the steps of: monitoring an input node of the computing device for a determination that the computing device must be transferred from the standby mode to an active mode; upon determining that the computing device must be transferred from the standby mode to an active mode, sending an indication to a storage system to cause the storage system to switch from communicating with a second computing device as a primary device to communicating with the computing device as the primary device, the indication being sent along a first signal line; receiving a boot program from the storage system along the first signal line; and booting the computing device in the active mode.
Claim 3
Dependent Claim
12 words
The method of claim 1 wherein the computing device is a server.
Claim 4
Dependent Claim
41 words
The method of claim 1 wherein the monitoring step comprises monitoring the input node for periodic signals and upon failing to receive the period signals determining that the computing device must be transferred from the standby mode to an active mode.
Claim 5
Dependent Claim
47 words
The method of claim 1 wherein the computing device is coupled to a port of the storage unit, wherein the port includes signal lines for carrying signals according to a bus standard and wherein the first signal line comprises at least one signal line of the port.
Claim 6
Dependent Claim
12 words
The method of claim 4 wherein the port comprises a SCSI port.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein the step of sending an indication to a storage unit comprises sending a series of reset pulses.
Claim 8
Dependent Claim
15 words
The method of claim 6 wherein the series of reset pulses comprises eight sequential resets.
Claim 9
Dependent Claim
27 words
The method of claim 6 wherein the series of reset pulses are each of a predetermined length of time and are uninterrupted by any intervening busy pulses.
Claim 10
Dependent Claim
26 words
The method of claim 1 wherein the step of sending an indication to a storage unit comprises changing a voltage level on a terminator power line.
Claim 11
Dependent Claim
185 words
A computer-implemented process to control a server in a primary or standby mode, the process comprising the steps of: (1) determining whether the server is configured in a primary mode; (2) if the server is configured in a primary mode, performing the steps of: (a) determining the presence of a storage medium; (b) loading an operating system from a storage medium through a first port; and (c) booting the operating system; (3) if the server is not configured in a primary mode, performing the steps of: (a) initializing a timer; (b) monitoring an input node to determine the receipt of a heartbeat signal; (c) resetting the timer if the heartbeat signal is received; (d) initiating a switch command if the heartbeat signal is not received within a predetermined amount of time, the step of initiating a switch command including outputting a signal to the first port to cause the storage medium to switch the coupling of the storage medium from a failed server to the server; (e) loading the operating system from the storage medium through the first port; and (f) booting the operating system.
Claim 12
Dependent Claim
185 words
A computer-implemented process to control a server in a primary or standby mode, the process comprising the steps of: (1) determining whether the server is configured in a primary mode; (2) if the server is configured in a primary mode, performing the steps of: (a) determining the presence of a storage medium; (b) loading an operating system from a storage medium through a first port; and (c) booting the operating system; (3) if the server is not configured in a primary mode, performing the steps of: (a) initializing a timer; (b) monitoring an input node to determine the receipt of a heartbeat signal; (c) resetting the timer if the heartbeat signal is received; (d) initiating a switch command if the heartbeat signal is not received within a predetermined amount of time, the step of initiating a switch command including outputting a signal to the first port to cause the storage medium to switch the coupling of the storage medium from a failed server to the server; (e) loading the operating system from the storage medium through the first port; and (f) booting the operating system.
Claim 13
Dependent Claim
31 words
The process of claim 10 and further comprising the step of determining whether the server is configured for standby operation before determining whether the server is configured in a primary mode.
Claim 14
Dependent Claim
41 words
The process of claim 10 and, if the server is configured in the primary mode, performing the further steps of determining if the server is restarting from a non-graceful shutdown and if so indicating a desire to run a diagnostic program.
Claim 15
Dependent Claim
33 words
The process of claim 10 and, if the server is not configured in the primary mode, determining whether there is a cable fault at the input node prior to monitoring the input node.
Claim 16
Dependent Claim
41 words
The process of claim 10 and, if the server is not configured in the primary mode, further comprising the step of initiating the switch command upon receipt of a user input indicating that the user wishes to switch the server mode.
Claim 17
Dependent Claim
13 words
The process of claim 10 wherein the first port comprises a SCSI port.
Claim 18
Dependent Claim
23 words
The process of claim 10 wherein the step of outputting a signal to the first port comprises outputting a series of reset pulses.
Claim 19
Dependent Claim
15 words
The process of claim 16 wherein the series of reset pulses comprises eight sequential resets.
Claim 20
Dependent Claim
27 words
The process of claim 16 wherein the series of reset pulses are each of a predetermined length of time and are uninterrupted by any intervening busy pulses.
Claim 21
Dependent Claim
26 words
The method of claim 10 wherein the step of outputting a signal to the first port comprises changing a voltage level on a terminator power line.
Claim 22
Dependent Claim
229 words
A computer system comprising: a microprocessor; a memory array; a bus coupling the microprocessor to the memory array; a non-volatile memory device for storing a computer program which can be run by the computer system, the computer program encompassing a process to control the computer system in a primary or standby mode, the process comprising the steps of: (1) determining whether the computer system is configured in a primary mode; (2) if the computer system is configured in a primary mode, performing the steps of: (a) determining the presence of a storage medium; (b) loading an operating system from a storage medium through a first port; and (c) booting the operating system; (3) if the computer system is not configured in a primary mode, performing the steps of: (a) initializing a timer; (b) monitoring an input node to determine the receipt of a heartbeat signal; (c) resetting the timer if the heartbeat signal is received; (d) initiating a switch command if the heartbeat signal is not received within a predetermined amount of time, the step of initiating a switch command including outputting a signal to the first port to cause the storage medium to switch the coupling of the storage medium from a failed computer system to the computer system; (e) loading the operating system from the storage medium through the first port; and (f) booting the operating system.
Claim 23
Dependent Claim
229 words
A computer system comprising: a microprocessor; a memory array; a bus coupling the microprocessor to the memory array; a non-volatile memory device for storing a computer program which can be run by the computer system, the computer program encompassing a process to control the computer system in a primary or standby mode, the process comprising the steps of: (1) determining whether the computer system is configured in a primary mode; (2) if the computer system is configured in a primary mode, performing the steps of: (a) determining the presence of a storage medium; (b) loading an operating system from a storage medium through a first port; and (c) booting the operating system; (3) if the computer system is not configured in a primary mode, performing the steps of: (a) initializing a timer; (b) monitoring an input node to determine the receipt of a heartbeat signal; (c) resetting the timer if the heartbeat signal is received; (d) initiating a switch command if the heartbeat signal is not received within a predetermined amount of time, the step of initiating a switch command including outputting a signal to the first port to cause the storage medium to switch the coupling of the storage medium from a failed computer system to the computer system; (e) loading the operating system from the storage medium through the first port; and (f) booting the operating system.
Claim 24
Dependent Claim
15 words
The system of claim 20 wherein the non-volatile memory device comprises a read only memory.
Claim 25
Dependent Claim
14 words
The system of claim 21 wherein the non-volatile memory device comprises a flash EEPROM.
Claim 26
Dependent Claim
17 words
The system of claim 20 wherein the non-volatile memory device comprises a local boot drive or disk.
Claim 27
Dependent Claim
12 words
The system of claim 20 wherein the computer system comprises a server.
Claim 28
Dependent Claim
13 words
The system of claim 20 wherein the first port comprises a SCSI port.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-09-21 | 2002-03-23 | 2002-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-21 | 2006-03-23 | 2006-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-21 | 2010-03-23 | 2010-09-22 | $7700.00 | Window Closed / Lapsed |