Method for providing cable isolation in a fibre channel test environment

• US 20040073848A1
• Filed: 10/15/2002
• Published: 04/15/2004
• Est. Priority Date: 10/15/2002
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Pfeifer, Alan Thomas, Frazier, Darin Scott
• Granted Patent: US 7,007,204 B2
• Time in Patent Office: Days
• US Class Current: 714/43
• CPC Class Codes: G06F 11/221 to test buses, lines or interfaces, e.g. stuck-at or open line faults

Abstract

A cable isolator is provided for automatically performing cable breaks for testing of host bus adapters. A workstation includes a host bus adapter, such as a Fibre Channel storage controller, to be tested. The host bus adapter is connected to one or more storage modules through the cable isolator. The cable isolator includes two transceivers, one of which is connected to the host bus adapter and the other being connected to the storage modules. The two transceivers are also connected to each other internally. The cable isolator also includes a programmable logic device or controller that is used to enable and disable the two transceivers at set intervals. When the cable connection is to be broken, the programmable logic device generates one or more output disable signals. The one or more output disable signals are then provided to the transceivers to perform the cable break. An on-time and an off-time may be set using switches or dials.

Claims

1. A method for testing an ability of a host bus adapter to recover from a cable break, comprising:

a) providing a cable isolator connected between the host bus adapter and one or more storage devices, wherein the cable isolator includes a first transceiver connected to the host bus adapter and a second transceiver connected to the one or more storage devices;

b) receiving an on time value and an off time value;

c) automatically enabling at least one of the first transceiver and the second transceiver for an on time duration corresponding to the on time value; and

d) automatically disabling the at least one of the first transceiver and the second transceiver for an off time duration corresponding to the off time value.

2. The method of claim 1, further comprising:

repeating steps (c) and (d).

3. A method of using a cable isolator to test an ability of a host bus adapter to recover from a cable break, comprising:

connecting the host bus adapter to a first transceiver of a cable isolator;

connecting one or more storage devices to a second transceiver of the cable isolator;

setting an on time value;

setting an off time value; and

activating the cable isolator to automatically enable at least one of the first transceiver and the second transceiver for an on time duration corresponding to the on time value and automatically disable the at least one of the first transceiver and the second transceiver for an off time duration corresponding to the off time value.

4. The method of claim 3, wherein the step of setting an on time value includes setting an on time selector switch.

5. The method of claim 4, wherein the step of setting an on time value further includes setting an on time extension switch.

6. The method of claim 3, wherein the step of setting an off time value includes setting an off time selector switch.

7. A system for testing an ability of a host bus adapter to recover from a cable break, comprising:

a workstation computer including a host bus adapter to be tested; and

a cable isolator connected between the host bus adapter and one or more storage devices, wherein the cable isolator includes;

a first transceiver connected to the host bus adapter;

a second transceiver connected to the one or more storage devices;

an on time selector switch for setting an on time value;

an off time selector switch for setting an off time value; and

a controller, wherein the controller automatically enables at least one of the first transceiver and the second transceiver for an on time duration corresponding to the on time value and automatically disables the at least one of the first transceiver and the second transceiver for an off time duration corresponding to the off time value.

8. The system of claim 7, wherein the cable isolator further includes an on time extension switch for extending the on time value to form an extended on time value and wherein the controller automatically enables the at least one of the first transceiver and the second transceiver for an on time duration corresponding to the extended on time value.

9. The system of claim 7, wherein the first transceiver includes a first output disable pin and the second transceiver includes a second output disable pin.

10. The system of claim 9, wherein the controller enables at least one of the first transceiver and the second transceiver by deasserting at least one of the first output disable pin and the second output disable pin.

11. The system of claim 9, wherein the controller disables at least one of the first transceiver and the second transceiver by asserting at least one of the first output disable pin and the second output disable pin.

12. The system of claim 7, wherein the cable isolator further includes:

a communications adapter for receiving a first control signal; and

a first switch, wherein responsive to the first switch being closed, the controller enables or disables the first transceiver according to the first control signal.

13. The system of claim 12, wherein the communications adapter receives a second control signal, wherein the cable isolator further includes a second switch, and wherein responsive to the second switch being closed, the controller enables or disables the second transceiver according to the second control signal.

14. The system of claim 7, wherein the controller is a programmable logic device.

15. The system of claim 7, wherein the first transceiver and the second transceiver are small form factor pluggable transceivers.

16. A cable isolator connected between a host bus adapter and one or more storage devices, wherein the cable isolator comprises:

a first transceiver connected to the host bus adapter;

a second transceiver connected to the one or more storage devices;

an on time selector switch for setting an on time value;

an off time selector switch for setting an off time value; and

a controller, wherein the controller automatically enables at least one of the first transceiver and the second transceiver for an on time duration corresponding to the on time value and automatically disables the at least one of the first transceiver and the second transceiver for an off time duration corresponding to the off time value.

17. The cable isolator of claim 16, further comprising an on time extension switch for extending the on time value to form an extended on time value and wherein the controller automatically enables the at least one of the first transceiver and the second transceiver for an on time duration corresponding to the extended on time value.

18. The cable isolator of claim 16, wherein the first transceiver includes a first output disable pin and the second transceiver includes a second output disable pin.

19. The cable isolator of claim 18, wherein the controller enables at least one of the first transceiver and the second transceiver by deasserting at least one of the first output disable pin and the second output disable pin.

20. The cable isolator of claim 18, wherein the controller disables at least one of the first transceiver and the second transceiver by asserting at least one of the first output disable pin and the second output disable pin.

21. The cable isolator of claim 16, further comprising:

a communications adapter for receiving a first control signal; and

a first switch, wherein responsive to the first switch being closed, the controller enables or disables the first transceiver according to the first control signal.

22. The cable isolator of claim 21, further comprising:

a communications adapter for receiving a second control signal; and

a second switch, wherein responsive to the second switch being closed, the controller enables or disables the second transceiver according to the second control signal.

23. The cable isolator of claim 16, wherein the controller is a programmable logic device.

24. The cable isolator of claim 16, wherein the first transceiver and the second transceiver are small form factor pluggable transceivers.