Troubleshooting Hubs with Crossover Cable
A crossover cable can be used to identify the type of failure when hub performance or connectivity is in question.
1Connect a file server and a client PC back to back with a crossover cable to verify that the NIC and network operating system are properly configured.
2To make a crossover cable, connect TD+ to RD+ and TD– to
The cable performs the crossover that is usually performed by the hub. Figure
crossover cable:
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1 |
| 1 | TD+ 1 | 1 | TD+ | |
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2 |
| 2 | TD | 2 | 2 | TD |
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3 |
| 3 | RD+ 3 | 3 | RD+ | |
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4 |
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| 4 | 4 |
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5 |
| 5 | RD | 5 | 5 | RD |
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6 |
| 6 | 6 | 6 | ||
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| 7 | 7 |
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8 |
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| 8 | 8 |
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Figure C-1 Straight-through and Crossover Cable Pinouts
If the file server and client PC function together as a small network, then either the existing cabling or the hub is failing.
When a crossover cable is used, the LED on the NIC functions differently than it would under normal operating conditions. For example, with a correct crossover connection, the LED lights, whereas with a