Michael Ossman brings us the handiest little set of network administrator tools you can fit in your mini-screwdriver set. With one standard Ethernet cable, a straight-through coupler, and a few homebrew adapters, you will have:
straight-through ethernet cable:
crossover ethernet cable:
ethernet - coupler - crossover
DB9/RJ45 - ethernet - DB9/RJ45
null modem cable:
DB9/RJ45 - ethernet - coupler - crossover - DB9/RJ45
Cisco console cable:
DB9/RJ45 - ethernet - coupler - Cisco adapter
This set is easily expandable with a loopback (which will work on both Ethernet and RS-232, also useful for testing distant connectors) and one-way sniffers.
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