A Pi-Powered Plan 9 Cluster

Re:A Pi-Powered Plan 9 Cluster by charlieo88 on Tuesday October 13, 2020 @09:53AM (#24765538)

Something that always bothers me about these Pi clusters is the Ethernet cable lengths. Isn't there a minimum length?

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Re:A Pi-Powered Plan 9 Cluster by dsr_ on Tuesday October 13, 2020 @10:02AM (#24765617)

10cm for 1000BASE-CX, nothing prior specified a minimum length.

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Re:A Pi-Powered Plan 9 Cluster by rwmj on Tuesday October 13, 2020 @10:09AM (#24765670)

That's really interesting - do you know why there is a minimum?

Maximum lengths are easy to understand because of voltage drops, interference and impedance over long distances. And of course in the old CSMA/CD days multiple senders couldn't be separated by too large a distance.

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Re:A Pi-Powered Plan 9 Cluster by MisterTea on Tuesday October 13, 2020 @10:30AM (#24765877)

signal reflection most likely. https://en.wikipedia.org/wiki/Signal_reflection

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