Another unreachable Raspberry Pi3

Where do old GoPiGo3 Pi3 boards go when their WiFi dies? To become a desktop with a WiFi dongle, a fan, and uninterruptible power supply to run BOINC Einstein deep space data analysis, of course.

At least for a couple years - then like a deep space probe that suddenly goes quiet, I check on it and find it unreachable. The green light is blinking fine, and a cold boot doesn’t seem to restore connectivity. The WiFi dongle feels hot - not a good sign.

Can’t turn in packets without a network connection, and I don’t have an Ethernet switch at my desk.

Time to buy a few emergency WiFi dongles.

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Let us know what happens.

The cheapest ethernet switches are only ~$15 on Amazon, compared with ~$10 for the cheapest wifi usb adapters. I like to use ethernet because it takes out the uncertainty of the wifi connection. Unfortunately in my current home office I don’t actually have ethernet - I’m relying on wifi. So much less convenient.

The house we bought last year has Cat 5 throughout for phone wiring. I thought it would be easy enough to use for home networking. But I couldn’t find the cable that ran from near my cable modem to the basement, near my office. Tested every cable that terminated in the basement from the house. I may need to just break down and have a professional look at it.

/K

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This is puzzling behavior.  Unless something is overloading the USB interface chip, (you are using a USB dongle, right?), or the WiFi device isn’t the highest quality, I cannot understand what’s going on here.  Maybe the device itself has gone to that Big WiFi Graveyard In The Sky?

How close to your WiFi endpoint are you?  Can your device communicate effectively with the TX power turned down to something like 50% power?  Maybe a good-'ole Ham Radio hacking is needed, as in a small heat-sink on the transmitter module?  (You may wish to open up the defective unit and see what’s getting hot - and heat-sink the component on the next dongle.

Bit-rot (in the Pi) is a possibility, especially in the conspiracy laden air of Florida, (It’s ABSOLUTELY true that Space Aliens are deliberately shooting gamma rays at you to re-program your mind!  I heard it on the Internet, so it MUST be true!!  :wink:), so re-flashing the device’s firmware, including the GPU firmware, might fix the Pi itself.  You might want to heat-sink the WiFi chip on future Pi’s.

Probably the smartest $20/$50 you’ll ever spend is on a 8-port Ethernet switch on your desk or mounted somewhere nearby.  I have a 20 port rack mountable switch on a shelf and Cat-5 Ethernet wiring running all over the place hidden in plastic wiremold along the tops of the walls up against the ceiling molding where it blends right in.  WiFi has it’s place, but nothing beats pure copper for transmitting signals.

Let me know what happens.

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Absolutely. I think it was Yogi Berra who first said that. Or maybe Abraham Lincoln. :wink:
/K

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So here’s what happens:

  1. I ordered a 5-port Gigabit switch AND a new WiFi Dongle
  2. I was flightsimming into Palm Beach Intl this morning chasing some guy in a Cessna, and up pops
    “Your Internet Connection Does Not Support PhotoGrammetric Scenery - OK | Ignore”
    (The real reason I ordered the switch…simbox needs Ethernet not WiFi.)
  3. The switch and the WiFi Dongle arrive an hour later
  4. I put the new WiFi Dongle in DeskPi and fired it up - voila connected again.
  5. Thought WTH, plug in the old dongle and see if by magic it healed itself - voila ifconfig says its alive on the old WiFi IP. Sure enough. Put the new dongle on the shelf as a spare.
  6. Now to completely tear down my desk to add another power adapter to the two power strips, find a spot for the switch, and run cables to the Mac and the SimBox. (Pi computers can stay on WiFi - no serious traffic needs.)
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Don’t you just hate when that happens. Invariably you can never figure out what the issue was.

Good luck.
/K

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Interestingly, I just ran speedtest.net on my wired Mac and the WiFi’d SimBox. Wired Mac 476Mbit/s and WiFi’d SimBox 340Mbit/s … no slouch for Microsoft to be bad mouthing the connection.

Retest 417 vs 353. Even closer.

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Yeah - my current home office setup is wifi only. I just ran a speedtest - 367 Mbps down. Only 40 up, but good enough for WebEx which only needs 3 Mbps up for its best quality video.
/K

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I have seen that too, but it often flakes out:

  • A poorly shielded microwave nearby?

  • Someone else overlapping your channel?
     
    (Another wifi on your channel isn’t a problem as the two WiFi sources do a kind of negotiation to lower the impact.  A wifi source that’s nearby in frequency, such that it overlaps your channel, can really crush your throughput.  Set your active channel to 1, 6, or 11, (and 15 if available) as these channels are the ones that have full channels. Everything else overlaps.)&nbsp: Use 11 or 15 if it’s the last channel.  Use 5g instead of 2g if possible.
     
    Get Kewlsoft’s WIFI Analyzer app if possible.

  • An overheating wifi chip or controller?

Sometimes, if more than one device is demanding bandwidth, the connection will saturate.

I only use wifi for situations where bandwidth and throughput are not primary constraints.
(If possible)

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