Quote from: Taoman on February 20, 2017, 09:19:56 AM
The following was just posted on DSLreports:
QuoteMy Obi100 is seemingly flaky. It does not at all like to lose power, or perhaps sometimes to even reboot. It goes into the "flashing red light" mode which -- per some commentary on the Internet -- is unrecoverable. Its webpage will come up in recovery mode, and I can flash any firmware I chose, over and over, but it will still reboot flashing red.
I've discovered that it just wants a rest. I don't know why -- overheated components, maybe? -- but if I pull it from service for "some time" it will work just fine after I plug it back in. Most recently I'd set aside and was using instead my repurposed BasicTalk-branded HT701 with my Dockstar PBX and/or the Simonics GVGW. (Did that last Thanksgiving). But when the Obi200 went on sale this past weekend my wallet started to get itchy. Rather than jump to buy the new Obi I plugged in the old 100 and -- naturally -- it worked just fine.
I have been ridiculed on this forum before for making the same claim. But the experience of myself and so many others speaks for itself. A blinking red light indicates firmware corruption. It does not mean the device is "bricked."
If you simply disconnect a 100/110 series device from all connections and let it sit for a few days there is a good chance it will come back to life again and work reliably.
"Ridiculed"? Personally, I welcome your contributions. Let's just stick to basic principles of electronics and leave out the emotion.
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A blinking red light indicates firmware corruption.
That's true, but it doesn't cover every case of the blinking red LED. It's like the classic logic error, "all Greeks have beards, therefore, all men with beards are Greek."
If corrupted firmware was the root cause in this example, or the one on DSLReports, then how do you explain the "leave it unplugged and it magically works again"? The firmware can't fix itself. AFAIAK, DSLreports is the Breitbart News of the network tech world.
There are no large electrolytic capacitors inside the OBi, which would retain a charge over days. You can take the device apart and look, as I've done, if you are curious.
I've mentioned in the past, that it is more likely an example of
ESD damage to one or more of the integrated circuits in the device. It's common for ICs to break down over time, when exposed to repeated ESD or voltage spikes caused by disturbances on one of the external connections (phone line, power line, network cabling). Believe it or not, (tip of the hat to WelshPaul), cosmic rays can also cause gradual damage or momentary failures. That's why military-grade electronic equipment is built to more rugged standards, and has more rugged protection from these hazards. The OBi 1x0 devices contain a very inexpensive and simple flash memory module, which, BTW, has now been discontinued (end of life) by the manufacturer.
I don't know what the firmware subroutine is doing, when it checks and generates the red LED. To understand this, it's important to know that the OBis have a highly-integrated "system on a chip" or SOC, which contains a CPU and all the input/output circuitry. The SOC communicates with a separate, self-contained flash memory IC, which integrates the actual flash memory cells with an on-board flash controller. The SOC is talking to the flash module via a serial interface (sending commands and data back and forth, vs. directly controlling the flash memory cells). All the SOC can do is to use the command set and error messages supported by the flash memory module. The SOC is also using some form of checksum to determine if the firmware on the flash is good, or is corrupted. If the flash module returns an error code, or a bad checksum is calculated, then the SOC is going to decide to either quit and throw the permanent error (blinking red LED) or to retry.
A safe assumption in this case, is that the firmware tells the SOC to read from the flash memory IC, and the flash module returns either some high number of temporary errors, or a permanent error, or fails to respond at all. It's possible that the flash memory IC is teetering on failure, and will eventually crap out entirely, if additional electrical surge events occur. This is similar to the user experience when a computer's hard disk or SSD is starting to fail (in these cases, the drive controller's SMART firmware is monitoring for, and reporting on these errors).
I'm not arguing whether or not it's possible that a device can spontaneously stop throwing errors and work for some TBD amount of time. My view is simply that, if the thing fails and fails and fails, and I don't want it to fail again while I am using it for some important call, then I'd recycle it and buy a new one. Anyone who disagrees or doesn't care, is welcome to keep using their OBi.