This morning I received an email from btcguild saying that one of my miners hasn't submitted shares for some time. This time it was KnC Juniper from October 2013 batch. I couldn't ping the miner, so I suspected a blown power supply. I went to the mining location and here is what I found:
1. Power supply unit is okay (HX1050), I measured all voltages with my multimeter, everything tested out fine
2. There is no problem with router or network anything, other miners run fine
3. The issue is with KnC miner itself, with BeagleBone to be exact.
I shut off the unit and after waiting for 30 seconds powered it back up. All I heard is a high pitch sound, coming from a control board. There was no LEDs on the board, all fans were spinning normally. I have an extra BBB, I swapped it and restarted the unit. Well, no high pitch sound this time and nothing was hashing of course. I went to get the recovery image off the KnC support site and was unable to use it!
Here are my questions:
1. Has anyone experienced anything similar to what I described?
2. It appears that KnC BBB and original BBB are very close to each other (KnC is missing USB port, power 5V plug, HDMI output). How do I get the image onto my BBB in when it happens again? In fact, there other reports that original BBB works with control board. (Instruction were the following: download .zip from support site, format flash as fat16 with boot flag and then unzip the recovery zip onto the root of the SD. Then, put the SD into the BBB, power up and hold USER/BOOT button for 3-5 seconds - that is when the flashing process should start with proper LED indication) - that doesn't happen at all. Any ideas?
3. Does KnC support has advanced RMA feature?
4. WTF?
Please advice.
P.S. It was a first major blow for KnC miner since October 18th 2013! Near perfect operation, 99.98% uptime!
I've had the same experience, modulo the high pitch sound, all the other sympthoms fit your descriptions. One thing that I noticed is that the only light coming from the machine was a fix blue one, it came from a led on the BBB.
Anyhow this is what I did (more or less the instrunctions that kncminer would send you in case you will ask):
1) Download and unzip the content of the
archive on to a micro SD card formatted with FAT file system.
2) Turn the miner off via the power supply off switch and disconnect from the wall.
3) Open the case of the miner.
4) Insert the micro SD with the recovery files on it in to the SD card slot on the controller board
Note: to insert the micro SD card into the slot it might be necessary to unplug the flat cables which connect the ASIC boards to the controller board.
5) Reconnect the power supply and turn the power on.
6) Please wait while internal MMC flash memory is reprogrammed there will be a sequence of LED as follows:
1,2,3,4 blue LEDs on the BeagleBone will turn on, then bright white LED inside the case turns on for several seconds and then the red + green LEDs on the control board are on this means that the programming is in progress. When only the green LED is on for 5 seconds this means that the recovery was successful then all LEDs should go off and it means that the procedure completed.
7) Turn the miner off again and disconnect from the wall.
Eject the micro SD card from the controller board.
9) Plug in all the cables that were unplugged and ensure that they are secured.
10) Reconnect the power supply and power on. The miner should then start from the on-board MMC flash with the software revision 0.96.1
After the miner is up and running again you can download the latest firmware version 0.99-tuning and apply the latest firmware.
