Bitcoin Forum

I'm setting up a large number of D3s (I know, let's not have that conversation) and a large portion of them from one batch constantly reads Hardware:  Cannot Connect: Socket Connection Failed on the Status | Overview page.

It doesn't go away after FW reboots, replacing FW with Blissz, hours of running, multiple reboots, etc. I've tried APW++ PSUs on 110v, 208v and 240v - none work. I've increased and otherwise tweaked board voltage via Blissz FW. Nada. It's not uncommon to get this error for a few minutes on a new miner, but this never goes away.

Has anyone else encountered this? Any tips? I've tried everything on the Bitmain support page (not much) and it doesn't fix it. They haven't gotten back to my support requests yet...

Starting the thread in case anyone else has this problem. I'll post a solution when I find one.

99% of the time, the "Cannot Connect: Socket Connection Failed" message is due to incorrect pool configuration. Would you be willing to share your pool configuration info with us?

Thanks, but I checked that. The pool configuration is identical to the several working D3s I have. Cut and pasted between them.

In case anyone finds themselves in a similar position, here is what Bitmain advises:

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Dear L Lanaio,

Thank you for contacting us. The error message "Socket connection failed" has several possible causes. Please test as follows to determine the cause of the error on your miner:

Please upgrade the firmware: https://shop.bitmain.com/support.htm?pid=00720160617153633091CybeR3fo06DA

1. Confirm that your internet connection is stable. Network configurations or security settings in the router can cause this error.
2. If the network is good then please disconnect all the hash boards from both the power supply unit and the controller. Reboot the miner with only the controller connected. If the error still appears then we need to replace the controller. Please follow these instructions to create the ticket: https://bitmainhelp.zendesk.com/hc/en-us/articles/115000024827. Please reply with the ticket number and we will send a replacement.
3. If the error message does not appear with only the controller connected then please run the miner with one hash board at a time. If one of the hash boards is defective please create a repair ticket and return the hash board (for S9 return the whole miner) to us for repair: https://shop.bitmain.com/workOrderGuide.htm

Please let us know if the problem is still not resolved or you have further questions.

Best regards,
Barbara
Bitmain

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It looks like I got several bad controller boards.

I have had 10 machines do this to me at a time, a manual reset usually fixes it

Yeah, this was beyond the norm, It was bad IO boards. I followed Barbara's instructions and found that the board could not connect even with all hashboards boards disconnected. Then I went further and separated the BB boards from the IO boards and paired them up with boards from working units. BB boards worked, IO boards didn't. 27 bad ones! These things must have been built on a Monday, or whatever the Chinese equivalent is. It happens.

Both of mine miners went offline this morning. Due to socket connection failure. Do you guys know if it's possible to get a refund on them or they will just replace them?

Are you still in warrantee period? I doubt they'll refund them. (If so, please pass me that hammer.)  Also if they previously worked and now do not, I think they'll blame it on bad power or connectivity. Mine never connected from the moment I opened the boxes.

@llanaio

I wrote to them and they told me that I need to send the units back. I upgraded the firmware and everything is working. However when the miners reboot now and then the socket connection failure comes up again. Usually after a hard reset (unplug for 5-10 minutes) they connect again. Dont go at it with the hammer! Try resetting your router and internet settings. I think thats where the solution is, unless you wanna send them back to BITMAIN.