Mining against bitcoind stratum issues

[tom22022]

Thanks.  My linux bitcoind server is almost done syncing, will look into 0.19.1 when it finishes.  My question though would be how do mining pools do this?

Most of them probably don't rely completely on Bitcoin Core and builds the block using their own implementation. Most mining pool don't use GBT but stratum instead.

Unless you're able to see how the pool functions, you probably won't know if the problem exists for them and what their remedy is. Since the error exists due to the fact that they expect the coinbase flags, they can just add it at the end before feeding it to the miners.

When you say add it at the end, you mean compile it back in?

[NotATether]

When you say add it at the end, you mean compile it back in?

The PR mentions that the coinbaseflags was unused anyway so it must have had some default value set. So you'd either patch the RPC call in Bitcoin Core to return this key and value in the JSON or you paste whatever default value Core was using into cgminer code without fetching it from an RPC call.

If you ask me I'd say it's a lot easier to just fill in the missing value in cgminer.

[ranochigo]

When you say add it at the end, you mean compile it back in?

Yes. As GBT expects coinbase aux, you can just include it as an empty field again. It'll be easier to ensure minimal downtime as you won't have to waste your time to manage each of your mining instances. Alternatively, remove it from your mining client so it doesn't throw an error.

[tom22022]

When you say add it at the end, you mean compile it back in?

Yes. As GBT expects coinbase aux, you can just include it as an empty field again. It'll be easier to ensure minimal downtime as you won't have to waste your time to manage each of your mining instances. Alternatively, remove it from your mining client so it doesn't throw an error.

I guess this is where I am confused at, if I want to solo mine against bitcoind, which is the way to go if I don't want to downgrade to 0.19.1?  Add it back into the bitcoind code and recompile (not sure exactly how) --or-- remove code from miner client and recompile?

Thanks

[ranochigo]

I guess this is where I am confused at, if I want to solo mine against bitcoind, which is the way to go if I don't want to downgrade to 0.19.1?  Add it back into the bitcoind code and recompile (not sure exactly how) --or-- remove code from miner client and recompile?

Thanks

I wouldn't want to mess with Bitcoin codes if that is the case though I'm sure that they've only modified that part and didn't cause any issues otherwise.

I've found this awhile back: https://bitcointalk.org/index.php?topic=5322315.msg56584362#msg56584362. I didn't test his code but it makes the field optional. My solution for my own fork was to just remove it completely but the modification as referenced would work fine as well.

[tom22022]

Everyone on this post was so helpful I wanted to reach back out and let you know my solution which is subject to change by any other good advice I receive here.

I went out and bought a raspberry pi 4 with 8gigs and then bought the Argon One M.2 case that holds a SSD drive.  I bought the 1TB drive from Samsung.  Its a really neat tiny but powerful setup.  Then, I bought myself a Newpac USB miner based on the BM1387 chip.  Its running ubuntu.

I really had to do a lot of trial and error to get this all to work right.  I really like BFGMiner, but it will not work with the new Newpacs.  There was some posts about a year ago from @luke-jr about getting it supported but it doesn't have it yet.  The great features of BFGMiner from my point of view are the ability to use it as a stratum proxy for other miners as well as its ability to solo mine against the bitcoind higher versions.  But it just doesn't support the miner I use.

That's where cgminer comes in.  Cgminer is the only miner that supports the Newpac based on BM1387.  But, cgminer will not work for GBT solo mining against modern versions of bidcoind greater than 0.19.

So what I ended up doing is running my bfgminer as a stratum proxy and then run my cgminer with stratum+tcp and point it to the bfgminer.  Bingo works!

So that's my ugly setup!  I hope luke-jr reads this and decides to spend some time with the newpac drivers.