I was asked about how to use a rental here on Solo, and after much digging and watching the data packets between Craphash and the pool,
I discovered that the problem with doing that with ckpool, is that ckpool does the miner connection badly.
It always sends the pool default work difficulty before the miner validates their username/address and before sending the account difficulty setting.
For a miner this doesn't really matter, but for mining on Craphash, they look at the first work difficulty and thus wont allow it.
Clearly a certain person knew about this since it's his code, and he's had to allow Craphash mining on his solo pool, but he never bothered to fix the code.
Sooooo ... I ran some proxy rental runs using Craphash, since I guessed a proxy in front of the pool would work around this bug.
As mentioned in Discord on various occasions, while there are 2 KanoPool account types people can get: PPLNS and Solo, I have a 3rd account type called Override that gets no rewards, the shares are ignored when calculating rewards, but any blocks it finds goes to everyone on PPLNS.
i.e. live testing that has no negative effect on the miners, but a possible positive effect if it finds a block
I used about a 1 in 66 gamble in multiple runs, but alas no high enough share.
But anyway, the actual point of this post is to point out that Craphash steals between 2% and 3% of your BTC, so I don't suggest anyone should use them.
When you make an order, they take 3% as their start fee, however the actual amount of work you get, in all of the multiple runs I did, received between 2% and 3% less hashes than the 97% it should have.
You can of course work out what you should get quite simply.
If you are paying, say a high 0.0095 BTC/PH/Day and you use 0.2 BTC, then the amount of work you've paid for is:
0.97 * (0.2 / 0.0095) * 10^15 * (60 * 60 * 24) / (2^32) Diff
(3% fee) * BTC you paid * PH * 1Day / 1Diff
So in this case, 423.5G Diff
Alas you will find you will get less than 415G Diff (-2%)
Your worker will show these numbers if it's a new worker that starts at zero and you add :Diff + Invalid
(or write down what it was before you start mining the rental to it)
All pool, miner, proxy or accounting systems calculate hash rate from Diff, so they know how much Diff you are getting and use that to determine when to disconnect you.
They choose to disconnect you very much early between 2% and 3% early to be exact.
Oh well.