Nonce size - Will it always be big enough?
My question may be misphrased, if so, I'll correct it if you let me know in the comments.
My understanding of mining is that the header is appended with some
nonce and that is SHA256'd to get some hash, let's say:
This happens until there are X number of consecutive 0's in that hash. Is there a guarantee that there will always be at least X 0's in a row for every block header?