Re: why bitcoind started download bloks from the very begining?
Not likely, as individual block files are not interchangeable... my "blk01881.dat" file will not be identical to yours.
As above, did you move just the "blocks" or did you move everything including "chainstate"?
As above, did you move just the "blocks" or did you move everything including "chainstate"?
I copied everything
can you suggest, where I can read about how bitcoins works?
everything I found were about general principles, but I interested to learn how file bitcoins organised....
A bit here:
https://en.bitcoin.it/wiki/Data_directory
Some more info here:
https://bitcoin.org/en/developer-reference#block-chain
You said that the machine you had it on before is no longer working. How did it die?
In theory, once a block is written it should be good forever, but if there were hardware / OS issues and one or more of the block files got corrupted, even one from 6 years ago got corrupted it's going to re-download the entire chain.
-Dave