How do I generate a bootstrap file on Ubuntu? I would like to generate a Bitcoin and Dogecoin (qt) bootstrap file on my ubuntu machine. Is there any way to do this? I know it's possible with Windows but I'm on Ubuntu.
Thanks.
Find your local blockchain:

cd ~/.bitcoin/blocks


Or, to bootstrap testnet, find your local testnet blockchain:

cd ~/.bitcoin/testnet3/blocks


Concatenate all your blkxxxxx.dat files and place the result in bootstrap.dat:

cat blk* &gt; bootstrap.dat


Warning: Using tar -cf (as instructed by this answer) did not work for me.  I'm importing from bitcoind into btcd.