Update instructions to starting up regtest

[Steve12code]

Using Regtest mode as documented fails, you must first define rpcuser and rpcpassword before executing the generate 101 command.

[Steve12code]

Following the developer example I was unable to get the regtest option working without first populating bitcoin.conf. Altered doc to reflect this.

[harding]

@Steve12code this is already document near the top of the page:

Setting rpcuser shouldn't be necessary, so it isn't documented.

Would you consider it satisfactory for me to link to the above instructions from the testnet and regtest sections?

[Steve12code]

@harding a link back to the beginning and having the document mention it up there could work.

I do still have an issue when I don't specify rpcuser. I just took rpcuser out of the bitcoin.conf file and it has stopped working for me again. I am getting
"error: incorrect rpcuser or rpcpassword (authorization failed)"
and have to add it back in.

If that is not how things are supposed to work perhaps there is a specific order the tasks have to be done?

[harding]

@Steve12code if you start bitcoind with rpcuser set to a non-default value and then remove rpcuser from the config, it won't work. You have to shutdown bitcoind, remove the rpcuser setting, and then restart bitcoind. If that's what you did, can you let me know what version of Bitcoin Core you're using and what platform you're on?

I will add the links tomorrow. Thanks.

[Steve12code]

@harding

Thanks, doing that enabled me to get it functioning without rpcuser.

May I also ask what is the supported way of stopping bitcoind?
When I issue 'bitcoind stop' it refers me to utilize bitcoin-cli.
When I issue 'bitcoin-cli stop' I get 'error: couldn't connect to server'

I ended up doing this 'killall -9 bitcoind', which worked but I'm sure is not ideal.

[harding]

@Steve12code killall -9 bitcoind sends SIGKILL, which is a bad idea except if the daemon is not otherwise responding for a long time. If Bitcoin Core is forcibly shutdown in the middle of certain operations, you will need to reindex the entire block chain the next time you start---which can take hours.

If you must use kill or killall, try using it without the -9 to send SIGTERM. Bitcoin Core will handle this gracefully and shutdown correctly within a few seconds (maybe up to 30 seconds on a computer with really slow file system syncs).

If you started bitcoind with the same rpcpassword and (optional) rpcuser as are currently used in the bitcoin.conf, then using bitcoin-cli as the same user should work. As you said, the command bitcoin-cli stop should shutdown Bitcoin Core (again, this will take a few seconds).

I'm going to update the docs with the links in a few seconds and will close this pull when that's done. The website will be updated within 15 minutes after that. If you see any problems, you can continue commenting here.