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24

Since bitcoind/Bitcoin-qt 0.8, no transaction index is kept anymore by default, as it is not necessary for validation in the new database model. Instead, there is only a database of unspent transaction outputs, which has enough information to (slowly) locate transactions in block files. getrawtransaction uses this, but it only works for transactions that ...


17

Looks like you can get some here: https://onchain.io/bitcoin-testnet-faucet The term "faucet" has been used for quite some time for a site giving away small quantities of coins for free. If the above link ever stops working, a web search for "bitcoin testnet faucet" may find a different site.


14

After having installed Bitcoin core on your machine, run the following command to start synchronising the testnet blockchain bitcoind -testnet -daemon The synchronisation starts as a daemon and runs in the background, you can issue the following the command to see the progress tailf ~/.bitcoin/testnet3/debug.log To access the command line apis , just add ...


10

Have you tried understanding why you have that desire? It might help you understand more about what makes you tick. You might like to try mining Litecoins, or even on the Bitcoin Testnet. Or, you could try some Bitcoin mining with the Eligius pool, which from memory will pay out any amount after 2 weeks (whereas most pools have a minimum payout). If you can ...


10

Bitcoin doesn't use HTTP for its communications - it has its own specific protocol that runs directly on top of TCP. So an HTTP proxy like squid won't help. If you aren't able to make outgoing TCP connections through your firewall (mainly to destination port 8333) then you'll have to contact your corporate IT people about adding appropriate firewall ...


9

The current testnet is on its third iteration, somewhat unimaginatively titled testnet3. It was put that way by this commit: Testnet, Mark III gavinandresen authored 2012-04-12 Before that, we had testnet2: (though we didn't call it that back then) Reset testnet with a new genesis block davout authored 2011-02-03 Before that, testnet: ...


9

Testnet is really heavy (hundreds of gigabytes), there is a lighter alternative to that now: signet. There is also a local-only network called regtest, which I put in its own section. Finally, I'll explain txindex, which is a useful option to have your own mini block explorer. Signet To use it, first start bitcoind with the option: bitcoind -signet It will ...


8

Testnet bitcoins are less widely used in commerce than mainnet, and are not perceived as intended to be a currency. Yes, you're unlikely to fetch a significant price though. The transaction will not be recognized as a valid transaction. It would essentially be an irrelevant jumble. In fact the client wouldn't allow you to send anything because the address ...


8

You probably want to run multiple bitcoind instances in regtest to simulate multiple nodes. Thats pretty easy. You can run a second instance by starting bitcoind with a clean data directory and a different RPC and P2P port. For that, you could create a 2nd data directory (example: /tmp/datadir2). Create /tmp/datadir2/bitcoin.conf. Use something similar ...


8

Before version 0.16.0: $ bitcoin-cli getinfo { "version": 120100, "protocolversion": 70012, "walletversion": 60000, "balance": 0.00000000, "blocks": 414105, "timeoffset": -165, "connections": 9, "proxy": "", "difficulty": 199312067531.243, "testnet": false, "keypoololdest": 1466689642, "keypoolsize": 101, "paytxfee": 0.00000000, "...


8

Regtest is a network designed solely to be private and for testing only. You can create a private regtest network and do testing and experimentation with it. It is not a public network and has no peers for you to connect to.


8

Testnet has a built in functionality that changes the difficulty to 1 if the mining process takes 20 minutes or longer. This question explains the dropping of difficulty to 1. So while the difficulty is 1, the blocks are being formed rapidly until the difficulty reaches to a value which takes 10 minutes.


7

This rule is to prevent people from unintentionally spending Bitcoins that they wind up not owning. For any Bitcoins other than the block reward, unless you intentionally double spend, a reorganization leaves your transactions valid. So they can just be included in the new blocks. (Assuming they don't spend the proceeds of a double spend.) However, if ...


7

One more site to get free test bitcoins... http://kuttler.eu/bitcoin/btc/faucet/


7

Download Litecoin Core, install it, and start it with the -testnet option. I'm aware of two Litecoin testnet explorers: http://testnet.litecointools.com/ https://chain.so/testnet/ltc


7

You can run both at the same time: $ bitcoind -daemon $ bitcoind -testnet -daemon Then you can issue commands on either using: $ bitcoin-cli <commmand> or $ bitcoin-cli -testnet <command> The blockchains are stored in ./bitcoin/blocks for mainnet and /bitcoin/testnet3/blocks for testnet. Update: With the bitcoin.conf updated in the ...


7

That block is not just orphaned, it is actually invalid. It exploits CVE-2018-17144. The only way to fix this error is to upgrade to Bitcoin Core 0.16.3 and begin a reindex following the upgrade.


7

You can use Bitcoin Core's testmempoolaccept RPC. It will tell you whether the transaction you give it would be accepted into your node's mempool at that time but won't actually add it to the mempool or broadcast it.


7

The main difference between signet and regtest is that signet is an actual network, as opposed to a sandboxed environment. In regtest, the network topology is entirely manual. You spin up nodes, and manually establish connections between them. You have exact control over what blocks are mined and when. This is great for testing things like consensus logic, ...


7

You have two options to get set up on a Signet. One is to set up your own independent custom Signet that you can control. The other option is to use the default Signet set up and administered by Kalle Alm and AJ Towns. I will focus on the latter here. Currently as of the time of writing (August 2020) the Signet PR has been merged into Bitcoin Core, but is ...


6

www.blocktrail.com/tBTC now supports testnet too and has an API for it too (including wallet API)


6

I built a dedicated testnet wallet during a weekend hackathon http://testnetwallet.com


6

The path you pass to dumpwallet is the filename of the dump. If you pass the name of your wallet database itself (or any existing file, actually), it will get overwritten.


6

Depending on your OS you can start a 2nd bitcoin-qt acting on a non-mainnet with ./bitcoin-qt -testnet or ./bitcoin-qt -regtest (from a shell). You can also define a custom datadir and place a bitcoin.conf there (use bitcoin-qt -datadir=<path>). On OSX/Mac you would need to use Terminal and run something like /Applications/Bitcoin-Qt.app/Contents/...


6

The reason is not strictly the upgrade from 0.12 to 0.13, but from a version that does not support SegWit to one that does, after SegWit activated on the network. Bitcoin Core 0.13 comes with the code preparations for SegWit, although they are only enabled for testnet. Several miners have run pre-release code for 0.13 on testnet ahead of time, causing ...


6

The answer is no, you can't, because the two chains don't share a common history. Internally, transactions don't spend "from" an address. Instead, they refer to a specific output created by an earlier transaction which they consume. In order for a replay attack to work, that same transaction whose outputs are being spent must exist on both chains. This is ...


6

It seems you're mixing up bitcoind and bitcoin-cli. bitcoind is the Bitcoin Core daemon. It must be running first before you can do anything. bitcoin-cli is a tool to send RPC commands to a running bitcoind instance. From the linked documentation page: bitcoind -regtest -daemon No need to put a & after the command if you run with -daemon. Once ...


6

getinfo is now deprecated. Use getblockchaininfo instead: bitcoin-cli -testnet getblockchaininfo I don't have 50 reputation to comment. Otherwise, I would've added this as a comment.


6

The listunspent rpc call returns all unspent transaction outputs (UTXOs) tracked by this wallet. This includes the UTXOs that can be spent by this wallet, but also UTXOs that belong to watch-only addresses tracked by this wallet. When spendable is false, this wallet does not have the private key to spend the UTXO. This is e.g. the case for watch-only ...


6

Signet is more comparable to testnet than it is to regtest. Regtest is for private use and testing things. Even if signet were available, it is still useful to have your own blockchain for testing where you can generate coins, blocks, forks, and reorgs at will. It allows tests to run quickly and for a specific set of conditions to be tested. There is no ...


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