A complete beginners guide to installing a Bitcoin Full
A complete beginners guide to installing a Bitcoin Full
Python3 Qt5 (PyQt5) Tutorial | DevDungeon
Running A Full Node - Bitcoin
How To Install Bitcoin Core on Ubuntu – Linux Hint
Bitcoind – Commands, RPC Protocol, Install Server
A Guide to Keeping Keys Offline Using Armory +rPi
Hi Redditors. I am going to post in this thread my experiences in getting my Desktop (Debian) machine running Armory in watch-only mode, and coupling that with an offline Raspberry Pi (which holds my private keys) for signing the transactions previously made in watch-only mode. I actually compiled Armory from source directly on my Pi. This guide is probably more for the bitcoin 'power user', as to run Armory online, and broadcast the signed transactions, you need to have a bitcoin full node running (bitcoind). Basic requirements:
Online machine - running a full node (bitcoind)
Raspberry Pi - I used an old Pi 1 Model B with just 512Mb memory, and 2 USB slots.
2x USB thumb-drives. One for wallet backups, the other for transferring unsigned tx's to the rPi, and signed tx's back to the Desktop.
Armory 0.96.4 for the Raspberry Pi 1, Model B (512Mb RAM, 2xUSB) (compiled from github sourcecode on the Pi itself!)
Using the Pi as an offline complement to a Debian Desktop "watch-only" Armory install.
Desktop Debian Armory watch-only talks to my full node, bitcoind, which is also on the Debian desktop.
I'll post the guide in digestible sections...
I should begin by saying I installed source code from git, and got Armory to build the DB on my desktop initially, WITHOUT creating a wallet.. (This allowed me to debug what was going on a little!)
Go to Bitcoin.org, select Armory.. It leads to a Download from Git: https://github.com/goatpig/BitcoinArmory/releases Followed the procedure for Linux Debian verify code, compile, install, all straight-forward.. Began by running bitcoind, and telling Armory where to find it. This is the command I used, obviously it was all on one line and didn't include the arrows/explanations!:
python ArmoryQt.py \ --satoshi-datadir=/BlockChain/chain20180414/blocks \ # <-----(where my bitcoind blocks live) --datadir=/ArmoryDataDi \ # <-----(this is instead of ~/.armory) --dbdir=/ArmoryDataDidatabases # <-------(again, non std. place used for Armory's databases.. my choice.)
So, on the Desktop, after the initial "build databases" (NB the initial "Build Databases" took about 1.5h and my two CPUs were maxed the whole time, Temps up to 62C. Not ideal; Im not in a rush!) I then wanted to import a watch-only wallet. Before I did this, I took a full backup of the Armory data dir: /ArmoryDataDi (or ~/.armory in a default installation). I'd hate to have to make Armory do another full sync with the bitcoind node!
Next step: offline wallet (with Private Keys) is on a Raspberry Pi. I downloaded the source and managed to compile it on the pi itself! :) Though there were some gymnastics needed to setup the Pi. My Pi is running Raspbian based on Wheezy.. quite old! I did the following on the Pi:
apt-get update apt-get upgrade (<---took about an hour!) apt-get install autotools-dev apt-get install autoconf
Then I followed the instructions exactly as I had done for my Debian Desktop machine, EXCEPT: I had to increase the Pi's swap space. I upped it from 100Mb to 400Mb. The compilation took 7 hours, and my poor SD card got a thrashing. But after compilation, I put the Swap back to 100Mb and Armory runs ok with about 150Mb of memory (no swap needed). Swap increase on the Pi: use your favourite editor, and open the file /etc/dphys-swapfile add/change the following line:
Then, REBOOT the Pi:
sudo shutdown -h -P now
Once the compilation was done on the Pi, put the swap back, rebooted and created an Armory wallet. I added manual entropy and upped the encryption 'time' from 250ms to 2500ms - since the Pi is slow, but I'll be happy to wait for more iterations in the Key Derivation Function. Once the wallet was created, it obviously prompts you for backup. I want to add a private key of my own (i.e. import), so don't do the backup until this is over. I import my Private Key, and Armory checks that this corresponds to a Public Key, which I check is correct. This is the point now where the Pi storage medium (e.g an SD card) has to be properly destroyed if you ever get rid of it. I had thought that now would be a good time to decide if your new wallet will generate Segwit receiving addresses, and also addresses used to receive 'change' after a transaction.. But it seems Armory WON'T let you switch to P2SH-P2WPKH unless your Armory is connected to a node offering "WITNESS" service. Obviously, my Pi is offline and will never connect to a node, so the following will not work on the Pi:
x Use File Settings Fee and address types.
x Set the "Preferred Receive Address Type" to P2SH-P2WPKH
x Also Set the "Change Address" to P2SH-P2WPKH for left-over loose change!
NB: I thought about setting this on the Debian "watch-only" wallet, but that would surely mean doom, as the Pi would not know about those addresses and backups might not keep them.. who knows... So, end result:- no segwit for me just yet in my offline funds.
--If anyone can offer a solution to this, I'd be very grateful--
Ok, now this is a good point to back up your wallet on the Pi. It has your imported keys. I choose a Digital Backup - and put it on a USB key, which will never touch the internet and will be stored off-site. I also chose to encrypt it, because I'm good with passwords.. NB: The Armory paper backup will NOT back up your imported private keys, so keep those somewhere if you're not sweeping them. It would be prudent to have an Armory paper backup anyway, but remember it will likely NOT help you with that imported key. Now for the watch-only copy of the wallet. I want to get the "watch-only" version onto my Desktop Debian machine. On the Pi, I created (exported to a USB key) a "watching-only" copy of my wallet. I would use the RECOMMENDED approach, export the "Entire Wallet File". As you will see below, I initially exported only the ROOT data, which will NOT capture the watching-only part of the Private Key I entered manually above (i.e. the public Key!). Now, back on the Debian Desktop machine... I stopped all my crontab jobs; just give Armory uninterrupted CPU/memory/disk... I also stopped bitcoind and made a backup prior to any watch-only wallet being imported. I already made a backup of Armory on my Desktop, before any wallet import. (this was needed, as I made a mistake.. see below) So on the Debian Desktop machine, I begin by firing up bitcoind. my command for this is:
I know from bitter experience that doing a scan over the blockchain for a new wallet takes a looong time and a lot of CPU, and I'd like it to play nicely; not gobble all the memory and swap and run my 2xCPUs both at 100% for four hours... So... I aim to run with --ram-usage=X and --thread-count=X (For me in the end, X=1 but I began with X=4) I began with --ram-usage=4 (<--- = 4x128Mb) The result is below...
TypeError: cannot concatenate 'str' and 'int' objects
It didn't recognise the ram-usage and carried on, crippling my Debian desktop PC. This is where it gets dangerous; Armory can gobble so much memory and CPU that the windowing environment can cease up, and it can take over 30 minutes just to exit nicely from bitcoind and ArmoryDB. So, I ssh to the machine from another computer, and keep an eye on it with the command
I'd also be able to do a "sudo reboot now" if needed from here.
So, trying to get my --ram-usage command recognised, I tried this line (added quotes):
Loading Armory Engine: Armory Version: 0.96.4 Armory Build: None PyBtcWallet Version: 1.35 Detected Operating system: Linux OS Variant : ('debian', '9.4', '') User home-directory : /home/ Satoshi BTC directory : /BlockChain/chain20180414 Armory home dir : /ArmoryDataDi ArmoryDB directory : /ArmoryDataDidatabases Armory settings file : /ArmoryDataDiArmorySettings.txt Armory log file : /ArmoryDataDiarmorylog.txt Do wallet checking : True (ERROR) ArmoryUtils.py:3723 - Unsupported language specified. Defaulting to English (en) (ERROR) ArmoryQt.py:1833 - Failed to start Armory database: cannot concatenate 'str' and 'int' objects Traceback (most recent call last): File "ArmoryQt.py", line 1808, in startArmoryDBIfNecessary TheSDM.spawnDB(str(ARMORY_HOME_DIR), TheBDM.armoryDBDir) File "/BitcoinArmory/SDM.py", line 387, in spawnDB pargs.append('--ram-usage=' + ARMORY_RAM_USAGE) TypeError: cannot concatenate 'str' and 'int' objects
So, I edit the Armory python file SDM.py:
if ARMORY_RAM_USAGE != -1: pargs.append('--ram-usage=4') #COMMENTED THIS, SO I CAN HARDCODE =4 # ' + ARMORY_RAM_USAGE)
Running it, I now have acknowledgement of the --ram-usage=4:
(WARNING) SDM.py:400 - Spawning DB with command: /BitcoinArmory/ArmoryDB --db-type="DB_FULL" --cookie --satoshi-datadir="/BlockChain/chain20180414/blocks" --datadir="/ArmoryDataDi" --dbdir="/ArmoryDataDidatabases" --ram-usage=4
Also, even with ram-usage=4, it used too much memory, so I told it to quit. It took over 30 minutes to stop semi-nicely. The last thing it reported was:
ERROR - 00:25:21: (StringSockets.cpp:351) FcgiSocket::writeAndRead FcgiError: unexpected fcgi header version
But that didn't seem to matter or corrupt the Armory Database, so I think it's ok. So, I get brave and change SDM.py as below, and I make sure my script has a command line for --ram-usage="ABCDE" and --thread-count="FGHIJ"; the logic being that these strings "ABCDE" will pass the IF criteria below, and my hardcoded values will be used...
if ARMORY_RAM_USAGE != -1: pargs.append('--ram-usage=1') #COMMENTED THIS, SO I CAN HARDCODE =1 # ' + ARMORY_RAM_USAGE) if ARMORY_THREAD_COUNT != -1 pargs.append('--thread-count=1') #COMMENTED THIS, SO I CAN HARDCODE =1 #' + ARMORY_THREAD_COUNT)
So, as usual, I use my script and start this with: ./StartArm.sh (which uses command line:)
(this forces it to use my hard-coded values in SDM.py...) So, this is the command which it reports that it starts with:
(WARNING) SDM.py:400 - Spawning DB with command: /BitcoinArmory/ArmoryDB --db-type="DB_FULL" --cookie --satoshi-datadir="/BlockChain/chain20180414/blocks" --datadir="/ArmoryDataDi" --dbdir="/ArmoryDataDidatabases" --ram-usage=1 --thread-count=1
Again, this is where it gets dangerous; Armory can gobble so much memory and CPU that the windowing environment can cease up. So I ssh to the machine and keep an eye on it with:
So, on the Debian Desktop PC, I inserted the USB stick with the watch-only wallet I exported from the Pi. Start Armory... Import "Entire Wallet File" watch-only copy. Wait 4 hours.. YAY!!! After running Armory for about 30m, the memory usage dropped by 400m... wierd... It took ~2 hours to get 40% completion. After 3.5 hours it's almost there... The memory went up to about 1.7Gb in use and 900Mb of Swap, but the machine remained fairly responsive throughout, apart from a few (10?) periods at the start, where it appeared to freeze for 10-30s at a time. (That's where my ssh session came in handy - I could check the machine was still ok with a "free -h" command) Now, I can: Create an unsigned transaction on my Desktop, Save the tx to USB stick, Move to the Pi, Sign the tx, Move back to the Desktop, Broadcast the signed tx.
My initial Mistake: This caused me to have to roll-back my Armory database, using the backup. so you should try to avoid doing this.. On the Pi, I exported only the ROOT data, which will NOT capture the watching-only part of the Private Key It is RECOMMENDED to use the Digital Export of Entire Wallet File from the Pi when making a watch-only copy. If you just export just the "ROOT data", not the "Entire Wallet File", you'll have problems if you used an imported Private Key in the offline wallet, like I did. Using the ROOT data text import, after it finished... my balance was zero. So,. I tried a Help->Rescan Balance (Restart Armory, takes 1minute to get back up and running) No Luck. Still zero balance. So, I try Rescan Databases.. This will take longer. Nah.. no luck. So, I tried again, thinking it might be to do with the fact that I imported the text "root data" stuff, instead of following the (Recommended) export of watching-wallet file. So, I used my Armory backup, and wound back the ArmoryDataDi to the point before the install of the (zero balance) wallet. (you should not need to do this, as you will hopefully use the RECOMMENDED approach of exporting the "Entire Wallet File"!)
Hey guys! I'm fairly new to this sub and to having a home lab in general and I found this community to be so kind and helping, I wanted to give back what I've learned. I'm seeing a lot of questions asked around on improvements and on what to do with x extra hardware so I thought it would be nice to have a thread to regroup that.
I'll put here some stuff I gathered and the most common questions I've seen, feel free to contribute and i'll update the post along.
oVirt -> Viurtualization
Hurrcane Electric DNS -> Dynamic DNS
No-IP -> DynamicDNS
SpiceWorks -> Misc
ERPXE -> Backup
Homelab Dashboard Posts about dashboards have been growing lately and here are some of the best that were kind enough to provide us with their sources.
Pi-hole Prevents ads from even reaching you by blocking dns queries. Works as a relay between your isp's dns server (or whichever you choose). Can also work as a local dns.
RetroPie From their website: The RetroPie Project is a collection of works that all have the overall goal to turn the Raspberry Pi into a dedicated retro-gaming console.
raspnode Tutorials for installing cryptocurrency nodes on a Raspberry Pi. Participate in the Bitcoin, Litecoin, or Ethereum network. Full nodes, SPV wallets, cold storage, offline transaction signing.
flightradar24 is a flight tracking service that provides you with real-time info about thousands of aircraft around the world.
The Plane Finder is the easiest and most accurate way to share your ADS-B and MLAT data with us.
PiAware is the world's largest flight tracking data company and provides over 10,000 aircraft operators and service companies as well as over 12,000,000 passengers with global flight tracking solutions.
CouchPotato is an wesome PVR for usenet and torrents. Just fill in what you want to see and CouchPotato will add it to your "want to watch"-list. Every day it will search through multiple NZBs & Torrents sites, looking for the best possible match. If available, it will download it using your favorite download software.
SickBeard is a PVR for newsgroup users (with limited torrent support). It watches for new episodes of your favorite shows and when they are posted it downloads them, sorts and renames them, and optionally generates metadata for them.
SickRage Automatic Video Library Manager for TV Shows. It watches for new episodes of your favorite shows, and when they are posted it does its magic.
FlexGet is a multipurpose automation tool for content like torrents, nzbs, podcasts, comics, series, movies, etc.
sabnzbd makes Usenet as simple and streamlined as possible by automating everything we can.
nzbget is a binary downloader, which downloads files from Usenet based on information given in nzb-files.
headphones is an automated music downloader for NZB and Torrent, written in Python. It supports SABnzbd, NZBget, Transmission, µTorrent and Blackhole.
= Virtualization =
XenServer is an open source project and community managed by Citrix. The project develops open source software for securely running multiple operating systems and applications on a single device, enabling hardware consolidation and automation to reduce costs and simplify IT management of servers and applications.
Proxmox is a complete open source server virtualization management software. It is based on KVM virtualization and container-based virtualization and manages KVM virtual machines, Linux containers (LXC), storage, virtualized networks, and HA clusters.
VirtualBox is a general-purpose full virtualizer for x86 hardware, targeted at server, desktop and embedded use.
SmartOS is a hypervisor lean enough to run entirely in memory, powerful enough to run as much as you want to throw at it.
KVM is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V).
oVirt is free, open-source virtualization management platform. It was founded by Red Hat as a community project on which Red Hat Enterprise Virtualization is based.
= Monitoring =
Nagios is a powerful monitoring system that enables organizations to identify and resolve IT infrastructure problems before they affect critical business processes.
OMD avoids the tedious work of manually compiling and integrating Nagios addons while at the same time avoiding the problems of pre-packaged installations coming with your Linux distribution
Pandorafms is the most flexible monitoring software in the market. With a single tool, Pandora FMS can monitor everything: infrastructure, applications, services, and business progress.
PRTG Monitoring is a network monitoring software that is powerful and easy to use. Free for 100 sensors.
Zabbix is the ultimate enterprise-level software designed for real-time monitoring of millions of metrics collected from tens of thousands of servers, virtual machines and network devices.
Observium is a low-maintenance auto-discovering network monitoring platform supporting a wide range of device types, platforms and operating systems.
LibreNMS is a fully featured network monitoring system that provides a wealth of features and device support.
Cacti is a complete network graphing solution designed to harness the power of RRDTool's data storage and graphing functionality.
Munin surveys all your computers and remembers what it saw. It presents all the information in graphs through a web interface.
ZenOSS is an award winning, open source monitoring product that automatically discovers resources, without the use of agents, and provides visibility across all aspects of your IT environment whether physical, virtual or in the cloud.
AlienVault OSSIM is an open source security information and event management system. OSSIM combines Snort, OpenVAS, Nagios, OSSEC, and other tools into a single portal with log collection and correlation.
Graylog Centralize and aggregate all your log files for 100% visibility. Use our powerful query language to search through terabytes of log data to discover and analyze important information.
= Media Center =
Plex organizes your video, music, and photo collections and streams them to all of your screens.
Kodi, if a free and open source (GPL) software media center for playing videos, music, pictures, games, and more.
Emby brings all of your home videos, music, and photos together into one place.
OpenMediaVault is the next generation network attached storage (NAS) solution based on Debian Linux. It contains services like SSH, (S)FTP, SMB/CIFS, DAAP media server, RSync, BitTorrent client and many more.
PlexPy is a tool to easily monitor and receive notify playback events from Plex.
MediaGoblin is a free software media publishing platform that anyone can run. You can think of it as a decentralized alternative to Flickr, YouTube, SoundCloud, etc.
= Remote access =
Guacamole is a clientless remote desktop gateway. It supports standard protocols like VNC and RDP.
Chrome Remote Desktop allows users to remotely access another computer through Chrome browser or a Chromebook.
mRemoteNG is a fork of mRemote, an open source, tabbed, multi-protocol, remote connections manager. mRemoteNG adds bug fixes and new features to mRemote.
= VOIP =
Elastix is an Open Source Software to establish Unified Communications. About this concept, Elastix goal is to incorporate all the communication alternatives, available at an enterprise level, into a unique solution.
Asterisk is an open source framework for building communications applications. Asterisk turns an ordinary computer into a communications server.
FreePBX is a web-based open source GUI (graphical user interface) that controls and manages Asterisk (PBX)
= Networking =
pfSense is an open-source firewall/router computer software distribution based on FreeBSD.
Open vSwitch is a production quality, multilayer virtual switch licensed under the open source Apache 2.0 license.
SophosUTM Complete Unified Threat Management protection for your network, web, email, applications, and users.
SohposXG is a fully equipped software version of the Sophos XG firewall, available at no cost for home users.
feeloadbalancer is offering the Free LoadMaster to help small companies and developers by providing them with a robust and proven load balancing option.
NetWorx is a simple and free, yet powerful tool that helps you objectively evaluate your bandwidth consumption situation.
VyOS is a community fork of Vyatta, a Linux-based network operating system that provides software-based network routing, firewall, and VPN functionality.
freeIPA is an integrated Identity and Authentication solution for Linux/UNIX networked environments.
Metiix Blockade Network-Wide Malware, Tracking, & Ad Blocking (Can also run on Raspbian)
OpenVPN is an open-source software application that implements virtual private network (VPN) techniques for creating secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities. It uses a custom security protocol that utilizes SSL/TLS for key exchange.
Smoothwall is a Free and Open Source firewall that includes its own security-hardened GNU/Linux operating system and an easy-to-use web interface.
ClearOS is an operating system for your Server, Network, and Gateway systems. It is designed for homes, small to medium businesses, and distributed environments. ClearOS is commonly known as the Next Generation Small Business Server, while including indispensable Gateway and Networking functionality.
DriveBender is the class leading storage pooling technology for Microsoft Windows. Developed by Division-M, Drive Bender allows for file redundancy via file duplication, and unlike RAID, does not require any proprietary drive format or complicated setup. (Now free)
CloudExtender is local Windows storage, powered by the cloud... with optional, state of the art TNO (trust no one) file encryption built right in. Create a Windows drive or folder that maps directly to your favorite storage platform in minutes.
SnapRAID is a backup program for disk arrays. It stores parity information of your data and it recovers from up to six disk failures.
flexRAID is a family of storage data protection products that provide great flexibility and various innovations. The current product line includes: RAID over File System (RAID-F) Transparent RAID (tRAID).
freeNAS is an operating system that can be installed on virtually any hardware platform to share computer data storage over a computer network.
Rockstor is a free and open source NAS(Network Attached Storage) solution. It's a software solution and can be installed on any hardware or a virtual machine satisfying these minimum requirements.
nas4free The NAS4Free operating system can be installed on virtually any hardware platform to share computer data storage over a computer network.
Xpenology is the name of a Linux boot image, which allows to run operating system Sinology DSM on almost any hardware (not just Synology).
owncloud is a self-hosted file sync and share server.
openFiler provides a simple way to deploy and manage networked storage.
openATTIC openATTIC combines open source storage tools in such a way that their entire functionality can be managed through a central interface. Carefully matched components ensure both stability and security. Its open interface enables you to integrate openATTIC to provisioning, monitoring and backup systems.
= Cameras =
iSpy is the world’s most popular open source video surveillance application.
ZoneMinder is intended for use in single or multi-camera video security applications.
motioneyeOS is a Linux distribution that turns your single board computer into a video surveillance system.
Blue Iris is security camera manager. It's not free (60$ for the full version) but it was highly recommended and there doesn't seem to be any comparable free alternatives.
= Documentation =
DokuWiki is a simple to use and highly versatile Open Source wiki software that doesn't require a database.
gollum is a simple, Git-powered wiki with a sweet API and local frontend.
BookStack is a simple, self-hosted, easy-to-use platform for organising and storing information.
phpIPAM is an open-source web IP address management application (IPAM).
Paperwork aims to be an open-source, self-hosted alternative to services like Evernote ®, Microsoft OneNote ® or Google Keep ®.
afraid Free DNS Hosting, Dynamic DNS Hosting, Static DNS Hosting, subdomain and domain hosting.
No-IP's mission is to provide useful, reliable and powerful services that help home users, small and large businesses and even fortune 500 companies take control over all aspects of their DNS and domain services.
xapi-back is a simple backup tool for XenServer or XCP – xen hypervisors using xapi toolstack. xapi-back is a command line tool with simple and clear interface (command + options). Tool is written in python.
One "Public channel" for offers, "Messages" for direct communication
Bitcoin for payments
Three multisig addresses: one for the payment, two for insurance payments
Buyer and seller both send 5% of the sum to one multisig address
Both have an (5%) incentive to be honest and stick to their side of the deal
After the buyer receives the goods, all three payments are released: 5% back to the buyer, payment to the seller, 5% back to the seller
Binaries, source and complete vmware image (!) ready to download and test. edit 2014-07-11:
Sorry, I forget about README. Installation simple. If you want just .exe, download it from here http://sourceforge.net/projects/bitxbay/files/BitXBay%20Windows%20binaries/ unzip and run. If it is not running, it can be on WinXP or other old windows system, you need python 2.7 and ]pyqt or ]pyqt for 64x if you install 64x python. If you want to run sources you need python 2.7 and pyqt, then use bitmessagemain.py file. If you want to run BitXBay on linux, it can be harder. For linux you need to run bitcoin-qt manualy with settings in config in btc folder and cut string in bitmessagemain.py with running bitcoin-qt.
Transformation in trading units
Cryptography and Crypto-currency
Anonymity and Pseudonymity in cryptocurrencies
Cryptocurrency Hash codes
· Exploring Blockchain
Introduction to Blockchain.
Why Blockchain is crucial?
Key vocabulary while discussing Blockchain
The distinction between databases and blockchain
Explaining Distributed Ledger
Working on blockchain technology
Permissioned and permission-less blockchain
· Bitcoin & Blockchain o Bitcoin and its History o Why use Bitcoins? o Where and how to buy bitcoins
How to store bitcoins?
How and where to spend bitcoins?
How bitcoin transactions work
What happens in case of invalid transactions
Parameters that invalidate the transactions
The scripting language in bitcoin
Applications of bitcoin script
Nodes and network of bitcoin
Various roles you can play in the Bitcoin Ecosystem
· Ethereum · What is Ethereum?
What is Ether?
How to use Ethereum?
The Ethereum ecosystem, DApps, and DAOs
How Ethereum mining works
Contract classes, Functions, and conditionals
Inheritance & abstract contracts
Types & Optimization
Future of Ethereum
· Ethereum Private Blockchain and Smart contracts
Private and public blockchain
Various blockchain setup platforms
Using Ethereum to set up private blockchain
Steps to build a blockchain solution.
A smart contract on Ethereum
Compile, deploy and instantiate contracts
Configuring, running and working with the go-Ethereum client
Account management and mining
Understand the different stages of a contract deployment
How to interact with a contract once deployed?
· Solidity basics
Introduction to Solidity
Basics (version pragma and comments)
Structure of a contract
Data Structures (Arrays, Mapping, Structs)
Data Types (signed and unsigned int, strings, boolean, address)
Looping and Conditional Statements
· Advance Solidity
Imports and libraries
Extended String Functionality and Bytes
Custom Modifiers and Error Handling
Creating and deploying your own tokens
Event logging, handling
Parameter Mapping and Returning multiple variables
State Modifiers (Pure/View/Constant/Payable)
Transferring Ether between contracts (ERC20 and ERC223)
Introduction to the Truffle Framework
Communicating between smart contracts and HTML pages using web3.js and Metamask
Setting up event-driven Interfaces
Client-side signing and remotes nodes for Dapps · Deploying DAPP using Truffle and Web3J
Creating a project structure on Truffle
Writing the smart contract
Compiling and migrating the smart contract
Publishing the DApp
How web3.js and truffle work with ReactJS
Deploying smart contract services on the test blockchain network
Running the DApp on the Ethereum node using Metamask For Blockchain online Training contact us VLR Training 998526951
Hi, so here are a few things going on; also at the end some notes about using Joinmarket in today's environment:
Just pushed a feature to joinmarket-clientservemaster : you can now send coins to (not from) bech32 segwit addresses.
I was prompted on this by user Onecoinbob, although there's a very valid discussion about whether wallets should have gone straight to bech32 addresses (instead of p2sh wrap), the reality is that some have (in particular, Electrum) and so I think it's pretty important that people can send coins there. Whether doing direct send (no coinjoin, -N 0), coinjoin, or in joinmarket-Qt you can now use bech32 addresses like "bc1qyzd2qj8tdrvyacvtknj2xav900qkr3a2xjrmg7" as valid destinations. Only master branch for now, will make a new release soon, it's a bit overdue.
Installation: a lot of work by user arubi (thanks!) on installation, you can install with ./install.sh on Linux and probably on MacOS too.
Thanks to a couple of other users (including trotski2000), we have instructions how you can install manually in docs/INSTALL.md should there be some problem with the one-step installation. Feel free to ask on github issue or IRC or here (maybe ping me) for more help on this, but note I personally don't run a MacOS machine so I will redirect you.
A reminder: there is a Qt gui for joinmarket joinmarket-qt.py in the scripts/ directory that works Taker side, including direct sending of funds.
I recently found that people don't know this exists, indeed I first created it nearly 2 years ago!.
Backend wallet refactoring by user undeath
See the PR ; this is backend stuff so little direct relevance to users; devs may be interested, it looks like a really good effort to rationalize and improve this section of the code.
Python 3 support/migration
I have started doing work on this, but it's not a small job, Joinmarket being very byte-manipulation heavy means there's quite a lot of changes to get it working on both 2 and 3. However it's really a good idea, a lot of useful libraries are migrating to/only supported on Py3. No real date or goal here.
High fees and Joinmarket
I think most users already figured this out, but as a Taker the hit on fees from using Joinmarket is far too high in almost all cases (nothing to do with coinjoin fees; just Bitcoin network fees, which the Taker pays basically all of). It is possible in the model to share these fees, by certain sets of configuration, but the system hasn't really been set up like that. Alternatively, the Taker may lowball a fee to a crazy extent and lock up the Maker coins for a long time. I'd advise against using Joinmarket in periods of very high fees like we had last week; I'd even advise against Makers running their bots to prevent newbies suffering an unexpectedly high hit on fees. But of course everyone can make their own decision. (EDIT: Forgot to add the really important thing, which is that whatever kind of transaction you're doing, including direct_send, seriously consider using the feature that setting tx_fees to any value above 144 results in using that figure as a custom fee in satoshis per kB, with a small randomization. So setting tx_fees = 300000 in the config means using a fee of 300 sat/b. Has been mentioned before but bears repeating!) For myself, I have been actively looking at a number of alternative models (see some of my blog posts at https://joinmarket.me/blog/blog for example, my CoinswapCS repo, also "Snicker"), and of course other people are looking at things too e.g. the ZeroLink project of nopara. Joinmarket as a model may also continue to be viable if the fee regime changes, and/or when new tech comes online that changes the economics (Schnorr in particular; CT itself would radically change the economics/viability of coinjoin but that is another discussion).
Colored coin client preview #1 (based on Bitcoin Armory)
I think it's already good enough for people to play with it. (Although certainly it's not ready for anything serious.) For people who are not familiar with concept, colored coins is a technology which allows people to represent arbitrary tokens (e.g. issue private currencies, stocks, bonds, etc.) using small quantities of bitcoins. It is interesting because it would allow us to create decentralized and secure markets. (As decentralized and secure as Bitcoin itself, at least in theory.) See here. Notes about current release:
There is a GUI for issuing new coins. So all you need is like a small sum of Bitcoins, this software, and you can issue your coins and start selling them. (It is another question why people would want to buy them... Perhaps you will offer to buy them back later at higher price, thus creating bonds.)
p2p trade and auto-trade are not implemented yet, so it is only possible to trade OTC.
It is very lightly tested so please don't use it for anything serious.
It is a patched version of Armory, so it isn't lightweight at all: It requires running bitcoind or Bitcoin-Qt version 0.7.*, then it takes about 10 minutes to launch it, and in its final form it eats 1 GB of RAM. But it is totally worth it. (Yes, we are working on lightweight clients.)
(Note: if you're already using Armory, it is a good idea to hide you ~/.armory so it won't be seen by this experimental Armory mod. Or, perhaps, just don't run this experimental mod.) Before you run it, make sure that bitcoind or Bitcoin-Qt is running and fully sync'ed. Armory takes up to 10 minutes to start (this version is slower because it additionally scans for colored transactions) and requires ~ 1 GB of RAM. At start it will offer to create a wallet, do not enable encryption, otherwise issuing colored coins won't work. Send some bitcoins to this new wallet, 0.02 BTC is probably enough to issue some colored coins and to pay for tx fees. There is a drop down to choose color. Balance is displayed for a currently chosen color (i.e. if you chose TESTcc it will show how many TESTcc units this wallet owns), and when you send coins you send coins of that color. Initially 'uncolored' is selected, it means normal BTC. This drop down also has TESTcc ("test colored coins") and "All colors" (this mode is just for debugging, you cannot send coins in this mode). Here's what you can do now:
Ask somebody to send you TESTcc. (We want to make it automatic, Satoshi Dice style, but unfortunately that code isn't quite ready.)
Find and install other color definitions.
Issue your own colored coins and send them to somebody who wants them. (LOL.)
Let's start from option #3. There is 'Hallucinate' menu. (It is called 'hallucinate' because colors do not exist on blockchain level, it is a client-side convention.) Choose 'Issue colored coins'. Likely all you need to change is name, but you can tweak satoshi-per-unit and number of units if you want. When you click Issue it will create a new transaction (using your uncolored BTC) and will create a color definition. Optionally it will also upload your color definition to color definition registry. (This registry runs on my server, it might be down.) You should note ColorID, this is how other people can refer to these coins (name is ambiguous). You can now choose this new color in drop down and it will show your balance. (E.g. 1000 units.) Now you'll perhaps want to send these coins to somebody. That person would need to install your color definition first. If you send colored coins without warning they might be lost, i.e. mixed with uncolored ones. For same reason it makes no sense to send them to wallet which isn't color aware. For example, you can post on some forum:
I've issued LOLwut coins (ColorID: 36738fe78a443656535503efb585fee140a37d54), each unit represents a bond with face value of 0.1 BTC payable by me, Trololo, via buy back. I promise to buy back all bonds in a month.
Now people who are interested in this LOLwut coin issue will copy ColorID, paste it into Hallucinate > Download color definition dialog, and if this color definition is published it will be downloaded and installed. Armory restart is required to complete installation. After installation that person will be able to see these LOLwut coins. Note that if you do not trust my registration server, you can publish color definition yourself: go to ~/.armory/colordefs, find 36738fe78a443656535503efb585fee140a37d54.colordef and upload it to your web server. Then you can give people URL like http://example.com/36738fe78a443656535503efb585fee140a37d54.colordef and they can download it by URL. Or they can just obtain this file by any means and copy it to ~/.armory/colordefs directory. It is decentralized, nobody can prevent you from issuing colored coins. I think that's all. There is also Hallucinate > Manage color definitions dialog, but I hope it's easy to figure out how it works. We are working on improved version, particularly on p2p exchange feature. I've set up an IRC channel for people to talk about trying out colored coins: #colored-coins-otc on Freenode.
Is there any utility that lets you convert private key from "5" (wif format) to "L" (compressed key) for Linux which runs from command line.
I would be glad to have any solution Python, Perl, Bash or any application written for Linux. Because I need to convert the Bitcoin addresses from vanitygen into Bitcoin-Qt compatible format. I don't need such options which presume installing heavy wallets like Armory, Electrum, etc, because they presume importing addresses into their address book which won't let me be flexible enough with scripts and huge volume of private keys/public keys. Even though I appreciate if someone could help with these, it feels very ridiculous to me that bitcoin is so immature that very often I can't find necessary tools for many programming tasks in Linux automation and the whole thing with signing transactions in an automated way is so complicated! It shouldn't be like that. Linux is the most essential tool for developer but currently awesome libs like python-bitcoinlib written by Peter Todd are available only for people who know Python, which is really disappointing, because it create barriers for me since I'm not a programmer even though I know Linux/Bash/PHP
[TUTORIAL:] Creating a custom wallet. Part 1: Proof of concept.
Tested Platform Ubuntu 13.10
Tested Language Python 2.7
Download and view this tutorial onGITHUB I'm teaching myself the technical aspects of Bitcoin. I decided to start by making a custom wallet. Here is my quick and dirty proof of concept using Python, bitoinrpc, and PyQt. So far, this only queries bitcoind for getinfo. It's only a stepping stone to the greater application. I'll make more tutorials as the program develops. Please feel free to comment and ask questions. Keep in mind, Python isn't my primary language. I decided to go with Python only because I could use the practice. I wrote this using Linux. It should work on Windows / Mac, but your mileage may vary. To use this, you are going to need Python 2.7 installed on your machine (obviously) as well as the dependent libraries: PyQt, Python bitcoinrpc, and json. Copy and paste the code in a file somewhere and run
Change "rpc_username" and "rpc_password" to match that of ~/.bitcoin/bitcoin.conf Make sure ./bitcoind -server is running If everything is set up correctly you should see a gui app appear with the same information as if you were to run bitcoind getinfo from the command line.
#!/usbin/python # -*- coding: utf-8 -*- import sys from PyQt4 import QtGui from bitcoinrpc.authproxy import AuthServiceProxy import json class Configuration(): def __init__(self): self.protocol = "http" self.username = "rpc_username" self.password = "rpc_password" self.ip = "localhost" #self.port = "18332" self.port = "8332" def get_uri(self): self.uri = self.protocol+"://"+self.username+":"+self.password+"@"+self.ip+":"+self.port return self.uri class Command(): def __init__(self): self.conf = Configuration() self.access = AuthServiceProxy(self.conf.get_uri()) def get_info(self): self.info = self.access.getinfo() #self.info = self.access.listaccounts() return self.info class UI(QtGui.QWidget): def __init__(self): super(UI, self).__init__() self.init_ui() def init_ui(self): command = Command() info = command.get_info() keys = info.keys() label =  line_edit =  for (i, key) in enumerate(keys): label.append(QtGui.QLabel(str(keys[i]))) line_edit.append(QtGui.QLineEdit(str(info[keys[i]]))) grid = QtGui.QGridLayout() grid.setSpacing(10) for (i, item) in enumerate(label): grid.addWidget(label[i], i, 0) grid.addWidget(line_edit[i], i, 1) self.setLayout(grid) self.setGeometry(300, 300, 350, 300) self.setWindowTitle('getinfo') self.show() def main(): app = QtGui.QApplication(sys.argv) ex = UI() sys.exit(app.exec_()) if __name__ == '__main__': main()
Features of note:
You can replace getinfo with other commands (about line 20ish) listaccounts is commented out, but the GUI will adjust itself according to the information provided.
In the future I may just link to a github account. Time permitting. Let me know what you think. Thanks!
Question about Electrum offline wallet on a live USB
So I thought I'd try out Electrum instead of using the core bitcoin client. I read these instructions on how to create an offline Electrum wallet on a bootable ubuntu USB. In the instructions it says to leave the persistence to 'Live Mode' when creating the USB, but later on after installing python-QT and Electrum you have to reboot the USB on an offline computer. Don't you kinda need the persistence setting on to keep those things installed on the live USB after shutting down? (I'm a linux noob - please forgive my ignorance). Also I'm guessing unplugging my Windows pc's ethernet cable when running Electrum for the first time (booted from the ubuntu live USB) isn't enough security wise? Or maybe it is ok as long as this copy of Electrum won't be used online anymore? (again, I've never used Electrum before so this offline/online use is still taking time to sink in). Any advice/assurance appreciated :)
Bitcoin Core 0.10.0 released | Wladimir | Feb 16 2015
Wladimir on Feb 16 2015: Bitcoin Core version 0.10.0 is now available from: https://bitcoin.org/bin/0.10.0/ This is a new major version release, bringing both new features and bug fixes. Please report bugs using the issue tracker at github: https://github.com/bitcoin/bitcoin/issues The whole distribution is also available as torrent: https://bitcoin.org/bin/0.10.0/bitcoin-0.10.0.torrent magnet:?xt=urn:btih:170c61fe09dafecfbb97cb4dccd32173383f4e68&dn;=0.10.0&tr;=udp%3A%2F%2Ftracker.openbittorrent.com%3A80%2Fannounce&tr;=udp%3A%2F%2Ftracker.publicbt.com%3A80%2Fannounce&tr;=udp%3A%2F%2Ftracker.ccc.de%3A80%2Fannounce&tr;=udp%3A%2F%2Ftracker.coppersurfer.tk%3A6969&tr;=udp%3A%2F%2Fopen.demonii.com%3A1337&ws;=https%3A%2F%2Fbitcoin.org%2Fbin%2F Upgrading and downgrading How to Upgrade If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), then run the installer (on Windows) or just copy over /Applications/Bitcoin-Qt (on Mac) or bitcoind/bitcoin-qt (on Linux). Downgrading warning Because release 0.10.0 makes use of headers-first synchronization and parallel block download (see further), the block files and databases are not backwards-compatible with older versions of Bitcoin Core or other software:
Blocks will be stored on disk out of order (in the order they are
received, really), which makes it incompatible with some tools or other programs. Reindexing using earlier versions will also not work anymore as a result of this.
The block index database will now hold headers for which no block is
stored on disk, which earlier versions won't support. If you want to be able to downgrade smoothly, make a backup of your entire data directory. Without this your node will need start syncing (or importing from bootstrap.dat) anew afterwards. It is possible that the data from a completely synchronised 0.10 node may be usable in older versions as-is, but this is not supported and may break as soon as the older version attempts to reindex. This does not affect wallet forward or backward compatibility. Notable changes Faster synchronization Bitcoin Core now uses 'headers-first synchronization'. This means that we first ask peers for block headers (a total of 27 megabytes, as of December 2014) and validate those. In a second stage, when the headers have been discovered, we download the blocks. However, as we already know about the whole chain in advance, the blocks can be downloaded in parallel from all available peers. In practice, this means a much faster and more robust synchronization. On recent hardware with a decent network link, it can be as little as 3 hours for an initial full synchronization. You may notice a slower progress in the very first few minutes, when headers are still being fetched and verified, but it should gain speed afterwards. A few RPCs were added/updated as a result of this:
getblockchaininfo now returns the number of validated headers in addition to
the number of validated blocks.
getpeerinfo lists both the number of blocks and headers we know we have in
common with each peer. While synchronizing, the heights of the blocks that we have requested from peers (but haven't received yet) are also listed as 'inflight'.
A new RPC getchaintips lists all known branches of the block chain,
including those we only have headers for. Transaction fee changes This release automatically estimates how high a transaction fee (or how high a priority) transactions require to be confirmed quickly. The default settings will create transactions that confirm quickly; see the new 'txconfirmtarget' setting to control the tradeoff between fees and confirmation times. Fees are added by default unless the 'sendfreetransactions' setting is enabled. Prior releases used hard-coded fees (and priorities), and would sometimes create transactions that took a very long time to confirm. Statistics used to estimate fees and priorities are saved in the data directory in the fee_estimates.dat file just before program shutdown, and are read in at startup. New command line options for transaction fee changes:
-txconfirmtarget=n : create transactions that have enough fees (or priority)
so they are likely to begin confirmation within n blocks (default: 1). This setting is over-ridden by the -paytxfee option.
-sendfreetransactions : Send transactions as zero-fee transactions if possible
(default: 0) New RPC commands for fee estimation:
estimatefee nblocks : Returns approximate fee-per-1,000-bytes needed for
a transaction to begin confirmation within nblocks. Returns -1 if not enough transactions have been observed to compute a good estimate.
estimatepriority nblocks : Returns approximate priority needed for
a zero-fee transaction to begin confirmation within nblocks. Returns -1 if not enough free transactions have been observed to compute a good estimate. RPC access control changes Subnet matching for the purpose of access control is now done by matching the binary network address, instead of with string wildcard matching. For the user this means that -rpcallowip takes a subnet specification, which can be
a single IP address (e.g. 126.96.36.199 or fe80::0012:3456:789a:bcde)
a network/CIDR (e.g. 188.8.131.52/24 or fe80::0000/64)
a network/netmask (e.g. 184.108.40.206/255.255.255.0 or fe80::0012:3456:789a:bcde/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff)
An arbitrary number of -rpcallow arguments can be given. An incoming connection will be accepted if its origin address matches one of them. For example: | 0.9.x and before | 0.10.x | |--------------------------------------------|---------------------------------------| | -rpcallowip=192.168.1.1 | -rpcallowip=192.168.1.1 (unchanged) | | -rpcallowip=192.168.1.* | -rpcallowip=192.168.1.0/24 | | -rpcallowip=192.168.* | -rpcallowip=192.168.0.0/16 | | -rpcallowip=* (dangerous!) | -rpcallowip=::/0 (still dangerous!) | Using wildcards will result in the rule being rejected with the following error in debug.log:
Error: Invalid -rpcallowip subnet specification: *. Valid are a single IP (e.g. 220.127.116.11), a network/netmask (e.g. 18.104.22.168/255.255.255.0) or a network/CIDR (e.g. 22.214.171.124/24).
REST interface A new HTTP API is exposed when running with the -rest flag, which allows unauthenticated access to public node data. It is served on the same port as RPC, but does not need a password, and uses plain HTTP instead of JSON-RPC. Assuming a local RPC server running on port 8332, it is possible to request:
In every case, EXT can be bin (for raw binary data), hex (for hex-encoded binary) or json. For more details, see the doc/REST-interface.md document in the repository. RPC Server "Warm-Up" Mode The RPC server is started earlier now, before most of the expensive intialisations like loading the block index. It is available now almost immediately after starting the process. However, until all initialisations are done, it always returns an immediate error with code -28 to all calls. This new behaviour can be useful for clients to know that a server is already started and will be available soon (for instance, so that they do not have to start it themselves). Improved signing security For 0.10 the security of signing against unusual attacks has been improved by making the signatures constant time and deterministic. This change is a result of switching signing to use libsecp256k1 instead of OpenSSL. Libsecp256k1 is a cryptographic library optimized for the curve Bitcoin uses which was created by Bitcoin Core developer Pieter Wuille. There exist attacks against most ECC implementations where an attacker on shared virtual machine hardware could extract a private key if they could cause a target to sign using the same key hundreds of times. While using shared hosts and reusing keys are inadvisable for other reasons, it's a better practice to avoid the exposure. OpenSSL has code in their source repository for derandomization and reduction in timing leaks that we've eagerly wanted to use for a long time, but this functionality has still not made its way into a released version of OpenSSL. Libsecp256k1 achieves significantly stronger protection: As far as we're aware this is the only deployed implementation of constant time signing for the curve Bitcoin uses and we have reason to believe that libsecp256k1 is better tested and more thoroughly reviewed than the implementation in OpenSSL.  https://eprint.iacr.org/2014/161.pdf Watch-only wallet support The wallet can now track transactions to and from wallets for which you know all addresses (or scripts), even without the private keys. This can be used to track payments without needing the private keys online on a possibly vulnerable system. In addition, it can help for (manual) construction of multisig transactions where you are only one of the signers. One new RPC, importaddress, is added which functions similarly to importprivkey, but instead takes an address or script (in hexadecimal) as argument. After using it, outputs credited to this address or script are considered to be received, and transactions consuming these outputs will be considered to be sent. The following RPCs have optional support for watch-only: getbalance, listreceivedbyaddress, listreceivedbyaccount, listtransactions, listaccounts, listsinceblock, gettransaction. See the RPC documentation for those methods for more information. Compared to using getrawtransaction, this mechanism does not require -txindex, scales better, integrates better with the wallet, and is compatible with future block chain pruning functionality. It does mean that all relevant addresses need to added to the wallet before the payment, though. Consensus library Starting from 0.10.0, the Bitcoin Core distribution includes a consensus library. The purpose of this library is to make the verification functionality that is critical to Bitcoin's consensus available to other applications, e.g. to language bindings such as [python-bitcoinlib](https://pypi.python.org/pypi/python-bitcoinlib) or alternative node implementations. This library is called libbitcoinconsensus.so (or, .dll for Windows). Its interface is defined in the C header [bitcoinconsensus.h](https://github.com/bitcoin/bitcoin/blob/0.10/src/script/bitcoinconsensus.h). In its initial version the API includes two functions:
bitcoinconsensus_verify_script verifies a script. It returns whether the indicated input of the provided serialized transaction
correctly spends the passed scriptPubKey under additional constraints indicated by flags
bitcoinconsensus_version returns the API version, currently at an experimental 0
The functionality is planned to be extended to e.g. UTXO management in upcoming releases, but the interface for existing methods should remain stable. Standard script rules relaxed for P2SH addresses The IsStandard() rules have been almost completely removed for P2SH redemption scripts, allowing applications to make use of any valid script type, such as "n-of-m OR y", hash-locked oracle addresses, etc. While the Bitcoin protocol has always supported these types of script, actually using them on mainnet has been previously inconvenient as standard Bitcoin Core nodes wouldn't relay them to miners, nor would most miners include them in blocks they mined. bitcoin-tx It has been observed that many of the RPC functions offered by bitcoind are "pure functions", and operate independently of the bitcoind wallet. This included many of the RPC "raw transaction" API functions, such as createrawtransaction. bitcoin-tx is a newly introduced command line utility designed to enable easy manipulation of bitcoin transactions. A summary of its operation may be obtained via "bitcoin-tx --help" Transactions may be created or signed in a manner similar to the RPC raw tx API. Transactions may be updated, deleting inputs or outputs, or appending new inputs and outputs. Custom scripts may be easily composed using a simple text notation, borrowed from the bitcoin test suite. This tool may be used for experimenting with new transaction types, signing multi-party transactions, and many other uses. Long term, the goal is to deprecate and remove "pure function" RPC API calls, as those do not require a server round-trip to execute. Other utilities "bitcoin-key" and "bitcoin-script" have been proposed, making key and script operations easily accessible via command line. Mining and relay policy enhancements Bitcoin Core's block templates are now for version 3 blocks only, and any mining software relying on its getblocktemplate must be updated in parallel to use libblkmaker either version 0.4.2 or any version from 0.5.1 onward. If you are solo mining, this will affect you the moment you upgrade Bitcoin Core, which must be done prior to BIP66 achieving its 951/1001 status. If you are mining with the stratum mining protocol: this does not affect you. If you are mining with the getblocktemplate protocol to a pool: this will affect you at the pool operator's discretion, which must be no later than BIP66 achieving its 951/1001 status. The prioritisetransaction RPC method has been added to enable miners to manipulate the priority of transactions on an individual basis. Bitcoin Core now supports BIP 22 long polling, so mining software can be notified immediately of new templates rather than having to poll periodically. Support for BIP 23 block proposals is now available in Bitcoin Core's getblocktemplate method. This enables miners to check the basic validity of their next block before expending work on it, reducing risks of accidental hardforks or mining invalid blocks. Two new options to control mining policy:
-datacarrier=0/1 : Relay and mine "data carrier" (OP_RETURN) transactions
if this is 1.
-datacarriersize=n : Maximum size, in bytes, we consider acceptable for
"data carrier" outputs. The relay policy has changed to more properly implement the desired behavior of not relaying free (or very low fee) transactions unless they have a priority above the AllowFreeThreshold(), in which case they are relayed subject to the rate limiter. BIP 66: strict DER encoding for signatures Bitcoin Core 0.10 implements BIP 66, which introduces block version 3, and a new consensus rule, which prohibits non-DER signatures. Such transactions have been non-standard since Bitcoin v0.8.0 (released in February 2013), but were technically still permitted inside blocks. This change breaks the dependency on OpenSSL's signature parsing, and is required if implementations would want to remove all of OpenSSL from the consensus code. The same miner-voting mechanism as in BIP 34 is used: when 751 out of a sequence of 1001 blocks have version number 3 or higher, the new consensus rule becomes active for those blocks. When 951 out of a sequence of 1001 blocks have version number 3 or higher, it becomes mandatory for all blocks. Backward compatibility with current mining software is NOT provided, thus miners should read the first paragraph of "Mining and relay policy enhancements" above. 0.10.0 Change log Detailed release notes follow. This overview includes changes that affect external behavior, not code moves, refactors or string updates. RPC:
f923c07 Support IPv6 lookup in bitcoin-cli even when IPv6 only bound on localhost
b641c9c Fix addnode "onetry": Connect with OpenNetworkConnection
Bitcoin software has both a graphical interface called bitcoin-qt and a console interface, bitcoind. If the first is convenient for human use, then without a text it is quite difficult to make an online store or any other service that accepts bitcoins as a payment. sudo aptitude install python-software-properties</code> sudo add-apt The Bitcoin Core daemon (bitcoind) is not included in the .dmg file you may have downloaded to install Bitcoin-QT. Bitcoind, along with its support binaries, is instead included in the OS X .tar.gz file listed on the official Bitcoin Core download page. To download this file using Terminal, execute the following command: This one’s for you. I want you to learn Linux, and I want Bitcoin to motivate you to switch. This will be as much a “Linux for Dummies” guide as it is a guide to setting up a Bitcoin node. and then back to bitcoin-qt, sudo apt-get update; sudo apt-get install git; mkdir -p bitcoin-source && cd bitcoin-source git clone https: Bitcoin Core is a community-driven free software project, released under the MIT license. Verify release signatures Download torrent Source code Show version history Bitcoin Core Release Signing Keys v0.8.6 - 0.9.2.1 v0.9.3 - 0.10.2 v0.11.0+ We are ready to install Bitcoin core at this point. To install Bitcoin Core, run the following command. “sudo apt-get install bitcoin-qt” Press ‘y’ and Press <Enter>, the installation should start. It will take a few seconds to install. Once it’s installed, click on “Show Applications” icon and you should see Bitcoin Core icon on
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