Linux

DevStack is a project whose purpose is to quickly deploy a development and testing environment for OpenStack. DevStack supports Ubuntu 16.04/17.04, Fedora 24/25, CentOS/RHEL 7, as well as Debian and OpenSUSE. In this article, we will install the Ocata version of OpenStack. DevStack installs the following modules by default: Keystone: Identity service. Nova: Virtualization management module. Cinder: Storage. Neutron: Network module. Horizon: Web interface. Warning: DevStack is not designed to be restarted. It cannot be used as a production environment. ...

Jenkins is an open source continuous integration tool developed in Java. Adding Repositories to Install Java 8 Adding repositories: echo "deb http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main" | tee /etc/apt/sources.list.d/webupd8team-java.list echo "deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main" | tee -a /etc/apt/sources.list.d/webupd8team-java.list Adding the package verification certificate: apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886 Updating repositories: apt-get update Installing Java 8 Install the Java 8 package and accept its terms of use: apt-get install oracle-java8-installer Installing Jenkins We will use wget to download the Jenkins .war file: ...

I’ve been interested in the Ethereum blockchain for a while now, particularly the “Smart Contract” feature. A smart contract is a script deployed on the blockchain that miners execute in exchange for a variable amount of money depending on the script’s content. But to test these smart contracts, you need to set up a private Ethereum network. This tutorial requires a minimal understanding of the Ethereum blockchain and “Proof of Work” systems. ...

The Remote is Git’s network backup system. GitHub is nothing more than a Remote manager with a Web interface. The connection uses the SSH protocol. Installing Git on the Server sudo apt-get install git Creating the Git User The “git” user will allow us to interact with the remote repository. sudo adduser --system --shell /bin/bash --group --disabled-password --home /var/git/ git Then change the owner of the “/var/git” directory, which was created during git installation and is the home directory of the git user. ...

Today, email providers all have anti-spam filters. Some simply move the email to a “spam” folder, but others delete the email entirely. To counter this problem, sending servers must prove their legitimacy. Prerequisites: A Linux VPS with internet access A domain name Here, we will use a Debian 7 VPS and an OVH domain. Installing Postfix and mailutils Postfix will be our mail sending server. Installing Postfix sudo apt-get install postfix During installation, you are asked which type of configuration you want. Choose “Internet Site”, which is a basic configuration without redirecting to other servers. Then you are asked for the server’s domain name. ...