My OpenStack development environment is build using RDO’s packstack utility and consists of three nodes: one controller, network, and compute node, and two compute nodes. RDO website offers two scenario for upgrading OpenStack Mitaka to OpenStack Newton. The first scenario involves taking down all of the OpenStack services at once and will not bring them back up until the upgrade process is completed. The second scenario upgrades each OpenStack service one by one to avoid downtime by performing rolling upgrades of the compute hosts, taking advantage of the fact that nova-compute from Mitaka can communicate with a Newton control plane.
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We will use ProxySQL as a gateway to access our Percona XtraDB Cluster. ProxySQL is a high-performance SQL proxy. ProxySQL runs as a daemon watched by a monitoring process. The process monitors the daemon and restarts it in case of a crash to minimize downtime. The daemon accepts incoming traffic from MySQL clients and forwards it to backend MySQL servers.
Installing ProxySQL Node configuration Node Host IP Node 1 db1 192.168.50.31 Node 2 db2 192.168.50.32 Node 3 db3 192.168.50.33 Node 4 proxysql 192.168.50.34 Prerequisites Install CentOS 7
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· 13 min read#sysadmin#database#mysql#percona#proxysql
Percona XtraDB Cluster is a database clustering solution for MySQL. It ensures high availability, prevents downtime and data loss, and provides linear scalability for a growing environment. Here we will try to install Percona XtraDB Cluster on a three nodes cluster configuration with the help from Ansible configuration management.
Installing Percona XtraDB Cluster on Red Hat Enterprise Linux and CentOS 7 Node configuration Node Host IP Node 1 db1 192.168.50.31 Node 2 db2 192.168.50.32 Node 3 db3 192.168.50.33 Prerequisites Install CentOS 7 Update CentOS 7 Open firewall for TCP ports 3306, 4444, 4567, 4568: ansible -i hosts -bkKv db-cluster -m firewalld -a 'port=3306/tcp permanent=true state=enabled immediate=yes' ansible -i hosts -bkKv db-cluster -m firewalld -a 'port=4444/tcp permanent=true state=enabled immediate=yes' ansible -i hosts -bkKv db-cluster -m firewalld -a 'port=4567/tcp permanent=true state=enabled immediate=yes' ansible -i hosts -bkKv db-cluster -m firewalld -a 'port=4568/tcp permanent=true state=enabled immediate=yes' Disable or set SELinux to Permissive, set option below in /etc/selinux/config and /etc/sysconfig/selinux:
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Salah satu fitur OpenStack adalah elastisitasnya yang memungkinkan kita untuk membuat dan menjalankan instance dengan cepat dan mudah menggunakan image dari sistem operasi yang sudah kita buat sebelumnya. Tutorial kali ini akan memberikan salah satu cara membuat sendiri image sistem operasi CentOS 7 untuk digunakan di OpenStack Liberty.
Persiapan Host Environment Host yang kita gunakan untuk membuat image adalah host dengan sistem operasi CentOS 7. Pastikan sudah terinstall virtualisasi KVM/libvirtd dan tools yang diperlukan
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Virtualenv Virtualenv adalah aplikasi untuk membuat membuat environment virtual Python terisolasi. Aplikasi ini membuat sebuah environment virtual yang mempunyai direktori instalasi sendiri, yang tidak berbagi library dengan environment Virtualenv lainnya dan dapat dikonfigurasi untuk tidak mengakses library yang diinstal secara global.
Instal pip di sistem operasi masing-masing, contohnya CentOS
sudo yum update -y sudo yum install -y python-pip Instal virtualenv menggunakan pip
sudo pip install virtualenv Buat environment virtual Python menggunakan virtualenv
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Let’s Encrypt adalah Certificate Authority (CA) yang gratis dan terotomatisasi yang berjalan untuk kepentingan umum. Let’s Encrypt adalah sebuah layanan yang disediakan oleh Internet Security Research Group (ISRG). Prinsip-prinsip dasar dari Let’s Encrypt adalah gratis, otomatis, aman, transparan, terbuka, dan koperatif.
Instalasi Let’s Encrypt Instalasi Let’s Encrypt
sudo yum -y install git bc sudo git clone https://github.com/letsencrypt/letsencrypt /opt/letsencrypt Buat sertifikat baru untuk domain example.com, sebelumnya hentikan dulu aplikasi Nginx
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Setelah kita melakukan instalasi email server, cek skor email server di website Mail Tester. Salah satu contoh hasil pengecekan website tersebut sebagai berikut.
Content: [Text] [HTML] [Source] SpamAssassin: [Score] The famous spam filter SpamAssassin. A score below -5 is considered spam. Authentication: We check if the server you are sending from is authenticated [SPF] Sender Policy Framework (SPF) is an email validation system designed to prevent email spam by detecting email spoofing, a common vulnerability, by verifying sender IP addresses. [Sender ID] Sender ID is like SPF, but it checks the FROM address, not the bounce address. [DKIM] DomainKeys Identified Mail (DKIM) is a method for associating a domain name to an email message, thereby allowing a person, role, or organization to claim some responsibility for the message. [DMARC record] A DMARC policy allows a sender to indicate that their emails are protected by SPF and/or DKIM, and give instruction if neither of those authentication methods passes. Please be sure you have a DKIM and SPF set before using DMARC. [PTR record] Reverse DNS lookup or reverse DNS resolution (rDNS) is the determination of a domain name that is associated with a given IP address. Some companies such as AOL will reject any message sent from a server without rDNS, so you must ensure that you have one. You cannot associate more than one domain name with a single IP address. [A record] We check if there is a mail server (A Record) behind your hostname. Errors: Checks whether your message is well formatted or not. [Image alternate tag] alt attributes provide a textual alternative to your images. It is a useful fallback for people suffering from sight problems and for cases where your images cannot be displayed. [HTML elements] Checks whether your message contains dangerous html elements such as javascript, iframes, embed content or applet. [URL shortener] Checks whether your message uses URL shortener systems. [List-Unsubscribe header] The List-Unsubscribe header is required if you send mass emails, it enables the user to easily unsubscribe from your mailing list. [Blacklist] Matches your server IP address against 22 of the most common ipv4 blacklists. Untuk meningkatkan skor, kita bisa memperbaiki konfigurasi email server dengan SPF dan DKIM
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· 4 min read#sysadmin#email-server#postfix#spf#dkim
Sejak FreeBSD 10.0-RELEASE, hypervisor bhyve (lisensi BSD) sudah menjadi bagian dari base system. Hypervisor adalah aplikasi yang bisa membuat dan menjalankan virtual machine atau yang biasa disebut guest di dalam sebuah sistem operasi. Guest yang didukung oleh bhyve cukup banyak, termasuk FreeBSD, OpenBSD, dan banyak distribusi Linux. Saat ini bhyve hanya mendukung konsol serial dan tidak bisa menampilkan konsol grafik. Bhyve membutuhkan prosesor baru yang mendukung Intel Extended Page Tables (EPT) atau AMD Rapid Virtualization Indexing (RVI), yang dikenal juga sebagai Nested Page Tables (NPT). Untuk Linux atau FreeBSD guest dengan vCPU (virtualCPU) membutuhkan dukungan VMX unrestricted mode (UG). Cara termudah untuk mengecek dukungan prosesor untuk bhyve adalah dengan menjalankan #dmesg# atau melihat isi /var/run/dmesg.boot untuk fitur POPCNT di baris Features dan EPT dan UG di baris VT-x. Panduan yang cukup lengkap untuk menggunakan bhyve dapat diakses di halaman ini
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By default, FreeBSD doesn’t install a python package in its standard distribution. So, we need to install python, either manually or using ansible module.
ansible freebsd-host -m raw -a 'env ASSUME_ALWAYS_YES=YES pkg install python' -u root Of course before we can use ansible we have to install public key authentication and enable SSH to root user in FreeBSD host from controller machine. FreeBSD install python in different path than Linux machine, so we must set variable for the python interpreter, either in host file or variable files.
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Percona Server 5.6 is the latest release of drop-in replacement for MySQL®. The new version offers all the improvements found in MySQL 5.6 Community Edition plus scalability, availability, backup, and security features found only in MySQL 5.6 Enterprise Edition, which requires a support contract from Oracle to access. Percona Server 5.6 is free, open source software which includes superior diagnostics and improved integration with other Percona software. In this documentation, I will show how to install Percona Server 5.6 on CentOS 6.
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