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Đang hiển thị bài đăng từ Tháng 6, 2015

How To Enable PHP 5.5 Opcache

Hình ảnh
Install Requirements yum install gcc httpd-devel php-pear pcre-devel Install Zend Opcache yum install php-pecl-zendopcache This will install Zend Opcache. Restart Server You will need to restart your server after installation for this to take effect: sudo service httpd restart Stopping httpd : [ OK ] Starting httpd : [ OK ] Test Installation [root@ip-172-31-29-134 ec2-user]# php -v PHP 5.6.9 (cli) (built: May 28 2015 00:59:21) Copyright (c) 1997-2015 The PHP Group Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies     with Zend OPcache v7.0.4-dev, Copyright (c) 1999-2015, by Zend Technologies On nginx (php-fpm) [root@ip-172-31-29-134 ec2-user]# php-fpm -v PHP 5.6.9 (fpm-fcgi) (built: May 28 2015 01:00:40) Copyright (c) 1997-2015 The PHP Group Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies     with Zend OPcache v7.0.4-dev, Copyright (c) 1999-201

Install osTicket ( Open source ticketing tool )

The osTicket is one of the famous open source ticketing tool , widely use in many organisations and companies. We will explain, how to install osTicket ( Open source ticketing tool) on Ubuntu 14.04 LTS . We will do self hosted osTicket installation. In case, you are looking for professional support for osTicket , that is also available. Why we need ticketing tool This is something important to know , why we need ticketing tool. In many IT companies , ticketing system play very vital role. We are trying to list out some of them – 1. We can track the progress of work through SLA (Service-Level Agreement) 2. We can analyse the quality of work. 3. We can record the performance of employees. 4. We can mitigate the frequent occurring issues by analysis / RCA (Root Cause Analysis) . Features of osTicket Custom Fields : Customize the data collected from users when submitting a ticket to help get straight to the issue. Rich Text HTML : Rich text or HTML email, is support

Understanding Load Average in Linux and when to be worried about it?

The one of the most important task of any Linux Admin includes performance monitoring which includes a parameter " Load Average " or " CPU Load ". Load Average is the value which represents the load on your system for a specific period of time. Also it can be considered the ratio of the number of active tasks to the number of available CPUs. How to check? You can use either top or uptime command to view the load average. The output would look like as shown below $ uptime  00:07:00 up 4 days,  6:14,  1 user,   load average: 0.11, 0.14, 0.09 $ top top - 00:07:12 up 4 days,  6:15,  1 user,   load average: 0.09, 0.13, 0.09 What are the three values? As you can see three values representing the load average column. These show the load on your system over a significant period of time (one or current, five and fifteen minutes averages). How do you know your system has a high load? The most important question as in most cases I have seen how do

HAProxy ACL for Load Balancing on URL Request

Until today I was using the basic HAProxy settings, Today i found a task about selection of backend server basis of url request. While working on this task, I learned about HAProxy ACLs. Task: I have wordpress installed as http://domainname.com/blog . This domain is running from 2 backend server and balanced by HAProxy, The task is to redirect all /blog requrest to only single server. Network Scenario for this setup HAProxy Server: 192.168.1.90 WEB1 : 192.168.1.103 WEB2 : 192.168.1.105 Domain: tecadmin.net The below example includes ACL for url_beg. url_beg matches the string used in url submitted. Using the url all requests starting with /blog ( tecadmin.net/blog ) will redirect to WEB2 ( 192.168.1.105 ) Server. All other requests will redirect to one of two server ( WEB1, WEB2 ), depending on load balancing algorithm used. Here is a quick example of uses url_beg ACL:   global log 127.0.0.1 local0 notice maxconn 50000 daemon defaults log globa

IP Failover Setup using KeepAlived on CentOS/RHEL 6

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Keepalived is used for IP failover between two servers. It facilities for load balancing and high-availability to Linux based infrastructures. It works on VRRP ( Virtual Router Redundancy Protocol ) protocol. We have running two load balance servers using HAProxy and now we need to implement VRRP between both servers. This tutorial will help you to configure KeepAlived, Use this tutorial to configure HAProxy on both servers. Network Scenario: 1. LB1 Server: 192.168.10.111 ( eth1 ) 2. LB2 Server: 192.168.10.112 ( eth1 ) 3. Virtual IP: 192.168.10.121 Now we are implementing ip failover setup between LB1 and LB2 servers. Graphical representation of Fail over Setup: Step 1: Install Required Packages Use following command to install required packages to configure Keepalived on server. # yum install gcc kernel-headers kernel-devel Step 2: Install Keepalived Keepalived is available in centos base repository. Install it using yum command line tool. # yum install

Centralize authorized_keys file on Linux / Unix system

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Authorized_keys are important files which has the information of public keys for public key authentication. By default location is ~/.ssh/authorized_keys. Here, ~ is users default home directory in system. While working on SSH, we got requirement to centralize the authorized_keys of all users existing in system. In most of the system for SSH we use the OpenSSH package. Hence, the default location for SSH config file is /etc/ssh/sshd_config . Centralizing the authorized_keys for all users is quite easy. We believe you already have some experience on public and private ssh key pairs, because for access user need SSH private key. Step 1: List the users name exist in system Gather the information of existing users from /etc/passwd file . Make a list of users to whom you want to give access in system with SSH key authentication method. For example , I found some valid users from system like – joe mike Joseph Step 2 : Create a new directory Create a new directory in

Install rrdtool 1.4 on CentOS 6

I got the error after I install Check_mk 1.2.4p2. When I try to check one of the many network interfaces in Check_MK, the graphs of some parameters are not shown. Instead I see a red box with white fonts saying ERROR: Unknown function 'PERCENTNAN' in VDEF 'outpercmb' For fix this issue I installed latest version rrdtool Download latest version rrdtool # wget http://pkgs.repoforge.org/rrdtool/perl-rrdtool-1.4.7-1.el6.rfx.x86_64.rpm # wget http://pkgs.repoforge.org/rrdtool/rrdtool-devel-1.4.7-1.el6.rfx.x86_64.rpm # wget http://pkgs.repoforge.org/rrdtool/rrdtool-1.4.7-1.el6.rfx.x86_64.rpm Install all dependencies for rrdtool # yum install libdbi ruby xorg-x11-fonts-Type1 perl-Time-HiRes gettext libpango libpangocairo pango -y We need remove old version # yum erase rrdtool -y Install rrdtool from rpm packages # rpm -Uvh perl-rrdtool-1.4.7-1.el6.rfx.x86_64.rpm rrdtool-1.4.7-1.el6.rfx.x86_64.rpm rrdtool-devel-1.4.7-1.el6.rfx.x86_64.rpm