[ How2CentOS ]

Installing PHP 5.4 on CentOS 6.2

George Rushby — Sun, 26 Aug 2012 13:38:49 +0000

The assumption for installing PHP 5.4 on CentOS 6.2 tutorial is that you are running as root and have a basic understanding of the software required but if you follow this tutorial you should be able to complete the task successfully.

Install Yum Priorities

For a brief overview on and how to configure Yum Priorities you can follow the instructions outlined in our Install YUM Priorities on CentOS tutorial.

# yum install yum-priorities

Installing PHP 5.4 on CentOS 6.2 x86_64

Install the EPEL x86_64 YUM Repository

# rpm -Uvh http://download.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-7.noarch.rpm

Install the IUS x86_64 YUM Repository

# rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/6/x86_64/ius-release-1.0-10.ius.el6.noarch.rpm

# yum install php54 php54-common php54-devel

# php -v
PHP 5.4.5 (cli) (built: Jul 23 2012 10:10:54)
Copyright (c) 1997-2012 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2012 Zend Technologies

Installing PHP 5.4 on CentOS 6.2 i386

Install the EPEL i386 YUM Repository

# rpm -Uvh http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-7.noarch.rpm

Install the IUS i386 YUM Repository

# rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/6/i386/ius-release-1.0-10.ius.el6.noarch.rpm

# yum install php54 php54-common php54-devel

# php -v
PHP 5.4.5 (cli) (built: Jul 23 2012 10:10:54)
Copyright (c) 1997-2012 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2012 Zend Technologies

Installing PHP 5.4 on CentOS 6.2

Install yum priorities on CentOS

George Rushby — Wed, 01 Aug 2012 10:39:14 +0000

[ How2CentOS ]

The Yum Priorities plugin can be used to enforce ordered protection of repositories, by associating priorities to repositories.

The priorities plugin is a useful tool if properly configured, and used with an understanding of the functionality and a recognition of the limitations and potential issues. It can be used in conjunction with the ‘exclude’ and/or ‘includepkg’ options, as well as the ‘enabled=0′ option to disable a repo by default. This can let you choose which packages a less important repo will supersede those of a more important one.

Install Yum Priorities

# yum install yum-priorities

Configure Yum Priorities

# vi /etc/yum/pluginconf.d/priorities.conf

Ensure the following lines exist

1 2	[main] enabled=1

Save and close the file

Open the CentOS base repository configuration file

# vi /etc/yum.repos.d/CentOS-Base.repo

Add the following text to the end of the base, updates and extras entries

1	priority=1

Add the following line to the end of the centosplus, contrib entries

1	priority=2

# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client.  You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the
# remarked out baseurl= line instead.
#
#
 
[base]
name=CentOS-$releasever - Base
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
#baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
priority=1
 
#released updates
[updates]
name=CentOS-$releasever - Updates
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
#baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
priority=1
 
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
#baseurl=http://mirror.centos.org/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
priority=1
 
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus
#baseurl=http://mirror.centos.org/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
priority=2
 
#contrib - packages by Centos Users
[contrib]
name=CentOS-$releasever - Contrib
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contrib
#baseurl=http://mirror.centos.org/centos/$releasever/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
priority=2

Install yum priorities on CentOS

Installing PHP 5.4 on CentOS 5.8

George Rushby — Sat, 28 Jul 2012 09:10:36 +0000

[ How2CentOS ]

This tutorial is intended for system administrators wanting to install PHP 5.4 on CentOS 5.8

The reader should know how to configure a web server or application server and have basic knowledge of the HTTP protocol. Once finished the reader should have PHP 5.4 running with the default configuration.

Install Yum Priorities

For a brief overview on and how to configure Yum Priorities you can follow the instructions outlined in our Install YUM Priorities on CentOS tutorial.

# yum install yum-priorities

Installing PHP 5.4 on CentOS 5.8 x86_64

Install the EPEL x86_64 YUM Repository

# rpm -Uvh http://download.fedoraproject.org/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm

Install the IUS x86_64 YUM Repository

# rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/x86_64/ius-release-1.0-10.ius.el5.noarch.rpm

# yum install php54 php54-common php54-devel

# php -v
PHP 5.4.5 (cli) (built: Jul 23 2012 10:10:54)
Copyright (c) 1997-2012 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2012 Zend Technologies

Installing PHP 5.4 on CentOS 5.8 i386

Install the EPEL i386 YUM Repository

# rpm -Uvh http://download.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm

Install the IUS i386 YUM Repository

# rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/i386/ius-release-1.0-10.ius.el5.noarch.rpm

# yum install php54 php54-common php54-devel

# php -v
PHP 5.4.5 (cli) (built: Jul 23 2012 10:10:54)
Copyright (c) 1997-2012 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2012 Zend Technologies

Installing PHP 5.4 on CentOS 5.8

CentOS 6.3 Released

George Rushby — Tue, 10 Jul 2012 10:59:07 +0000

[ How2CentOS ]

CentOS 6.3 has been released.

CentOS-6.3 is based on the upstream release EL 6.3 and includes packages from all variants. All upstream repositories have been combined into one, to make it easier for end users to work with.

CentOS 6.3 Downloads

You can download CentOS 6.3 via the web/ftp server or via BitTorrent (recommended) client.

CentOS 6.3 DVD ISO downloads

Choose a CentOS mirror close to you :

CentOS 6.3 Mirrors

CentOS 6.3 DVD ISO Torrents

Torrent files for the DVD’s are available at the following location:

Upgrading from CentOS-6.0 / 6.1 or 6.2

Unless you have edited your yum configs, a ‘yum update’ should move your
machine seamlessly from any previous CentOS-6.x release to CentOS-6.3

CentOS 6.3 Released

CentOS 6 NTP Server

George Rushby — Thu, 24 May 2012 13:01:07 +0000

[ How2CentOS ]

It is important for systems administrators to make sure that mission-critical servers are always using the correct system time.

The ntpd (Network Time Protocol daemon) program is an operating system daemon which sets and maintains the system time of day in synchronism with Internet standard time servers. Make sure that the time zone configuration of your computer is correct. ntpd itself does not do anything about the time zones, it just uses UTC internally.

Install Network Time Protocol (NTP) daemon

# yum install ntp

Add NTP daemon to startup

# chkconfig ntpd on

Edit the NTPD config file

Here you can either use the default NTP public servers or add servers closer to your region.

Visit http://www.pool.ntp.org/en/ and either considder joining or getting your regional NTP pool servers

# vi /etc/ntp.conf

# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
server 0.centos.pool.ntp.org
server 1.centos.pool.ntp.org
server 2.centos.pool.ntp.org

Start the NTP daemon

# service ntpd start

Standard NTP query program (ntpq)

Print a list of the peers known to the server as well as a summary of their state.

# ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
*javanese.kjsl.c 69.36.224.15 2 u 108 128 377 1.401 3.392 4.779
+66-191-139-149. 132.163.4.101 2 u 70 128 377 46.044 11.205 5.378
+ntp.sunflower.c 132.236.56.250 3 u 85 128 377 50.962 -2.129 14.112

Managing NTPd with Puppet

If you’re running Puppet we have included the manifest for installing Varnish on CentOS 6. If you’re not running Puppet then you can install it by following the instructions outlined in our CentOS 6 Puppet Install.

This is only the manifest and doesn’t include any of the files (i.e. ntp.conf).

class ntpd::install {
 
	$packagelist = ["ntp"]
 
	package { $packagelist:
		ensure => installed
	}
}
 
class ntpd::service {
 
	service { "ntpd":
		ensure => true,
		enable => true,
		hasrestart => true,
		hasstatus => true,
		require => Class ["ntpd::install"]
	}
}
 
class ntpd::conf {
 
	File {
		require => Class ["ntpd::install"],
		owner => "root",
		group => "root",
		mode => 644,
		notify => Class ["ntpd::service"]
	}
 
	file { "/etc/ntp.conf":
		source  => "puppet:///modules/ntpd/ntp.conf"
	}
}
 
class ntpd {
	include ntpd::install, ntpd::service, ntpd::conf
}

CentOS 6 NTP Server

Install Varnish CentOS 6

George Rushby — Sat, 19 May 2012 11:11:33 +0000

[ How2CentOS ]

This tutorial is intended for system administrators wanting to install Varnish on CentOS 6. The reader should know how to configure a web server or application server and have basic knowledge of the HTTP protocol. Once finished the reader should have a basic Varnish cache up and running with the default configuration.

Varnish is a web application accelerator. You install it in front of your web application and it will speed it up significantly.

Varnish web application accelerator homepage: https://www.varnish-cache.org

Install the Varnish YUM Repository

# rpm -Uvh http://repo.varnish-cache.org/redhat/varnish-3.0/el5/noarch/varnish-release-3.0-1.noarch.rpm

Install Varnish web accelerator

# yum install varnish

Enable Varnish web accelerator at startup

# chkconfig varnish on

Basic default.vcl

# vi /etc/varnish/default.vcl

# This is a basic VCL configuration file for varnish.  See the vcl(7)
# man page for details on VCL syntax and semantics.
#
# Default backend definition.  Set this to point to your content
# server.
#
backend default {
  .host = "127.0.0.1";
  .port = "80";
}

Start Varnish web accelerator

# service varnish start

You will now have a basic Varnish web accelerator running on port 8080

Top 5 Varnish commands

varnishstat

Provides all the info you need to spot cache misses and errors.

varnishhist

Provides a histogram view of cache hits/misses

varnishlog

Provides detailed information on requests.

varnishtop

The varnishtop utility reads varnishd shared memory logs and presents a continuously updated list of the most commonly occurring log entries.

varnishadm

Command-line varnish administration used to reload vcl and purge urls.

Managing Varnish with Puppet

This is only the manifest and doesn’t include any of the files (i.e. default.vcl).

class varnish::repo {
 
	Package {
		provider => rpm,
		ensure => installed
	}
 
	package { "varnish-release": source => "http://repo.varnish-cache.org/redhat/varnish-3.0/el5/noarch/varnish-release-3.0-1.noarch.rpm"
	}
}
 
class varnish::install {
 
	$packagelist = ["varnish"]
 
	package { $packagelist:
		require => Class ["varnish::repo"],
		ensure => installed
	}
}
 
class varnish::service {
 
	service { "varnish":
		ensure => true,
		enable => true,
		hasrestart => true,
		hasstatus => true,
		require => Class ["varnish::install"]
	}
}
 
class varnish::conf {
 
	File {
		require => Class ["varnish::install"],
		owner => "root",
		group => "root",
		mode => 644,
		notify => Class ["varnish::service"]
	}
 
	file { "/etc/varnish/default.vcl":
		source  => "puppet:///modules/varnish/default.vcl"
	}
 
	file { "/etc/sysconfig/varnish":
		source  => "puppet:///modules/varnish/varnish"
	}
}
 
class varnish {
	include varnish::repo, varnish::install, varnish::service, varnish::conf
}

Install Varnish CentOS 6

CentOS 6 Puppet Install

George Rushby — Wed, 28 Mar 2012 12:51:05 +0000

[ How2CentOS ]

In this tutorial we’ll be covering the very basics of installing and configuring Puppet. Puppet is a system for automating system administration tasks. Its automation saves you countless hours of frustration, monotony and reinventing the wheel. It lets you perform administrative task from a central systems to any number of systems running any variant of operating system.

For a more complete description visit Puppet Labs.

Installing the Puppet CentOS 6 packages

Install the Puppet Repository

rpm -ivh http://yum.puppetlabs.com/el/5/products/i386/puppetlabs-release-5-6.noarch.rpm

Install the EPEL x86_64 YUM Repository

# rpm -Uvh http://download.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-7.noarch.rpm

Install the Puppet Master packages

# yum install puppet-server

Install the Puppet Client packages

# yum install puppet

A Simple Manifest: Managing Ownership of a File

Step 1: Create a minimal manifest file called site.pp in /etc/puppet/manifests with the following content:

# vi /etc/puppet/manifests/site.pp

# /etc/puppet/manifests/site.pp
 
import "classes/*"
 
node default {
    include sudo
 }

Step 2: Next create the sudo.pp class in /etc/puppet/manifests/classes/ with the following content:

# vi /etc/puppet/manifests/classes/sudo.pp

# /etc/puppet/manifests/classes/sudo.pp
 
class sudo {
    file { "/etc/sudoers":
        owner => "root",
        group => "root",
        mode  => 440,
    }
}

This class which will ensure that the owner, group, and mode of the /etc/sudoers file will be set consistently across all systems that belong to that class.

Step 3: Start the Puppet Master service and enable startup on boot

# service puppetmaster start
# chkconfig puppetmaster on

Configuring Puppet

Configure the puppet client to connect to the server and enable logging. Edit the file /etc/sysconfig/puppet and uncomment the PUPPET_LOG and PUPPET_SERVER line specifying the servers address.

# vi /etc/sysconfig/puppet

# The puppetmaster server
PUPPET_SERVER=PuppetMaster
 
# If you wish to specify the port to connect to do so here
#PUPPET_PORT=8140
 
# Where to log to. Specify syslog to send log messages to the system log.
PUPPET_LOG=/var/log/puppet/puppet.log
 
# You may specify other parameters to the puppet client here
#PUPPET_EXTRA_OPTS=--waitforcert=500

The client will automatically pull configuration from the server every 30 minutes, start it as a service and enable startup on boot

# service puppet start
# chkconfig puppet on

Sign the SSL key request from the Puppet Client

In order for the two systems to communicate securely we need to create signed SSL certificates. You should be logged into both the Puppet Master and Puppet machines for this next step.

# puppetca --list
server2.example.co.za

# puppetca --sign server2.example.co.za
Signed server2.example.co.za

+George Rushby

CentOS 6 Puppet Install

Install Percona XtraDB Cluster on CentOS 6.2

George Rushby — Fri, 23 Mar 2012 19:04:44 +0000

[ How2CentOS ]

Percona XtraDB Cluster is a new high availability and high scalability solution for MySQL users. XtraDB Cluster integrates Percona Server with the Galera library of high availability solutions in a single product package. Percona XtraDB is an enhanced version of the InnoDB storage engine for MySQL and MariaDB. It has much faster performance than InnoDB and better scalability on modern hardware.

This tutorial is how to setup a 3-node XtraDB cluster, assuming you are running CentOS Linux 6.2 64-bit.

Install Percona’s CentOS 6 repositories:

# rpm -Uhv http://repo.percona.com/testing/centos/6/os/noarch/percona-testing-0.0-1.noarch.rpm
# rpm -Uhv http://www.percona.com/downloads/percona-release/percona-release-0.0-1.x86_64.rpm

Install Percona XtraDB Cluster packages:

# yum install Percona-XtraDB-Cluster-server Percona-XtraDB-Cluster-client

XtraDB Cluster requires a couple of TCP ports to operate. Easiest way:

# service iptables stop

If you want to open only specific ports, you need to open 3306, 4444, 4567, 4568 ports.

For example for 4567 port (substitute 10.0.0.1 by your IP):

# iptables -A INPUT -i eth0 -p tcp -m tcp –source 10.0.0.1/24 –dport 4567 -j ACCEPT

Now repeat on all XtraDB cluster nodes

Create /etc/my.cnf files

On the first XtraDB Cluster node (assume IP 10.0.0.10):

[mysqld]
datadir=/mnt/data
user=mysql
 
binlog_format=ROW
 
wsrep_provider=/usr/lib64/libgalera_smm.so
 
wsrep_cluster_address=gcomm://
 
wsrep_slave_threads=2
wsrep_cluster_name=trimethylxanthine
wsrep_sst_method=rsync
wsrep_node_name=node1
 
innodb_locks_unsafe_for_binlog=1
innodb_autoinc_lock_mode=2

On the second XtraDB Cluster node:

[mysqld]
datadir=/mnt/data
user=mysql
 
binlog_format=ROW
 
wsrep_provider=/usr/lib64/libgalera_smm.so
 
wsrep_cluster_address=gcomm://10.0.0.10
 
wsrep_slave_threads=2
wsrep_cluster_name=trimethylxanthine
wsrep_sst_method=rsync
wsrep_node_name=node2
 
innodb_locks_unsafe_for_binlog=1
innodb_autoinc_lock_mode=2

On the third XtraDB Cluster node:

[mysqld]
datadir=/mnt/data
user=mysql
 
binlog_format=ROW
 
wsrep_provider=/usr/lib64/libgalera_smm.so
 
wsrep_cluster_address=gcomm://10.0.0.10
 
wsrep_slave_threads=2
wsrep_cluster_name=trimethylxanthine
wsrep_sst_method=rsync
wsrep_node_name=node3
 
innodb_locks_unsafe_for_binlog=1
innodb_autoinc_lock_mode=2

Start mysqld on the first node:

# service mysql start

When all nodes are in SYNCED stage your cluster is ready!

Connect to database on any node and create database:

# mysql
> CREATE DATABASE how2centos_test;

The new database will be propagated to all nodes.

Install Percona XtraDB Cluster on CentOS 6.2

Download CentOS 6.2 iso

George Rushby — Sat, 04 Feb 2012 17:10:19 +0000

[ How2CentOS ]

CentOS 6.2 Downloads

You can download CentOS 6.2 via the web/ftp server or via BitTorrent (recommended) client.

CentOS 6.2 DVD ISO downloads

Download CentOS 6.2 32 bit DVD ISO CentOS-6.2-i386-bin-DVD1.iso and CentOS-6.2-i386-bin-DVD2.iso
Download CentOS 6.2 64 bit DVD ISO CentOS-6.2-x86_64-bin-DVD1.iso and CentOS-6.2-x86_64-bin-DVD2.iso

CentOS 6.2 DVD ISO Torrents

Torrent files for the DVD’s are available at the following location:

Download CentOS 64 i386 torrent file
Download CentOS 64 x86_64 torrent file

Download CentOS 6.2 iso

CentOS Warning: RPMDB altered outside of yum

George Rushby — Tue, 03 Jan 2012 12:07:47 +0000

[ How2CentOS ]

Yum is an automatic updater and package installer/remover for rpm-based systems. It automatically computes dependencies and figures out what things should occur in order to safely install, remove, and update rpm packages. Yum also efficiently and easily retrieves information on any package installed or available in a repository to the installer.

When trying to update your server via the yum command you might see the following error / warning message:

Warning: RPMDB altered outside of yum.

# yum install nethogs
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirror.cogentco.com
* epel: mirror.cogentco.com
* extras: mirror.vcu.edu
* ius: mirror.rackspace.com
* updates: centos.aol.com
Setting up Install Process
Resolving Dependencies
–> Running transaction check
—> Package nethogs.x86_64 0:0.8.0-1.el6 set to be updated
–> Finished Dependency Resolution

Dependencies Resolved
====================================================================
 Package       Arch            Version          Repository     Size
====================================================================
Installing:
 nethogs      x86_64           0.8.0-1.el6      epel          28 k

Transaction Summary
====================================================================
Install       1 Package(s)
Upgrade       0 Package(s)
Total download size: 28 k
Installed size: 53 k
Is this ok [y/N]: y
Downloading Packages:
nethogs-0.8.0-1.el6.x86_64.rpm | 28 kB 00:00
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction

Warning: RPMDB altered outside of yum.

Installing : nethogs-0.8.0-1.el6.x86_64 1/1

Installed:
nethogs.x86_64 0:0.8.0-1.el6

Complete!

How do you fix this problem?

# yum clean all

+George Rushby

CentOS Warning: RPMDB altered outside of yum