PUPPET INTRODUCTION, INSTALLATION AND
CONFIGURATION
INTRODUCTION:
Puppet is an open source
framework and tools for managing the configuration of the cluster.it is written
in ruby language and it is used to manage the cluster configuration in UNIX,
Linux and windows platform also.
Why we need puppet?
For an example if you have
thousand node in your cluster. You want change the single configuration file
from the entire cluster; it is very tough task because it is taks lots of time
as well as if you make any mistake in the configuration file. The entire
cluster goes in wrong path. so avoid the above problem we need one tool for
doing the above task in Automatically, that tools is puppet and chef.
Who is developed puppet?
Puppet is developed by Luke
kanies and his company. He was working as UNIX system administrator since 1997.
At the time he was facing lots of problem in the configuration management. So
he decided to develop the one software for doing the configuration management
in automatically, that tool is puppet.
How puppet is works?
Puppet is working like a master slave architecture t is consist of two servers
1. Puppet master
2. Puppet agent
Puppet
master:
It is a Heart of puppet. Without
master node we can’t able to do anything in the cluster. so it is a single
point of failure. it is contain the all the configuration of different to
different hosts.
Puppet
Agents:
The puppet agent is installed
in each on every slave nodes. The puppet agent will connect to the puppet
master with regular time interval. The connection between the puppet agent and
puppet master is made by secure encrypted channel with the help of SSL
Every 30 min the puppet agents will go and get the new configuration from
the puppet master. If suppose the agent is already applied the puppet master
configuration it will not do anything.
INSTALLATION OF PUPPET:
Common
for all nodes:
1. # puppet needs epel,rpmforge repository configured for this
2.
#installs the necessary package
$ yum install ruby-shadow ruby
ruby-libs rubygems
Master Node:
1. #installs puppet agent and Puppet
Master
$ yum install puppet
puppet-server facter
note:
1. The package "puppet" contains the
puppet agent
2. The package
"puppet-server" contains the puppet master server
3. The package
"facter" will contain the tool which will act as fetching information about the node.
Slave
Nodes:
1. # installs puppet agent in
the slave node
$ yum install puppet facter
<!-----------------------installation is
over-------------->
Configuring Puppet:
Master Node:
1. Create the configuration file
$ cd /etc/puppet
$ puppetmasterd --genconfig >
puppet.conf
2. Add the below line in the puppet.conf
file
$ vi puppet.conf
[master]
certname=masterhostname
3. Create the directory and create the
site.pp file in this dir
$ mkdir /etc/puppet/manifests
$ touch
/etc/puppet/manifests/site.pp
note:Puppet will not start
without the site.pp file being present
4. Please run this command it will show
the permission error
$ service puppetmaster start
5. Change the permission and ownership
$ ls /var/lib/puppet/
$ cd /var/lib
$ chown puppet:puppet puppet
$ cd puppet
$ chown puppet:puppet *
6. Start the puppet Master in this node:
$ service puppetmaster start
Slave nodes:
1. Add the puppet.conf file
$ cd /etc/puppet
$ vi
puppet.conf
[main]
server=masterhostname
moduledir =
/etc/puppet/modules:/var/lib/puppet/modules
2. # connect slave in master node
$ puppet agent --server=masterhost --no-daemonize --verbose
Note: surely you will get the below message
1.notice: Did not receive certificate
3. # how to solve the above problem
3. a# goto master node:
$ puppetca --list
(This command will show you the agent
certificate requests that are waiting to be signed)
3. b. now the master
will sign the certificate
$ puppetca --sign slavehostname
4. In terminal you will get the below
message
Notice: Finished catalog run in
0.14 seconds
CREATE OUR FIRST CONFIGURATION:
What is manifests in puppet?
manifest is nothing but a name
that puppet Master calls those files which contain the configuration options
for the clients.An important fact to note is that all manifest files will also
have a .pp extension just the same as site.pp file. The manifests is made up of
number components.they are lists in below
1. Resources
– Individual configuration items
2. Files –
Physical files you can serve out to your agents
3. Templates
– Template files that you can use to populate files
4. Nodes –
Specifies the configuration of each agent
5. Classes –
Collections of resources
6. Definitions – Composite collections of
resources
SAMPLE CONFIGURATION MANAGEMENT:
EXAMPLE1: Install the
memcached package from all slave nodes
1.adding the
nodes in master:
1.#go to directory edit the site.pp file
$cd /etc/puppet/manifests
$ vi site.pp
import 'nodes.pp'
2.# create
the nodes.pp file in the
/etc/puppet/manifests directory
$ vi nodes.pp
node 'nn1.host.com' {
include
memcached
}
node
'dn1.host.com' {
include
memcached
}
node
'dn2.host.com' {
include
memcached
}
2.adding
modules(memcached modules)
1# Find your
modulepath
$ puppet --genconfig |grep modulepath
$ cd /etc/puppet/modules
2.# Create a
directory memcached:
$ mkdir memcached
3.# Inside
this, create manifestsand files directories:
$ cd memcached
$ mkdir manifests files
4.In the
manifestsdirectory, create the file init.pp with the following contents
$ vi init.pp
import "*"
5.In the
same directory, create another file memcached.pp with the following contents
$ vi
memcached.pp
class memcached {
package { "memcached":
ensure => installed,
}
file { "/etc/memcached.conf":
source =>
"puppet:///modules/memcached/memcached.conf",
}
service {
"memcached":
ensure =>
running,
enable =>
true,
require
=> [ Package["memcached"],
File["/etc/memcached.conf"]
],
}
}
6.Changing
to the filesdirectory, create the file memcached.conf with the following
contents:
$ vi
/etc/puppet/modules/memcached/files/memcached.conf
-m 64
-p 11211
-u nobody
-l 127.0.0.1
7.Run Puppet
to test the new configuration
puppet agent --test
EXAMPLE 2: Edit the configuration files in slave nodes with in the
help of Augeas
what is Augeas?
Augeas is a tool which aims to
simplify working with different config file formats, by presenting them all as
a simple tree of values. Puppet's Augeas support allows you to create augeas
resources which can make the required config changes intelligently and
automatically.
1.Install Augeas from all slave nodes using puppet
1.#go to directory edit the site.pp file
$cd /etc/puppet/manifests
$ vi site.pp
import 'nodes.pp'
2.# create
the nodes.pp file in the
/etc/puppet/manifests directory
$ vi nodes.pp
node 'nn1.host.com' {
include
augeas
}
node
'dn1.host.com' {
include
augeas
}
node
'dn2.host.com' {
include augeas
}
2.adding
modules(augeas modules)
1# Find your
modulepath
$ puppet --genconfig |grep modulepath
$ cd /etc/puppet/modules
2.# Create a
directory agueas:
$ mkdir agueas
3.# Inside
this, create manifests and files directories:
$ cd agueas
$ mkdir manifests files
4.In the
manifestsdirectory, create the file init.pp with the following contents
$ vi init.pp
import "*"
5.In the
same directory, create another file augeas.pp with the following contents
$ vi augeas.pp
class
augeas {
package { [ "augeas",
"augeas-devel",
"augeas-libs",
]:
ensure => "present"
}
}
6.Run
Puppet to test the new configuration
$ puppet agent --test
3.Enable the Ip forwared 4
1.In the
manifestsdirectory, create the file init.pp with the following contents
$ vi
ipforward.pp
class augeas::ipforward {
augeas {
"enable-ip-forwarding":
context =>
"/files/etc/sysctl.conf",
changes => [
"set net.ipv4.ip_forward
1",
],
}
}
2..# edit
the nodes.pp file in the
/etc/puppet/manifests directory
$ vi nodes.pp
node 'nn1.host.com' {
include
augeas
include
augeas::ipforward
}
node
'dn1.host.com' {
include
augeas
include
agueas::ipforward
}
node
'dn2.host.com' {
include augeas
include
augeas::ipforward
}
3.Run
Puppet to test the new configuration
$ puppet agent --test
