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Posts Tagged ‘Cloud’

Make your websites run faster, automatically — try mod_pagespeed for Apache

Google just released the first stable version of mod_pagespeed, the company’sopen-source module for Apache that can automatically optimize your  web pages to improve download and rendering speeds. With this release, Google is declaring this tool ready for broader adoption, though it’s worth noting that a number of large hosting providers like DreamHost, Go Daddy and content delivery network EdgeCast have already been using it in production for quite a while now.

“mod_pagespeed” speeds up your site and reduces page load time. This open-source Apache HTTP server module automatically applies web performance best practices to pages, and associated assets (CSS, JavaScript, images) without requiring that you modify your existing content or workflow.


1. Automatic website and asset optimization

2. Latest web optimization techniques

3. 40+ configurable optimization filters

4. Free, open-source, and frequently updated

5. Deployed by individual sites, hosting providers, CDN’s

How does mod_pagespeed speed up web-sites?

“mod_pagespeed” improves web page latency and bandwidth usage by changing the resources on that web page to implement web performance best practices. Each optimization is implemented as a custom filter in mod_pagespeed, which are executed when the Apache HTTP server serves the website assets. Some filters simply alter the HTML content, and other filters change references to CSS, JavaScript, or images to point to more optimized versions.

“mod_pagespeed” implements custom optimization strategies for each type of asset referenced by the website, to make them smaller, reduce the loading time, and extend the cache lifetime of each asset. These optimizations include combining and minifying JavaScript and CSS files, inlining small resources, and others. mod_pagespeed also  dynamically optimizes images by removing unused meta-data from each file, resizing the images to specified dimensions, and re-encoding images to be served in the most efficient format available to the user.

“mod_pagespeed” ships with a set of core filters designed to safely optimize the content of your site without affecting the look or behavior of your site.   In addition, it provides a number of more advanced filters which can be turned on by the site owner to gain higher performance improvements.

“mod_pagespeed” can be deployed and customized for individual web sites, as well as being used by large hosting providers and CDN’s to help their       users improve performance of their sites, lower the latency of their pages, and decrease bandwidth usage.

Installing mod_pagespeed on CentOS (cPanel/WHM)

  1. root@server1# cd /usr/src 
  2. root@server1[/usr/src]# mkdir mod_pagespeed/
  3. root@server1[/usr/src]# cd mod_pagespeed
  4. root@server1[/usr/src/mod_pagespeed]# wget https://dl-ssl.google.com/dl/linux/direct/mod-pagespeed-beta_current_x86_64.rpm
  5. root@server1[/usr/src/mod_pagespeed]# rpm2cpio mod-pagespeed-beta_current_x86_64.rpm | cpio -idmv
  6. root@server1[/usr/src/mod_pagespeed]# cp usr/lib/httpd/modules/mod_pagespeed.so /usr/local/apache/modules
  7. root@server1[/usr/src/mod_pagespeed]# chmod 755 /usr/local/apache/modules/mod_pagespeed.so
  8. root@server1[/usr/src/mod_pagespeed]# mkdir -p /var/mod_pagespeed/{cache,files} —–> Create pagespeed directories.
  9. root@server1[/usr/src/mod_pagespeed]# chown nobody:nobody /var/mod_pagespeed/*
  10.  root@server1[/usr/src/mod_pagespeed]# /usr/local/apache/bin/apxs -c -i /home/cpeasyapache/src/httpd-2.2.22/modules/filters/mod_deflate.c  —-> Enable mod_deflate (required for mod_pagespeed)
  11. root@server1[/usr/src/mod_pagespeed]# vim /usr/local/apache/conf/pagespeed.conf —>edit the mod_pagespeed configuration file

In this file include    

                                  1. LoadModule pagespeed_module modules/mod_pagespeed.so

                                  2. LoadModule deflate_module modules/mod_deflate.so

                                  3. ModPagespeedFileCachePath “/var/mod_pagespeed/cache/”

                                  4. ModPagespeedGeneratedFilePrefix “/var/mod_pagespeed/files/”

And then open /usr/local/apache/conf/includes/pre_main_global.conf and add:

Include conf/pagespeed.conf

# Rebuild Apache config and restart apache.


/etc/init.d/httpd restart

Once your web server fires up, it’ll be mod_pagespeed-enabled.

You can verify it by using any web-page test tool. Here I am using Pingdom tool. I have share the screenshots of with and without mod_pagespeed module.


Website without mod_pagespeed module



Website with mod_pagespeed module





DevOps on EC2 using Capistrano

DevOps is the combination of development and operation processes. Cloud with your DevOps offers some fantastic properties. The ability to leverage all the advancements made in software development around repeatability and testability with your infrastructure. The ability to scale up as need be real time and among other things being able to harness the power of self healing systems.

The process piece of devops is about taking the principles behind Agile to the entire continuous software development process. The obvious step is bringing Agile ideas to the operations team, which is sorely needed. Traditionally in the enterprise, the application development team is in charge of gathering business requirements for a software program and writing code. The development team tests their program in an isolated development environment for quality assurance which is later handed over to the operations team. The operations team is tasked with deploying and maintaining the program. The problem with this paradigm is that when the two teams work separately, the development team may not be aware of operational roadblocks that prevent the program from working as anticipated.


Capistrano is a developer tool for running scripts on multiple servers, mainly used for deploying web applications on to the servers. It is typically installed on a workstation, and used to deploy code from your source code management to one, or more servers. Capistrano is originally called “SwitchTower”, the name was changed to Capistrano in March 2006 because of some trademark conflict. It is a time saving command line tool and it is very useful to AWS/EC2 servers because we can deploy the code to 1000’s of aws servers by using a single command. For the security of servers we are commonly using aws ssh key authentication. In capistrano  we use this aws ssh key to deploy the web applications to the aws servers.

In Cloud Computing, deploying applications to production/live servers is always a delicate task. The whole process needs to be quick to minimize downtime. Automating the deployment process helps running repetitive tasks minimizing the possibility human error. It is also a good idea to have a proven and easy way to rollback to a previous version if something goes wrong.

It is a standalone utility that can also integrate nicely with Rails. We simply provide Capistrano with a deployment “recipe” or “formula” that describes our various servers and their roles. It is a single-command deployment. it even allows us to roll a bad version out of production and it revert back to the previous release very easily.

Capistrano Deployment

The main functionality of the Capistrano is to Deploy the rails application which we have already developed and we are using the “SVN” or “GIT” to manage the code. It will transfer all the files of our rails application which we have developed in our local host to aws servers directly by simply executing a simple command in our command prompt.

Steps to deploy a rails application

[shell]gem install capistrano[/shell]

Now,we need to capistranize our rails application using the following commands

[shell]capify .[/shell]

It will create two files


capfile .


How to set up deploy.rb file


require ‘rubygems’
require ‘activesupport’
set :application, “<application name>”
set :scm_username/ “<username>”
set :use_sudo, false
set :repository, “http://#{scm_username}@www.example.com/svn/trunk”
set :deploy_to, “/var/www/#{application}”
set :deploy_via, :checkout
set :scm, :git
set :user, “root”
role :app, “<domain_name>”
role :web, “<domain_name>”
rold :db, “<domain_name>”, :primary => true
namespace :migrations do
desc “Run the Migrations”
task :up, :roles => :app do
run “cd #{current_path}; rake db:auto:migrate;”
task :down, :roles => :app do
run “cd #{current_path}; rake db:drop; rake



scm_username’ is your user name
application’ is an arbitrary name you create to identify your application on the server
use_sudo’ specifies to capistrano that it does not need to append ‘sudo’ before all the commands it will run
repository’ identifies where your subversion repository is located

If we aren’t deploying to server’s default path, we need to specify the actual location by using the ‘deploy_to’ variable as given below

set :deploy_to, “/var/www/#{application}”
set :deploy_via, :checkout

If we are using the git to manage our source code, specify the SCM by using the ‘scm’ variable as given below

set :scm, :git
set :user, “root”
role :app, “<domain_name>”
role :web, “<domain_name>”
rold :db, “<domain_name>”, :primary => true

Since most rails users will have the same domain name for their web,app and database, we can simply use our domain variable we set earlier.

namespace :migrations do
desc “Run the Migrations”
task :up, :roles => :app do
run “cd #{current_path}; rake db:auto:migrate;”
task :down, :roles => :app do
run “cd #{current_path}; rake db:drop; rake


After completion of our settings in the deploy.rb file, we need to commit the application by using “svn commit” command if we use svn.

Then we need to run the following command:


cap deploy:setup


It is used to create the directory structure in server.

[shell]cap deploy:check[/shell]

It checks all the dependencies/things like directory permission and necessary utilities to deploy the application by using capistrano.

If everything is successful, you should see a message like:
You appear to have all necessary dependencies installed
And finally deploy the application by using the following command:

[shell]cap deploy[/shell]

Command finished successfully

To Clean up the releases directory, leaving the five most recent releases

[shell]Cap cleanup[/shell]

Prints the difference between what was last deployed, and what is currently in our repository

[shell]cap diff_from_last_deploy[/shell]

To Rolls back to the previously deployed version

[shell]cap deploy:rollback:code[/shell]

Amazon’s EC2 cloud cuts the requisition time of the order & delivery stages down to just minutes. This is already a 75% savings in deployment time! But, without automated deployment, you’ll still need a week to get your application installed.

SSL for Tomcat on AWS EC2

To launch an AWS/EC2 instance, at first setting up a security group to specify what network traffic is allowed to reach the instance. Then select an AMI and launch an instance from it. And create a volume in the same zone of the instance and attach with it. Format the device and mount it to a directory. After that follow the steps to create SSL for Tomcat:

1. For the tomcat we need java, so create a directory to save the Java Binary file.

[shell] mkdir /usr/java
cd /usr/java [/shell]

2. Download jdk binary file (jdk-x-linux-ix.bin) here
Use URL http://www.oracle.com/technetwork/java/archive-139210.html

3. Execute the Binary file

[shell] /usr/java/jdk-x-linux-ix.bin [/shell]

Now we have the Java in our device. Then Download the Tomcat and install it followed by the instructions:-

1. Create a directory to save the tomcat

[shell] mkdir /usr/tomcat
cd /usr/tomcat [/shell]

2. Download tomcat source file (apache-tomcat-x.tar.gz) here
Use URL http://apache.hoxt.com/tomcat/tomcat-6/v6.0.32/bin/

3. Extract that file

[shell] tar -zxvf apache-tomcat-x.tar.gz [/shell]

4. Edit the catalina.sh file

[shell] vim /usr/tomcat/apache-tomcat-x/bin/catalina.sh [/shell]


#** Add at the top **


save and exit
5. Start the tomcat

[shell] /usr/tomcat/apache-tomcat-x/bin/startup.sh [/shell]

6. We can see the logs by using the given command

[shell]tail -f /usr/tomcat/apache-tomcat-x/logs/catalina.out [/shell]

7. Take the browser and enter the URL http://localhost
Now we can see the tomcat index page

8. To stop the tomcat

[shell]/usr/tomcat/apache-tomcat-x/bin/shutdown.sh [/shell]

Now configure the SSL Certificate for tomcat. When you choose to activate SSL on your web server you will be prompted to complete a number of questions about the identity of your website and your company. Your web server then creates two cryptographic keys – a Private Key and a Public Key. The Public Key does not need to be secret and is placed into a Certificate Signing Request (CSR) – a data file also containing your details.

Create a self signed certificate authority (CA) and keystore.

1. Make a directory to hold the certs and keystore. This might be something like:

[shell] mkdir /usr/tomcat/ssl
cd /usr/tomcat/ssl [/shell]

2. Generate a private key for the server and remember it for the next steps

[shell]openssl genrsa -des3 -out server.key 1024[/shell]

Generating RSA private key, 1024 bit long modulus
e is 65537 (0x10001)
Enter pass phrase for server.key:
Verifying – Enter pass phrase for server.key:

3. Generate a CSR (Certificate Signing Request). Give the data after executing this command

[shell]openssl req -new -key server.key -out server.csr[/shell]

Enter pass phrase for server.key:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter ‘.’, the field will be left blank.
Country Name (2 letter code) [GB]:
State or Province Name (full name) [Berkshire]:
Locality Name (eg, city) [Newbury]:
Organization Name (eg, company) [My Company Ltd]:
Organizational Unit Name (eg, section) []:
Common Name (eg, your name or your server’s hostname) []:
Email Address []:

Please enter the following ‘extra’ attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:

4. Remove the passphrasse from the key

[shell]cp server.key server.key.org
openssl rsa -in server.key.org -out server.key[/shell]

Enter pass phrase for server.key.org:
writing RSA key

5. Generate the self signed certificate

[shell]openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt[/shell]

Signature ok
subject=/C=GB/ST=Berkshire/L=Newbury/O=My Company Ltd
Getting Private key

You should then submit the CSR. During the SSL Certificate application process, the Certification Authority will validate your details and issue an SSL Certificate containing your details and allowing you to use SSL. Typically an SSL Certificate will contain your domain name, your company name, your address, your city, your state and your country. It will also contain the expiration date of the Certificate and details of the Certification Authority responsible for the issuance of the Certificate.

Create a certificate for tomcat and add both to the keystore

1. Change the path to ssl

[shell]cd /usr/tomcat/ssl[/shell]

2. Create a keypair for ‘tomcat’

[shell]keytool -genkey -alias tom -keyalg RSA -keystore tom.ks[/shell]

Enter keystore password:
Re-enter new password:
What is your first and last name?
What is the name of your organizational unit?
What is the name of your organization?
What is the name of your City or Locality?
What is the name of your State or Province?
What is the two-letter country code for this unit?

Is CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown correct?
[no]: yes

Enter key password for <tom>
(RETURN if same as keystore password):
Re-enter new password:

3. Generate a CSR (Certificate Signing Request) for tomcat

[shell]keytool -keystore tom.ks -alias tom -certreq -file tom.csr[/shell]

Enter keystore password:

4. create unique serial number

[shell]echo 02 > serial.txt[/shell]

5. Sign the tomcat CSR

[shell]openssl x509 -CA server.crt -CAkey server.key -CAserial serial.txt -req -in tom.csr -out tom.cer -days 365[/shell]

Signature ok
Getting CA Private Key

6. Import the server CA certificate into the keystore

[shell]keytool -import -alias serverCA -file server.crt -keystore tom.ks[/shell]

Enter keystore password:
Owner: O=My Company Ltd, L=Newbury, ST=Berkshire, C=GB
Issuer: O=My Company Ltd, L=Newbury, ST=Berkshire, C=GB
Serial number: ee13c90cb351968b
Valid from: Thu May 19 02:12:51 EDT 2011 until: Fri May 18 02:12:51 EDT 2012
Certificate fingerprints:
MD5: EE:F0:69:01:4D:D2:DA:A2:4E:88:EF:DC:A8:3F:A9:00
SHA1: 47:97:72:EF:30:02:F7:82:BE:CD:CA:F5:CE:4E:ED:89:73:23:4E:24
Signature algorithm name: SHA1withRSA
Version: 1
Trust this certificate? [no]: yes
Certificate was added to keystore

7. Add the tomcat certificate to the keystore

[shell]keytool -import -alias tom -file tom.cer -keystore tom.ks[/shell]

Enter keystore password:
Certificate reply was installed in keystore

To configure a secure (SSL) HTTP connector for Tomcat, verify that it is activated in the $TOMCAT_HOME/conf/server.xml file. Edit this file and add the following lines.

Tomcat configuration

1. Edit the given portion of tomcat configuretion file and change the port as 80

[shell]vim /usr/tomcat/apache-tomcat-6.0.13/conf/server.xml[/shell]

[shell]“””””” <Connector port=”8080″ protocol=”HTTP/1.1″
redirectPort=”8443″ /> “”””””

<Connector port=”80″ protocol=”HTTP/1.1″
redirectPort=”8443″ />


2. Add the given portion to server.xml and give your password in the password portion


<Connector port=”443″ protocol=”HTTP/1.1″ SSLEnabled=”true”
maxThreads=”150″ scheme=”https” secure=”true”
clientAuth=”false” sslProtocol=”TLS” />


When you start the Tomcat Your web server will match your issued SSL Certificate to your Private Key. Your web server will then be able to establish an encrypted link between the website and your customer’s web browser.

Start the tomcat with SSL Certificate

1. Restart tomcat


2. Go to https://Public DNS name:443/

Then your browser shows a security issue. Click the Approve button. Then you can enter to the tomcat with your certificate. When a browser connects to a secure site it will retrieve the site’s SSL Certificate and check that it has not expired, it has been issued by a Certification Authority the browser trusts, and that it is being used by the website for which it has been issued. If it fails on any one of these checks the browser will display a warning to the end user letting them know that the site is not secured by SSL.

You are Done !!!