Jmeter is basically used for load testing of web applications.

JMeter is to first download the latest production release and install it. The release contains all of the files you need to build and run most types of tests, e.g. Web (HTTP/HTTPS), FTP, JDBC, LDAP, Java, and JUnit.

If you want to perform JDBC testing, then you will, of course, need the appropriate JDBC driver from your vendor. JMeter does not come with any JDBC drivers.

If you want to install the jmeter on your linux box you need to follow my steps

1) Goto http://jakarta.apache.org/site/downloads/downloads_jmeter.cgi
2) Download Binary 2.3.4.zip . The zip file name will be “jakarta-jmeter-2.3.4″
3) Paste it in /var/www/html/
4) Unzip “jakarta-jmeter-2.3.4″
5) New folder with name “jakarta-jmeter-2.3.4″ will be created
6) Go to command prompt
7) go to “jakarta-jmeter-2.3.4″ folder (cd /var/www/html/jakarta-jmeter-2.3.4)
go to “bin” folder (cd bin)
9) Now you are in bin folder (i.e /var/www/html/jakarta-jmeter-2.3.4/bin/)
10) type the command “sh jmeter”
11) After a short pause, the JMeter GUI should appear.

After this you can use following commands for load testing.

For non-interactive testing, you may choose to run JMeter without the GUI. To do so, use the following command options

-n This specifies JMeter is to run in non-gui mode

-t [name of JMX file that contains the Test Plan].

-l [name of JTL file to log sample results to].

-r Run the test in the servers specified by the JMeter property “remote_hosts”

-R [list of remote servers] Run the test in the specified remote servers

The script also lets you specify the optional firewall/proxy server information:

-H [proxy server hostname or ip address]
-P [proxy server port]

Example : jmeter -n -t my_test.jmx -l log.jtl -H my.proxy.server -P 8000

Now these days keeping www in URL is becoming old fashion. How can check many websites for that and the current example is twitter.com

I specially dont like to put www in URL so we can easily remove the www from URL.

Open your apache configuration file. If you are using Linux then open file from following location

# vim /etc/httpd/conf/httpd.conf

put following lines in your virtual directory section.

# remove www from url
RewriteCond %{HTTP_HOST} ^www\.example\.com$ [NC]
RewriteRule ^.*$ http://example.com%{REQUEST_URI} [R=301,L]

We can use this rewrite rule in .htaccess file also. But make sure .htaccess is enable through apache server.

# remove the www from URL.
Options +FollowSymlinks
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www\.example\.com$ [NC]
RewriteRule ^.*$ http://example.com%{REQUEST_URI} [R=301s,L]

For WordPress websites for seo purpose putting above lines in .htaccess file is really best. That will gives you the really great result in future.

In now day many times we heard about cloud hosting and cloud computing. Recently we heard from Matt (WordPress founder) also. Many web designers are not aware with cloud hosting.

In this article I am going to write about in detail about cloud hosting. We are heard about messaging servers and big web services.

Twitter is the biggest mirco blogging website in the world and they are running like more then 100 mongrel server instances on Nginx server for handling the twitter. But still they are facing lot of traffic issue. May be there are multiple reasons. But still one of that is Rails. How much requests single mongrel instance can handle and if they got billions of hits in single second. What will happen we never no.

Who are in server administration they will defiantly have good idea about these issues.

What is cloud hosting?

Cloud hosting is nothing but multiple virtual machines which are basically does load balancing.

Generally, website hosted on a cloud hosting operates on a clustered servers where online operations are not limited to a single server. By handling security, load balance and hardware resources virtually, the website has access to the processing power of a number of servers that are distributed in real time.

Cloud computing is a way of computing, via the Internet, that broadly shares computer resources instead of having a local personal computer handle specific applications.

I can say Cloud hosting is solution for multiple dedicated servers. Handling multiple dedicated server is really pain. So for high traffic websites choosing the cloud hosting is the best option.

Google, Yahoo, MSN, Facebook many companies are already using the cloud hosting for better performance.

For choosing the cloud hosting there are few good options present in market. Some of few as follows:

1. Amazon

2. gogrid

Just use following code in apache configuration file or .htaccess file.

If you are using the shared hosting then please go with only .htaccess file.

Just copy paste following code in .htaccess file.

<IfModule mod_rewrite.c>

Options +FollowSymlinks

RewriteEngine On

RewriteBase /

RewriteCond %{HTTP_HOST} !^www\.wordpressapi\.com$ [NC]

RewriteRule ^(.*)$ http://www.wordpressapi.com/$1 [L,R=301]

</IfModule>

You can download Aapache activeMQ from following URL;

http://activemq.apache.org/activemq-530-release.html

Choose the your OS(Linux/Windows). After downloading apache-activemq-5.3.0-bin.zip.
Extract the ActiveMQ. Open command prompt and go to activeMQ/bin directory and run the “activemq” command.

ActiveMQ will start without configration.
If you are running ActiveMQ on local machine than you can open the ActiveMQ’s Admin from following URL;
http://0.0.0.0:8161/admin/ (8161 is default port)

If you want to run ActiveMQ with XML file. Use following command
#bin/activemq xbean:file:../config.xml

For more information Please visit the http://activemq.apache.org/

Just use following commands
[root@localhost siwan]# yum install openssl
[root@localhost siwan]# yum install openssl-devel
[root@localhost siwan]# yum install mod_ssl

This will start apache server.
[root@localhost siwan]# /etc/init.d/httpd restart

The hosts file is a computer file used by an operating system to map hostnames to IP addresses.
On many operating systems, the host file content is used preferentially over other methods,
such as the Domain Name System (DNS). Unlike DNS, the hosts file is under the control of the local computer’s administrator

Locate the file “Hosts” on your computer:
Windows
Windows 95/98/Me c:\windows\hosts
Windows NT/2000/XP Pro c:\winnt\system32\drivers\etc\hosts
Windows XP Home c:\windows\system32\drivers\etc\hosts

Linux
/etc/hosts or /etc/host.conf or /etc/nsswitch.conf

Symbian
C:\system\data\hosts

Mac OS
/private/etc/hosts or /etc/hosts

In that file you can edit entry like this

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost localhost yourlocaldomain.com , example.com
::1 localhost6.localdomain6 localhost6
192.168.2.200 intranet

directory.example.com 71.155.186.91

First install the following gems:
#su
#gem install mongrel
#gem install mongrel_cluster
#cd project_name
#mongrel_rails cluster::configure -e production -p 3000 -N 3 -c /home/siwan/project_name -a 127.0.0.1 —-prefix /project_name
# mongrel_rails cluster::start

You are able to start your applicaton at http://127.0.0.1:3000, http://127.0.0.1:3001 and http://127.0.0.1:3002

for all the cluster
# mongrel_rails cluster::stop

Advanced prepairation for production realeaze
$ mkdir /etc/mongrel_cluster

#vim /etc/mongrel_cluster/project_name.yml
copy and paste following text;
user: project_name
cwd: //home/siwan/project_name
log_file: /home/siwan/project_name/mongrel.log
port: “3000″
environment: production
group: dev
address: localhost
pid_file: /home/siwan/project_name/tmp/pids/mongrel.pid
servers: 3

or you can run the following command

or copy and paste the content from config/mongrel_cluster.yml file to /etc/mongrel_cluster/project_name.yml

# ln -s /home/siwan/project_name/config/mongrel_cluster.yml /etc/mongrel_cluster/project_name.yml

Then open your httpd.conf file for apache configration:

<Proxy balancer://project_name>
BalancerMember http://127.0.0.1:3000
BalancerMember http://127.0.0.1:3001
BalancerMember http://127.0.0.1:3002
</Proxy>

<VirtualHost *:80>
ProxyPreserveHost On
# Avoid open you server to proxying
ProxyRequests Off
# Options +FollowSymLinks
RewriteEngine On

RewriteRule ^/(images|stylesheet|javascript|html)/?(.*) /home/siwan/project_name/public/$0 [L]
ServerAdmin siwan@yahoo.co.in
DocumentRoot /home/project_name/
ServerName example.com
RewriteRule  ^/(.*)$  balancer://project_name%{REQUEST_URI} [P,QSA,L]
</VirtualHost>

Restart the apache server
#/etc/init.d/httpd restart

Command for restart the mongrel servers from any where
# mongrel_rails cluster::restart -C /etc/mongrel_cluster/project_name.yml

When I restarted my apache server. I am using the fedora 9 here.

I did not get my default page opened in browser.
When I opened the apache error log file. I saw following error.

ModSecurity: Access denied with code 400 (phase 2). Pattern match “%0[ad]” at REQUEST_HEADERS:Cookie. [id "950910"] [msg "HTTP Response Splitting Attack. Matched signature <%0a>"] [severity "ALERT"] [hostname "localhost"] [uri "/"] [unique_id "SuWoGH8AAAEAAFF3rKEAAAAA"]

I after doing some R&D but I did not got any perfect soluction.
Then I cleared the whole browser cookies. That solves my problem.

solution – clear the browser cookies…

When I tried to run my one of my project on server I got following error on the Browser.:

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, root@localhost and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

When I got above error I opened the error log file.

Error Log File log(#vim /var/log/httpd/error_log)
[Wed Oct 14 12:02:56 2009] [notice] mod_python: Creating 4 session mutexes based on 256 max processes and 0 max threads.
[Wed Oct 14 12:02:56 2009] [notice] mod_python: using mutex_directory /tmp
[Wed Oct 14 12:02:56 2009] [notice] Apache/2.2.9 (Unix) DAV/2 PHP/5.2.6 mod_python/3.3.1 Python/2.5.1 mod_ssl/2.2.9 OpenSSL/0.9.8g mod_perl/2.0.4 Perl/v5.10.0 configured — resuming normal operations
[Wed Oct 14 12:02:59 2009] [alert] [client 127.0.0.1] /var/www/html/your_domain_name/.htaccess: DirectoryIndex not allowed here, referer: http://your_domain_name.org/
[Wed Oct 14 12:03:29 2009] [alert] [client 127.0.0.1] /var/www/html/your_domain_name/.htaccess: DirectoryIndex not allowed here, referer: http://your_domain_name.org/
[Wed Oct 14 12:11:13 2009] [notice] caught SIGTERM, shutting down
[Wed Oct 14 12:11:13 2009] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Wed Oct 14 12:11:13 2009] [notice] Digest: generating secret for digest authentication …
[Wed Oct 14 12:11:13 2009] [notice] Digest: done

At the end of file I saw above error.

When I saw that I opened the httpd.conf file and I searched for line.

AllowOverride None

I commented this line.
#AllowOverride None

Then I added following lines to that tag
Order allow,deny
Allow from all

Then I saved the httpd.conf file and restarted the apache server.

This solved the my issue.