Archive for the ‘Systems/Network Administration’ Category

I’ve been using DevStack for quite a while now. DevStack is a documented shell script from RackSpace Cloud Builders to build complete OpenStack development environments. Would recommend it for any developer trying to get OpenStack up and running with minimum fuss. The complete installation instructions are available at http://devstack.org

Ceph is a free/open source Software distributed file system Ceph’s main goals are to be Posix-compatible, and completely distributed without a single point of failure.

URL: http://ceph.com/

Keystone, the identity and authentication service of OpenStack often relies on MySQL as the back end Database server.

One of the most common errors I have encounted is the MySQL Access denied error. The URL to trouble shoot such kind of errors is http://dev.mysql.com/doc/refman/5.5/en/access-denied.html

Nice presentation from Mirantis on what’s new in OpenStack Folsom.

http://www.slideshare.net/mirantis/slideshare-folsom-qawebinar

“Nine women can’t make a baby in one month”. – Fred Brooks.

Brook’s Law on Wikipedia

Moved my website http://www.vivekcherian.com from Super Dimension Fortress to my own VPS at Linode after the recent repeated cracker attacks on my websites and home workstation.

I am going to cover the basics of Name Based Virtual Hosting using Apache2 running on a Debian GNU/Linux Server.

The advantage of Name Based Virtual hosting is that you can host multiple websites from an Apache2 Web server and all these websites only require one static I.P Address and also the requirement that your domain name should resolve to the I.P Address of your server.

Steps
——-
Step 1:First let us create the document root directories for the virtual domains example.com,example.org and example.net

————————————————–
root@zion:~# mkdir /home/www

root@zion:~# mkdir /home/www/www.example.com
root@zion:~# mkdir /home/www/www.example.com/htdocs
root@zion:~# mkdir /home/www/www.example.com/cgi-bin
root@zion:~# mkdir /home/www/www.example.com/logs

root@zion:~# mkdir /home/www/www.example.net
root@zion:~# mkdir /home/www/www.example.net/htdocs
root@zion:~# mkdir /home/www/www.example.net/logs
root@zion:~# mkdir /home/www/www.example.net/cgi-bin

root@zion:~# mkdir /home/www/www.example.org
root@zion:~# mkdir /home/www/www.example.org/htdocs
root@zion:~# mkdir /home/www/www.example.org/logs
root@zion:~# mkdir /home/www/www.example.org/cgi-bin
——————————————————-
Please note that I have created separate directories for
htdocs,logs,cgi-bin

Step 2: To enable virtual hosts in your Apache 2 Configuration.

For this let us create a file called /etc/apache2/conf.d/virtual.conf and the following content in it.
——————————————
#
# We’re running multiple virtual hosts.
#
NameVirtualHost *
——————————————

3) Create host files in /etc/init.d/sites-available in the following format for example.com

——————————————————–

ServerAdmin webmaster@example.com
ServerName http://www.example.com
ServerAlias example.com

# Indexes + Directory Root.
DirectoryIndex index.html
DocumentRoot /home/www/www.example.com/htdocs/

# CGI Directory
ScriptAlias /cgi-bin/ /home/www/www.example.com/cgi-bin/

Options +ExecCGI

# Logfiles
ErrorLog /home/www/www.example.com/logs/error.log
CustomLog /home/www/www.example.com/logs/access.log combined

——————————————————–

Create similar virtual host files for example.net and example.org

4) Now enable the sites by running the command a2ensite

———————————————————

root@zion:~# a2ensite http://www.example.com
Site http://www.example.com installed; run /etc/init.d/apache2 reload to enable.

root@zion:~# a2ensite http://www.example.net
Site http://www.example.net installed; run /etc/init.d/apache2 reload to enable.

root@zion:~# a2ensite http://www.example.org
Site http://www.example.org installed; run /etc/init.d/apache2 reload to enable.
———————————————————–

This will create a symbolic link between the files for the domains from /etc/init.d/sites-available to /etc/init.d/sites-enabled.

5) Restart apache2 with the command /etc/init.d/apache2 restart.

I was looking for a URL that would help me to list out the the default installation layouts for Apache httpd on various operating systems and distributions.

I found this URL: http://wiki.apache.org/httpd/DistrosDefaultLayout

Thanks to jMCg on #httpd on FreeNode for pointing me to this URL.

I received an email early today morning from The Red Hat Certification Central informing me that I have been awarded a new certification named Red Hat Certified System Administrator.

My new RHCSA certificate number is 100-173-327

I support the Electronic Frontier Foundation in their stand against Internet Censorship.