If you are running a MacBook Pro, you know they run hot. I solved this issue on the cheap by recycling an iWork Retail Eddition box to allow for more airflow under the the MacBook. All you need is to allow a bit of air to flow on the bottom surface and this box happens to be just the right hight to accomplish with ease.
Over the past few weeks I have been teaching myself ever so slowly Ruby on Rails. While my background is system administration, I have always had an eye for programming logic and a respect for programmers. The first place one needs to start when learning Ruby on Rails is getting up and running Ruby on Rails on the Server or Workstation.
I already have a dedicated Ubuntu Servers so I will leverage what I already have implemented and hook in Ruby on Rails. For my server environment I already have Apache 2, MySQL Server and a few other tools so I will start with that as a baseline. If you don’t have any of this installed already I have created a primer below.
Install Apache Server
sudo apt-get install apache2
After the install, Apache will autostart. As a result you might find an error
* Starting web server apache2 apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName ...done.
While this is annoying, it does not impact Apache’s ability to operate but the fix is simple and resolved by creating a file called fqdn (fully qualified domain name) in /etc/apache2/conf.d/. Mine looks like this:
ServerName localhost
Restarting Apache will now result in a clean startup.
sudo /etc/init.d/apache2 restart
Install Mysql Server
While Ruby runs great with sqlite, I have on my server MySQL as it performs all the needs I have in a shared database environment. Installing is simple and is accomplished with just a few simple commands.
sudo apt-get install mysql-server sudo apt-get install libmysqlclient16-dev
During the install, MySQL will prompt you to create a root password for the admin user.
To test the installation, log in to MySQL via command line to confirm.
doug@audi:~$ mysql -u root -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 34 Server version: 5.0.75-0ubuntu10.2 (Ubuntu) Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql>
And to view the databases
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | +--------------------+ 2 rows in set (0.00 sec) mysql>
Install Ruby from Source
While this solution might promote some argument, I believe by far the best way to work with some applications, including Ruby on Rails is to install from source. This method will give you the most control as well as provide stability when performing system upgrades or during the patching process.
Make a directory for all your source code. This will come in handy when you need to re-compile and add in additional functionality for future efforts.
You may already have a /usr/local/src directory but if you don’t, simply create one for yourself.
sudo mkdir /usr/local/src
We will place all source code for Ruby and RubyGems in this directory.
Download Ruby
cd /usr/local/src
sudo wget ftp://ftp.ruby-lang.org/pub/ruby/1.8/ruby-1.8.7-p174.tar.gz
You need to use sudo with wget in this case because as a normal user, you wont have the necessary permissions to save to this directory.
Uncompress ruby-1.8.7-p174.tar.gz
sudo tar -xzvf ruby-1.8.7-p174.tar.gz cd ruby-1.8.7-p174 sudo ./configure sudo make sudo make install
Ruby is now installed in /usr/local/bin/ruby
While Ruby is installed, there a still 2 pieces that are needed before we install RubyGems.
Install zlib for Ruby
cd /usr/local/src/ruby-1.8.7-p174/ext/zlib sudo ruby extconf.rb --with-zlib-include=/usr/include --with-zlib-lib=/usr/lib sudo make sudo make install
Install openssl for Ruby
cd ../openssl/ sudo ruby extconf.rb sudo make sudo make install
Install RubyGems
cd /usr/local/src/ sudo wget http://rubyforge.org/frs/download.php/60718/rubygems-1.3.5.tgz sudo tar -xzvf rubygems-1.3.5.tgz cd rubygems-1.3.5 sudo ruby setup.rb config sudo ruby setup.rb setup sudo ruby setup.rb install
Install RAILS
sudo gem install rails
You will need to enable RAILS to talk to our database and this is done by installing the mysql gem.
sudo gem install mysql
Optionally, you can install Mongrel instead of using WebBrick.
sudo gem instal mongrel
Install Passenger
Passenger basically allows you to proxy RAILS applications via apache to the Ruby server – WebBrick or Mongrel. The installation is rather easy and is installed via a Ruby gem. Once installed you will need to modify your Apache configurations to point to the appropriate RAILS application.
sudo gem install Passenger sudo passenger-install-apache2-module
After running passenger-install-apache2-module, it said I was missing some dependencies. In my case I needed to install the following via apt-get.
sudo apt-get install build-essential apache2-prefork-dev libapr1-dev libaprutil1-dev
After installing the dependancies, re-run passenger-install-apache2-module.
sudo passenger-install-apache2-module
The passenger configuration requires you to modify your Apache configuration file. In my case I create a file in /etc/apache2/conf.d called passenger.
sudo vi /etc/apache2/conf.d/passenger
LoadModule passenger_module /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.8/ext/apache2/mod_passenger.so PassengerRoot /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.8 PassengerRuby /usr/local/bin/ruby
Then you need to create a virtual host to point to your new application. In my case it is setup in this fashion but there are many other ways of accomplishing the same thing.
sudo vi /etc/apache2/site-available/ruby.dougjaworski.com
What my virtual host file looks like.
< VirtualHost *:80>
ServerAdmin webmaster@localhost
ServerName ruby.dougjaworski.com
DocumentRoot /home/doug/rails_apps/test/public
< Directory /home/doug/rails_apps/test/public>
Options MultiViews
AllowOverride All
< /Directory>
< /VirtualHost>
It is important that you point DocumentRoot to the location of your applications public folder as this is what is exposed to Apache.
It is also important that you have a DNS record or at the very least an entry in hosts host pointing to your Apache virtual host as this is named based resolution.
Now you must enable the virtual host.
sudo a2ensite ruby.dougjaworski.com [sudo] password for doug: Enabling site ruby.dougjaworski.com. Run '/etc/init.d/apache2 reload' to activate new configuration!
Reload the Apache configuration so your changes take effect.
sudo /etc/init.d/apache2 reload
Point your web browser to your new RAILS site!
How to Install MySQL Server on RHEL 5.3
sudo yum install mysql-server mysql
sudo chkconfig –add mysqld
sudo chkconfig –level 2 mysqld
sudo chkconfig –level 3 mysqld
sudo chkconfig –level 4 mysqld
How to Set the MySQL Root User Password
mysql -u root
mysql> SET PASSWORD FOR ‘root’@'localhost’ = PASSWORD(‘yourpassword’);
mysql> FLUSH PRIVILEGES;
mysql> exit
How to Create a Database
mysql -u root -pyourpassword
mysql> CREATE DATABASE yourdatabase;
Creating a User With Access to New Database
mysql -u root -pyourpassword
mysql> GRANT ALL PRIVILEGES ON yourdatabase.* TO ‘yourusername’@'localhost’ IDENTIFIED BY ‘yourpassword’ WITH GRANT OPTION;
mysql> FLUSH PRIVILEGES;
mysql> exit
To Create a User With Fewer Privileges Limited to New Database
mysql -u root -pyourpassword
mysql> GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES ON yourdatabase.* TO ‘yourusername’@'localhost’ IDENTIFIED BY ‘yourpassword’;
mysql> FLUSH PRIVILEGES;
mysql> exit
To Create a User With Access to New Database From any Host
mysql -u root -pyourpassword
mysql> GRANT ALL PRIVILEGES ON yourdatabase.* TO ‘yourusername’@'localhost’ IDENTIFIED BY ‘yourpassword’ WITH GRANT OPTION;
mysql> FLUSH PRIVILEGES;
mysql> exit
To Create a User With Access to database from any host
mysql -u root -pyourpassword
mysql> GRANT ALL PRIVILEGES ON yourdatabase.* TO ‘yourusername’@'%’ IDENTIFIED BY ‘yourpassword’ WITH GRANT OPTION;
mysql> FLUSH PRIVILEGES;
mysql> exit
How to Backup a Database Instance From mysqldump Command
/bin/mysqldump -u username -ppassword –databases databasename >/tmp/databasename.sql
How to Restore a Database Instance From Command Line
mysql -u username -ppassword databasename < /tmp/databasename.sql
If you ever need to copy files across a network and wanted a quick and easy way to do it without FTP, NFS, SAMBA or an other remote directory access solutions. RSYNC is usually part of most Unix or Linux distributions and can be easily installed.
The most basic of options is below:
rsync -avz -e ssh user@remotehost:/path/to/dir /local/dir/
Ever needed to shutdown or restart windows from a remote desktop session? I was wondering this very thing today as my monitor locked up on my Dell E6500 laptop. Since the shutdown or restart feature are not enabled on the start menu in an RDP session, you need to do the following:
CTRL-ALT-END
You will then have the option to restart or shutdown the remote computer.
BIND (Berkley Internet Name Domain) is the most common of all DNS servers and generally a standard on most Linux and UNIX distributions.
For a more detailed look at Bind and its technical history take a look at the Wikipedia article on Bind.
CHROOT is commonly referred to as JAIL and is often used to change the root of an application to another location for the reasons of security. Often times CHROOT is used for services that run under root user and can be insecure so it is a way of protecting the root operating system in the event of an application compromise.
In this HowTo, we will be installing BIND9 and CHROOTing bind to live in an restricted portion of the Linux file system. For the purposes of this HowTo we will be using a running installation of Debian Etch.
Assumptions
1. Bind will be configured as an authoritative DNS master resolving for specific domain names
2. You have limited knowledge of Linux editors such as vi
3. Utilization of Sudo. If you do not use sudo, simply eliminate sudo from any commands however you will need to be logged in as a root user
Install Bind 9
sudo apt-get install bind9
CHROOT Bind 9
sudo /etc/init.d/bind9 stop
Edit /etc/default/bind9 and configure bind to run as an unprivileged user and chrooted to /var/lib/named as follows:
OPTIONS=”-u bind -t /var/lib/named”
# Set RESOLVCONF=no to not run resolvconf
RESOLVCONF=yes
Create the necessary directories /var/lib
sudo mkdir -p /var/lib/named/etc
sudo mkdir /var/lib/named/dev
sudo mkdir -p /var/lib/named/var/cache/bind
sudo mkdir -p /var/lib/named/var/run/bind/run
Move the default bind config directory from /etc to /var/lib/named/etc
sudo mv /etc/bind /var/lib/named/etc
Create a symbolic link to the new config directory form the old location to the new locations
sudo ln -s /var/lib/named/etc/bind /etc/bind
Make null and random devices and set the correct file permissions
sudo mknod /var/lib/named/dev/null c 1 3
sudo mknod /var/lib/named/dev/random c 1 8
sudo chmod 666 /var/lib/named/dev/null /var/lib/named/dev/random
sudo chown -R bind:bind /var/lib/named/var/*
sudo chown -R bind:bind /var/lib/named/etc/bind
Modify syslogd to log to the right location
sudo vi /etc/default/syslogd
Modify the line SYSLOGD=”” so it reads SYSLOGD=”-a /var/lib/named/dev/log”
#
# Top configuration file for syslogd
#
#
# Full documentation of possible arguments are found in the manpage
# syslogd(8).
#
#
# For remote UDP logging use SYSLOGD=”-r”
#
SYSLOGD=”-a /var/lib/named/dev/log”
Restart syslogd and start bind
sudo /etc/init.d/sysklogd restart
sudo /etc/init.d/bind9 start
Check for logs by tailing /var/log/syslog for any error messages
sudo cat /var/log/syslog
or
sudo tail –f /var/log/syslog
Testing
Now that Bind 9 is installed, you will want to test and this can be done with the following command:
dig @localhost www.yahoo.com
Configure Bind 9
The next step is to create a master zone directory followed by a zone template. It is extremely important to be cognizant of file permissions. If you get these wrongs, Bind will not resolve for your domains. Each zone file needs to be owned by the user and group bind. So if you create a new zone make sure to assign the right permissions to the new zone file
sudo mkdir -p /etc/bind/zones
sudo chown bind:bind /etc/bind/zones
sudo chmod 700 /etc/bind/zones
Create a template zone file
sudo vi /etc/bind/zones/template
;
; SOA
;
$TTL 1h
@ IN SOA dns1.example.com. hostmaster.example.com. (
2007010101 ; Serial number
1h ; Slave refresh
15m ; Slave retry
2w ; Slave expire
1h ; Negative Cache TTL
)
;
; NS RECORDS
;
@ IN NS dns1.example.com.
@ IN NS dns2.example.com.
;
; MAIL RECORDS
;
IN MX 10 mx01.example.com.
IN MX 10 mx02.example.com.
;
; MAIL HOSTS
;
mx01 IN A 1.2.3.4
mx02 IN A 1.2.3.4
mail01 IN A 1.2.3.4
mail02 IN A 1.2.3.4
;
; WWW RECORDS
;
@ IN A 1.2.3.4
www IN A 1.2.3.4
blog IN A 1.2.3.4
;
; CUSTOM RECORDS
;
server-a IN A 1.2.3.4
server-b IN A 1.2.3.4
Again, ensure you have the right permissions for the zone file.
sudo chown bind:bind /etc/bind/zones/template
sudo chmod 600 /etc/bind/zones/template
Create a New Zone
Copy the zone file template from above and edit as needed.
sudo cp -p /etc/bind/zones/template db.example.com
At the very minimum the serial number and edit the file as needed.
Next, enable the zone file in /etc/bind/named.local
sudo /etc/bind/named.conf.local
zone “example.com” {
type master;
file “/etc/bind/zones/db.example.com”;
notify yes;
};
Reload Bind and test
sudo tail -f /var/log/syslog
sudo tail -f /var/log/daemon.log
dig @localhost example.com MX
Feel free to contact me with any questions or revisions.
Special thanks to the following sites for contrbuting information:
http://doc.ubuntu.com/ubuntu/serverguide/C/dns-configuration.html
http://www.howtoforge.org/perfect_setup_debian_etch_p4
http://www.besy.co.uk/debian/how_to_setup_a_bind_9_dns_server