PENNY (Congstar) USB Internet on Linux Mint 17 - Ubuntu 14.04

So, I've been in Germany for a while. And after using the fast WiFi in hotels, I moved to a personal apartment, with no Internet for now. I bought a PENNY USB surf stick as I thought it is a bit cheaper. But there was a problem, it is not working on Linux :(.

 
I lived with this fact for a while, but now I want to get back to programming. So, after some searching and trying, here is how I could use my PENNY Mobil Internet Stick, without their Internet manager of course, and that's a bit bad for calculating my overall usage.

Anyways, it is straight forward:

1. Open 'Network Connections'. Click 'Add'.

2.  Choose 'Mobile Broadband'.

3. The default device is 'Internetstick'.

4. Choose your country. Mine is 'Germany'.

5. The service provider is 'Congstar'.

6. The default plan is 'Prepaid Contracts', which is my case.

7. Verify your data and click 'Apply'.

8. The connection form is pre-populated with the correct data. I just changed the connection name to be meaningful to me. (and the password was tm)

9. Go to 'IPv4 Settings' tab, and Add this additional DNS server IP: 193.254.160.1. Now click 'Save'.

10. The connection is added. Click 'Close'.

11. Now you can see in the connections list that a broadband section is added. Turn it on it was off. Or click the connection name you just created (Congstar Prepaid PENNY).

Now you are connected. Enjoy the surfing and keep an eye on the System Monitor for data usage :).

Installing Multiple Redis Versions on Ubuntu

Sometimes, for testing purpose as example, a developer needs to install and run different versions of Redis Server for different projects. And since I do not like wasting time on haching config files and pid files, this is the easiest way I use to run the desired Redis Server version.

It is as simple as downloading, compiling, and running the compiled server:

$ wget http://download.redis.io/releases/redis-2.8.9.tar.gz
$ tar xzf redis-2.8.9.tar.gz
$ cd redis-2.8.9
$ make
$ ./redis-server

If the version is older, you may not find it on redis.io. So try a URL like:

http://redis.googlecode.com/files/redis-1.2.6.tar.gz

That's it. Enjoy!

Deploying Rails Application on Windows Azure (Ubuntu VM)

In the last weeks, I've been exploring my options for hosting a Ruby on Rails application. An important step was Windows Azure. I registered for a 90-day trial to give it a try. One of the great services Microsoft has offered was the Ubuntu virtual machine ( :D ). So this tutorial can be useful even with a normal Ubuntu machine (except the Endpoints part) since I'm treating it like an Ubuntu machine regardless of the Azure service it is hosted on.

In this tutorial, I will create a new Ubuntu 12.04 LTS virtual machine, install Ruby ( 1.9.3 ) and Rails ( 3.2.9), install Passenger gem, install Apache server and connect it to Rails application. And finally, some important notes about getting your project up and running.

Create an Ubuntu 12.04 LTS VM:

- In you portal, from the bottom right corner click: New -> Compute -> Virtual Machine -> From Gallery.

- Scroll the list to Ubuntu Server 12.04 LTS and click it.

- Fill the required data about the VM name, the username to create in that machine and password (you will need them A LOT), and number of cores running this machine (I'm on trial version, so 1 is enough to try it).

- Choose the appropriate DNS name (your service URL) and the suitable place for the service.

- You are done with the VM creation.

Create Endpoints for SSH, FTP, Apache:

- The endpoint is the way of communication between the VM and the outer world. Each endpoint takes a public port (the one you call) and a private port (the one the VM listens to).

- Click on the created VM, select the ENDPOINTS tab. You will find that the SSH endpoint is already created on port 22.

- Now create two other ports for FTP (port 21) and Apache service (default port, port 80). Names of the endpoints do not matter, but you'd better give them meaningful names.

- Do not forget to start the VM before the next step.

Access the Ubuntu Server Through SSH:

- All you interaction with the server will be though SSH via port 22. Although you can then install a GUI package and remote access the server, I choose not to do this because of the extra space and CPU cycles it takes, and common, this is Linux, you only need a terminal to have fun!

- Since I'm using windows, I use a nice SSH client: PuTTY. Just download, run, enter your server's name and click 'open', enter usrename/password in the terminal that shows up.

- Now you are on board, let's install Ruby and Rails.

Note: You can copy and paste inside PuTTY terminal as follows: highlight the terminal text with the mouse to copy it, and right click on the terminal to paste.

Install Ruby and Rails:

- Some people prefer to install Ruby using 'rbenv' or 'rvm', but I prefer simplicity. I'll just install Ruby directly.

- If you cannot 'sudo apt-get install ruby -v 1.9.3' directly, you may follow these steps:

sudo apt-get update

sudo apt-get install ruby1.9.1 ruby1.9.1-dev \
  rubygems1.9.1 irb1.9.1 ri1.9.1 rdoc1.9.1 \
  build-essential libopenssl-ruby1.9.1 libssl-dev zlib1g-dev

sudo update-alternatives --install /usr/bin/ruby ruby /usr/bin/ruby1.9.1 400 \
         --slave   /usr/share/man/man1/ruby.1.gz ruby.1.gz \
                        /usr/share/man/man1/ruby1.9.1.1.gz \
        --slave   /usr/bin/ri ri /usr/bin/ri1.9.1 \
        --slave   /usr/bin/irb irb /usr/bin/irb1.9.1 \
        --slave   /usr/bin/rdoc rdoc /usr/bin/rdoc1.9.1

# choose your interpreter
# changes symlinks for /usr/bin/ruby , /usr/bin/gem
# /usr/bin/irb, /usr/bin/ri and man (1) ruby
sudo update-alternatives --config ruby
sudo update-alternatives --config gem

# now try
ruby --version

Then install Rails

sudo gem install rails --no-rdoc --no-ri

Install Passenger and Apache:

- The passenger gem is the connection between Apache server and your rails app. We need to install Passenger, Apache, and the Passenger's Apache module.
(edit: I've been facing some issues with v3 when restarting the server, so I added --pre to install the yet-not-released v4. In case you have v4 by the time you read this, just proceed with the command as it is.)

sudo gem install passenger --no-rdoc --no-ri
sudo passenger-install-apache2-module

- The previous line will open an installation wizard to guide you though the installation of the module. It is supposed to ask you for extra packages to install. In my case, these were the packages:

sudo apt-get install libcurl4-openssl-dev apache2-mpm-prefork apache2-prefork-dev libapr1-dev libaprutil1-dev

- After installing the missing packages, run the module installation one more time.

sudo passenger-install-apache2-module

- Now the module will install and ask you to add some paths to the apache config file which is supposed to be in 'etc/apache2/apache2.conf'.

- It will also give you an example of how to add a virtual host to get your rails app running through Apache.

- To open the file from terminal, use:

sudo nano etc/apache2/apache2.conf

- Here is what I had to add to my config file:

LoadModule passenger_module /var/lib/gems/1.9.1/gems/passenger-3.0.18/ext/apache2/mod_passenger.so
PassengerRoot /var/lib/gems/1.9.1/gems/passenger-3.0.18
PassengerRuby /usr/bin/ruby1.9.1

<VirtualHost *:80>
  ServerName adly-test.cloudapp.net
  # !!! Be sure to point DocumentRoot to 'public'!
  DocumentRoot /home/adly/apps/testrails/public

  <Directory /home/adly/apps/testrails/public>
     # This relaxes Apache security settings.
     AllowOverride all
     # MultiViews must be turned off.
     Options -MultiViews
  </Directory>
</VirtualHost>

Upload Your Project Using FTP:

- Some tutorials go for using Github and some packaging tools, but I do not like that. I want to upload my files myself. So I'm using "vsftpd" for the Ubuntu Server side, and FileZilla on the my Windows side.
(You can use Git without the need to Capistrano or Unicorn gems, remember it is just a Linux machine. Git is better for continuous development.) (you can also use WinSCP client for SFTP protocol and forget about FTP client and end point)

- Install vsftpd

sudo apt-get install vsftpd

- Edit the config file:

sudo nano /etc/vsftpd.conf

- Modify the following lines:

#local_enable=YES

to

local_enable=YES

#write_enable=YES

to

write_enable=YES

anonymous_enable=YES

to

anonymous_enable=NO

- Restart the FTP server

sudo service vsftpd restart

- Now we are done with the server side. On the client side, install FileZilla and open it.

- From "Edit" -> "Settings", make sure the settings are as follows:

- From the main screen, enter your service URL, username, password, and port 21 and click "Quick Connect".

- Now you will have the server folders on the right, and your local files on the left. Move and modify however you want.

Fine tuning to get things working right (do not trust HelloWorld tutorials):

If you create a dummy project using 'rails new testrails', it will probably work fine. But those tutorials do not give the complete case of a real application, so here are some extra steps to do to avoid errors or unknown behavior.

Rails and Apache log file:

- It happens that the Rails app will write to the Apache log file, so it is better to locate a custom path to that log file instead of the default path. I prefer logging errors in a log file in the same directory of Rails log folder. So I add the following line to the VirtualHost configuration in the apache config file. I also prefer declaring the Rails working environment explicitly to avoid any human/machine errors in the future.

ErrorLog /home/adly/apps/testrails/log/error.log
RailsEnv production

so it is now like

LoadModule passenger_module /var/lib/gems/1.9.1/gems/passenger-3.0.18/ext/apache2/mod_passenger.so
PassengerRoot /var/lib/gems/1.9.1/gems/passenger-3.0.18
PassengerRuby /usr/bin/ruby1.9.1

<VirtualHost *:80>
  ServerName adly-test.cloudapp.net
  # !!! Be sure to point DocumentRoot to 'public'!
  DocumentRoot /home/adly/apps/testrails/public
  ErrorLog /home/adly/apps/testrails/log/error.log
  RailsEnv production

  <Directory /home/adly/apps/testrails/public>
     # This relaxes Apache security settings.
     AllowOverride all
     # MultiViews must be turned off.
     Options -MultiViews
  </Directory>
</VirtualHost>

Assets Compilation:

- You have to set this line to true

config.assets.compile = true

in {app_root}/config/environments/production.rb

and do not forget to compile the assets whenever changed:

rake assets:precompile

[check the "ExecJS Error, and libv8 / therubyracer version errors" section at the bottom if you have an error]

DB migration:

- If you have a database in your project, the declaration of "production" environment in the apache config file is not enough, you have to declare it explicitly when migrating:

rake db:migrate RAILS_ENV="production"

FILES PERMISSIONS:

- This is a very important step, since some files are still owned by you with zero permissions to other users.

- The quick and not-so-liberal permission is 755 for all the application folder

sudo chmod -R 755 /path/to/your/app/

- (just in case you face problems later, make this step) Double check that you give rwx privileges to the DB, assets, log and tmp folders for the user running this app whenever you add new files. For example:

sudo chmod -R 755 /path/to/your/app/app/assets
sudo chmod -R 755 /path/to/your/app/db
sudo chmod -R 755 /path/to/your/app/tmp
sudo chmod -R 755 /path/to/your/app/log

- Note: Do not forget to check the permissions of any new file you upload.


ExecJS Error, and libv8 / therubyracer version errors:

- Now this is something very common with a lot of workarounds. It is on Rails 3 because of some compatibility issues. You should get an error like "Could not find a JavaScript runtime. See https://github.com/sstephenson/execjs for a list of available runtimes.".

- To solve this problem, open your Gemfile, and add the following lines under the "group :assets do" section:

gem 'therubyracer', '0.11.0beta8', :platforms => :ruby
gem 'libv8', '~> 3.11.8.3', :platform => :ruby

then do not forget to "bundle install". No need for 'sudo', let the gems be installed locally.

[update: libv8 compilation may take several minutes if there is no matching binary for your OS version and specified version number. On another server I had to change the version to '3.11.8.3' to save time and CPU usage. Click here for more: Installing with native extensions stall ]

One final note: Do not forget to restart Apache server for the changes to take effects.

sudo service apache2 restart

MeeGo 1.2 for Netbooks in Virtualbox ( Windows and Ubuntu )

These are the steps for installing MeeGo 1.2 for Netbooks in Virtualbox. These steps were tested on Ubuntu 10.04 and Windows 7. Steps are the same on both OSs, and screenshots were taken from Ubuntu 10.04.

First, you should download the latest version of MeeGo from: https://meego.com/downloads
and install Virtualbox, whether from : https://www.virtualbox.org/wiki/Downloads or from Ubuntu Software Center.

Second, covert the extension from the downloaded MeeGo image from (*.img) to (*iso).

Then, open Virtualbox and create a new machine.

Make sure you indicate the machine as a Fedora Linux version, with Ram 512MB or higher (MeeGo Wiki says 1GB) and at least 5GB of disk space. Also make sure you enable the options of "Enable PAE/NX" and "Enable 3D Acceleration".

Here are screenshots of this step:

Now let's start our new virtual machine. From the menu appearing, chose "Installation Only", wait until some operations end, then the UI wizard will appear. The steps of installation are almost straight forward. And after installation, A message will say that you should not remove the USB stick (or the virtual CD ROM in our case) until you press the "Close" button. So press "Close" and then un-mount the CD ROM from the Virtualbox menu: Machine -> CD/DVD Devices -> Unmount. Then reboot the machine from: Machine -> Reset.

After restarting, the wizard will continue with some basic settings. When going through these steps, they went fine on Windows 7, but on Ubuntu 10.04 I had to reset the machine a couple of times to finish the settings steps and move to the next step. BTW: The blue splash screen at the beginning of these steps may stay for a few seconds.

Now we come to a little dirty part. At this moment, the machine may start normally without any effort. But some other times you need to do the following steps. These steps are the best I could write after searching and trying for hours:

First wait until the first blue screen appears and press "ESC" on the keyboard. This will view a list with one option to boot MeeGo. Press "Tab" key to edit the command of launching MeeGo, remove the last part of "quite vga=current" and replace it with "init 3" then hit the "Enter" key.

Some commands will appear quickly on the screen, wait until you see the login screen.

Do a login with the username/password you have set in the previous steps. Then write:
sudo su
[enter the password again]
chmod +s /usr/bin/Xorg
uxlaunch

Now you should wait for a few seconds to see the MeeGo home screen appearing.

If you want to shutdown the machine in a legal way, you will notice that there is no "Shutdown" button. But you can still choose "Machine -> ACPI Shutdown" from the virtual machine menubar.

There is another final note: Although I had to write the terminal commands whenever I launch the machine on Windows 7, I found the machine booting normally on Ubuntu 10.04 once I hit the "Start" button.
Update: It booted fine on both OSs. The problem was because I did not make a legal shutdown, so the session was not saved.