Archive for the ‘Ubuntu Linux’ Category

Network Manager Applet NOT Showing in MATE Desktop Taskbar Ubuntu

Saturday, February 13th, 2016

Network Manager Applet NOT Showing in MATE Desktop

If you install the MATE desktop environment on Ubuntu, your Network Manager icon may not show up in the taskbar as shown below:

Without the Network Manager icon showing, you will have a hard time managing and connecting to WIFI networks.  To get it to show up, you will need to edit the following file using nano:

sudo nano /etc/xdg/autostart/nm-applet.desktop

Look for the below line:

AutostartCondition=GNOME3 unless-session gnome

And comment it out like so:

#AutostartCondition=GNOME3 unless-session gnome

Save the file using "Ctrl + O", and then exit nano using "Ctrl + X".  Restart your computer.  The network icon will show up again as shown below:

Note, the actual icon will vary based on the selected MATE desktop theme.  The screenshots above show the icon used in the LUNA theme.

Save iptables on Shutdown and Restart, and Restore on Boot

Tuesday, October 6th, 2015

Save iptables Rules on Shutdown, Restore on Boot

When your server shutsdown (halts), reboots, or enters runlevel 1, your iptables configuration is automatically wiped and reset.  Packages such as iptables-persistent supposedly help with this problem, but unless you save your rules manually, the rules are never saved automatically when the system reboots. 

I've wanted to truly persist my iptables, so I decided to change their package to always save the iptables rules when the system reboots, halts, or enters runlevel 1 automatically.  The rules are then restored when the system boots to runlevels 2-5.  This means that your iptables configuration will persist forever.  This may not be desired, but if I ban an IP address permanently, I always want it to be banned.

If you'd like to use this modified version of iptables-persistent so that your rules are automatically saved on shutdown, you can install it by running the below commands:

sudo apt-get remove iptables-persistent
sudo dpkg -r iptables-persistent
wget http://dinofly.com/files/linux/iptables-persistent_0.5.8_all.deb
sudo dpkg --install iptables-persistent_0.5.8_all.deb

Use at your own risk.  If you do something stupid, it will persist until you can clear it!

The above package was tested in Ubuntu 12.04 x86, Ubuntu 12.04 x64, Ubuntu 14.04 x86, Ubuntu 14.04 x64, and Ubuntu 15.04 x64.  Should work on other debian operating systems as well.

Get the Source Code and Modify an Ubuntu Package

Tuesday, October 6th, 2015

Modifiying the Source of a Package and Creating a New Deb Binary

In order to download the source code of an existing package, first install the prerequisites:

sudo apt-get install build-essential debhelper

To get the source code of a package, run the following command:

apt-get source {name_of_package_interested_in}

Make changes to the source using an editor like geany or via terminal through nano.  Edit the changelog file and add a record of your changes to build a new revision number.  After you have made the changes, run the following commands to build the package which should include your changes.

dpkg-source --commit
dpkg-buildpackage -b

The updated package has been built.  To install the package, simply use the below commands:

sudo dpkg --install {name_of_new_deb_file}

To remove the software:

sudo dpkg -r {name_of_package [NOT NAME OF DEB FILE]}

Now you can release it!

Ubuntu Grub Fails to Install on RAID Array

Friday, February 6th, 2015

Ubuntu Grub RAID Issues

Grub Fails To Install on RAID Array

If grub fails to install on your RAID array in any version of Ubuntu, do NOT disable your BIOS RAID! The correct solution is at this blog entry. I'll summarize it below.

At the stage of the install where it is attempting to install GRUB it will detect as

/dev/mapper

This is incomplete! That's why the GRUB install fails.

You need the actual name of the RAID array to install to. So during that step, press ctrl+alt+F2 to drop to a busybox terminal, then enter

ls -l /dev/mapper

Pick out the name of your array from the list shown, then press ctrl+alt+F1 to switch back to the install (you can switch back and forth as much as you like with no problems) and enter it in the field as

/dev/mapper/{your array name}  

Then GRUB installs perfectly and you're ready to go, with a proper BIOS RAID array intact.

System Won't Boot After Grub Failed to Install

If your system will no longer boot because you skipped installing or updating grub, you need to download an Ubuntu version that does support RAID, boot from the LIVE CD, drop to a terminal, and then run:

ls -l /dev/mapper
sudo grub-install /dev/mapper/{ARRAY_NAME_HERE}

Setting Up RAID Array During Ubuntu Install

If you are configuring a BIOS RAID array for the first time on Ubuntu, you should create a 1MB boot partition.  Its partition type is "boot".  If you do this, grub will always try to install there and will succeed every time without failing when upgrading or reinstalling grub.

Install VSFTPD 3.0.2 on the ARM Platform for Raspbian or Debian

Saturday, January 3rd, 2015

Install VSFTPD 3.0.2 on the ARM Platform for Raspbian or Debian

Download and install the arm compiled VSFTPD 3.0.2 deb package file and init script:

wget -N http://dinofly.com/files/linux/vsftpd_3.0.2_arm.tar.gz
tar -zxvf vsftpd_3.0.2_arm.tar.gz
if [ ! -e "/etc/init.d/vsftpd" ]; then
    sudo cp vsftpd /etc/init.d/
fi
sudo dpkg -i vsftpd_3.0.2-1_armhf.deb

Now, run these commands:

sudo useradd -d /var/ftp ftp
sudo mkdir -p /var/ftp
sudo chown root.root /var/ftp

Finally, start the VSFTPD service and set it to run on boot:

sudo service vsftpd restart
sudo update-rc.d vsftpd defaults

VSFTPD 3.0.2 should now be installed on your ARM device.

Allow Anonymous Read Only FTP via VSFTPD

Saturday, January 3rd, 2015

Anonymous VSFTPD Setup (Read Only)

Configuration:

In order to enable anonymous FTP connections to a particular directory while still supporting authentication for virtual users for their files via PAM isn't that difficult.  Install VSFTPD if you haven't done so already by running the following command:

sudo apt-get install vsftpd

Create a backup of your existing VSFTPD confiugration file (this guide assumes you have already installed vsftpd):

sudo cp /etc/vsftpd.conf /etc/vsftpd.conf.bak

Next, let's edit the file:

sudo nano /etc/vsftpd.conf

Add the following lines to your configuration file:

anonymous_enable=YES
anon_root={INSERT_PATH_TO_ANONYMOUS_DIRECTORY}
anon_mkdir_write_enable=NO
anon_upload_enable=NO

Adding these lines enables anonymous FTP to the specified directory where files can be read and downloaded only.  Anonymous users cannot write, delete, change, or modify files because of the anon_mkdir_write_enable=NO and the anon_upload_enable=NO configuration lines.  For your changes to take effect, restart vsftpd.

sudo service vsftpd restart

You're done!

Geany PHP Beautifier

Saturday, August 16th, 2014

PHP Beautifier Support for Geany

Geany is by far one of the best text editors I have come across that works on both Windows and Linux.  It is also one of the most aesthetically pleasing editors to look at right out of the box.  I do a lot of PHP scripting, and as such, it is nice to have a "beautifier" script that will automatically format my code for me so that it looks nice.  Geany can also call the php executable and check your script syntax. You can achieve both of these features by installing both PHP for Windows and the PHP Beautifier PEAR addon.   

Install PHP for Windows:

If you code your PHP scripts in Windows, you'll want to use syntax checking and the PHP_Beautifier script.  To do so, you must install the PHP5 Windows package, which includes the main PHP binaries.

To get the files, download the latest version of PHP 5.3.

Extract the contents of the archive to "C:\php5"

Go into C:\php5 and rename "php.ini-development" to "php.ini".

PHP BEAUTIFIER WILL NOT WORK ON ANY NEW VERSION OF PHP FROM 5.4.X and UP!

Install PEAR for Windows:

PHP_Beautifier relies on PEAR functionality.  To install pear, save this file using a browser and place it in the "C:\php5" directory.  

Start command prompt, change directory into "C:\php5", and run the phar script:

C:\
cd C:\php5
php go-pear.phar

Install everything and keep default options.

Install PHP_Beautifier:

Now, install PHP Beautifier by running the following commands:

pear install PHP_Beautifier

Integration in Geany:

For PHP Syntax Checking:

In Geany, click on "Edit" in the menu bar and choose "Preferences".

In the "General" and "Startup" tabs, under the "Paths" section, paste "C:\php5" (without the quotes) into the "Extra plugin path:" field.

For PHP Beautifier:

Start the Geany text editor program.  Open a PHP script file.

Select the code you want to format, right click on the selected text, and choose "Format" –> "Send Selection to" –> "Set Custom Commands".

For command, use the following:

php C:\\php5\\php_beautifier -s4 -l "ArrayNested() NewLines(before=T_COMMENT:for:switch:foreach:T_CLASS:function:T_CLOSE_TAG,after=T_ENDIF:T_CLOSE_TAG:T_OPEN_TAG:T_ENDSWITCH:T_ENDWHILE:T_ENDFOR:T_ENDFOREACH)"

For "Label", use "PHP Beautifier"

Hit OK.

Now, select the code you want to format, right click on the selected text, and choose "Format" –> "Send Selection to" –> and pick "PHP Beautifier".  The code should now be formatted using the options specified in the command line arguments above.

For more filter options and commandline parameters, please read this PHP_Beautifier document.

 

Turn on IPv4 Easy Bash Way

Tuesday, January 21st, 2014

Turn on IPv4 Forwarding by running this script:

cd ~/Downloads
wget -N "http://dinofly.com/files/linux/ipv4_forward.tar.gz"
tar -zxvf ipv4_forward.tar.gz
sudo bash forwarding.sh

It should work on all versions of Linux but has been tested and works perfectly on Ubuntu.

Disable BIND9 Recursive DNS Queries to Prevent UDP DDOS Flood Attacks

Sunday, January 12th, 2014

Turn Off BIND9 Recursion

By default, BIND9 is configured to allow recursive DNS queries.  This allows others to use your DNS server to query other domains on your server's behalf.  Unfortunately, recursive DNS queries can be used to amplify a UDP flood DDOS attack.  As such, for a shared web hosting environment, it is best to disable recursive DNS queries.  You can disable BIND9 recursion easily by running the following script:

cd ~/Downloads
wget -N "http://dinofly.com/files/linux/disable_bind9_recursion.tar.gz"
tar -zxvf disable_bind9_recursion.tar.gz
sudo bash disable_bind9_recursion.sh

It should work on all versions of Linux but has been tested and works perfectly on Ubuntu.  You may need to change the path used for the BIND config file. 

MySQL Dump Insert Statements Only

Saturday, September 14th, 2013

Using mysqldump to Create SQL Backups with Only Insert Statements and Ignore Existing Records

mysqldump -u USER -p PASSWORD --skip-triggers --compact --no-create-info --insert-ignore DBNAME