Archive for the ‘Ubuntu Linux’ Category

Installing the Newest Version of Python 2.7.x on Older Versions of Ubuntu (like 14.04)

Thursday, May 9th, 2019

Installing the Newest Version of Python 2.7.x on Older Ubuntu Systems

If you need to upgrade to the newest version of Python 2.7.x, and you're running an older distribution (like Ubuntu 14.04), use the following commands to get the latest version (works on Ubuntu 17.04 and older – tested on Ubuntu 14.04):

sudo add-apt-repository ppa:jonathonf/python-2.7
sudo apt-get update
sudo apt-get install python2.7

Then, you'll need to cleanup a few leftover system packages manually before installing the newest version of python-pip.  If you don't do this, you'll run into problems installing some new packages using pip.

sudo rm /usr/lib/python2.7/dist-packages/chardet*.egg-info
sudo rm -r /usr/lib/python2.7/dist-packages/chardet
sudo rm /usr/lib/python2.7/lib-dynload/_hashlib.x86_64-linux-gnu.so
sudo rm /usr/lib/python2.7/lib-dynload/_hashlib.i386-linux-gnu.so

Now, you can download and install the newest version of python-pip:

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
sudo python get-pip.py

Getting Let's Encrypt Certbot to Work:

First, you'll need to install a few packages that Certbot (the Let's Encrypt client) uses:

sudo pip install requests
sudo pip install hmac

Now, you'll need to delete the EFF directory from the /opt directory to avoid old configuration issues that were used for your older version of python.  Once you cleanup this directory, you'll run certbot again so it can reconfigure itself. 

sudo rm -r /opt/eff.org/
sudo certbot

You're done.

Full list of commands (for quickly doing all of the above):

sudo -i
add-apt-repository ppa:jonathonf/python-2.7
apt-get update
apt-get install python2.7
rm /usr/lib/python2.7/dist-packages/chardet*.egg-info
rm -r /usr/lib/python2.7/dist-packages/chardet
rm /usr/lib/python2.7/lib-dynload/_hashlib.x86_64-linux-gnu.so
rm /usr/lib/python2.7/lib-dynload/_hashlib.i386-linux-gnu.so
mkdir -p /root/Downloads
cd /root/Downloads
curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
python get-pip.py
pip install requests
pip install hmac
rm -r /opt/eff.org/
certbot

Change the Default Editor to nano in Linux

Saturday, April 27th, 2019

Use nano as the Default Editor

If you hate vi like I do, you can configure Linux to always default to using the nano editor.

Simply add the following to the bottom of the /etc/bashrc file:

export EDITOR="nano"

Save the file.  nano is now the default editor.  When you use

sudo crontab -e

The nano editor will now be used by default.

Copying LVM Containers from One Remote Server to Another

Saturday, April 27th, 2019

Transferring LVM Containers

Before you transfer a KVM container to another machine, create a KVM virtual machine on the target server with the same or larger disk size than the container being transferred. 

You can see a full list of LVM containers by using the below command:

sudo lvdisplay

Copying an LVM Container from the Local Machine to a Remote Server

sudo -i
dd if=/dev/vms/phpdev bs=4096 | pv | ssh root@IPADDRESS_HERE -p SSH_PORT 'dd of=/dev/pool/phpdev bs=4096'

Adjust the above pool paths as necessary since this may vary from server to server. 

Copying an LVM Container from a Remote Machine to the Local Machine

sudo -i
ssh root@IPADDRESS_HERE -p SSH_PORT "dd if=/dev/vms/phpdev bs=4096" | dd of="/dev/vms/phpdev" bs="4096"

Adjust the above pool paths as necessary since this may vary from server to server. 

Running PolicyKit (pkexec) Commands without Prompting for Authentication

Saturday, December 8th, 2018

PolicyKit pkexec – Running without Prompting for Authentication

The following guide explains how to configure a pkexec command to run without prompting for authentication.  This is helpful when you want to grant root access to key piece of the system (such as allowing virsh commands from another user when running KVM virtual machines) or just want to run a GUI command as root without having to login or use authentication. 

https://askubuntu.com/questions/383747/how-to-configure-pkexec-to-not-ask-for-password#answer-388660

Or in our own archive in case the above link disappears.

Full Ubuntu Startup Applications Location List

Saturday, December 8th, 2018

Location of Ubuntu Startup Application Scripts

All Versions of Ubuntu

In all versions of Ubuntu, startup scripts can be configured and run from the following locations:

/etc/init/*.conf – some init scripts
/etc/rc.local – a file that is run by root on system boot (bash scritps and other commands can go in here)
~/.config/autostart – user specific GUI programs that are run once the X11 environment is started
/etc/xdg/autostart – Global GUI programs that are run once the X11 environment is started
@reboot cronjob – cronjob scripts that are executed when the system boots

Ubuntu 16.04 and Later

systemd init scripts in /etc/systemd/system/*.service files
systemd init scripts in /lib/systemd/system/*.service files

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.