Category Archives: OS

Install Virtualbox on a Chromebook

I am really enjoying my Chromebook Pixel 2015. Recently I needed to spin up a few VMs on this box. I tried to install virtualbox but it turns out that the kernel for the chromebook does not include virtualbox headers. Fortunately it’s fairly easy to add them, thanks to divx118’s scripts.

First, enable the necessary chromebook kernel flags. Run these commands in a crosh shell (not in a chroot)

cd ~/Downloads
wget https://raw.githubusercontent.com/divx118/crouton-packages/master/change-kernel-flags
sudo sh ~/Downloads/change-kernel-flags

Note: You will need to repeat the above steps after each chromeos update.

Next, open up a chroot shell and do the following:

cd ~
wget https://raw.githubusercontent.com/divx118/crouton-packages/master/setup-headers.sh
sudo sh setup-headers.sh

Lastly, reboot the chromebook. Once you’re back up, enter your chrooted environment and install Virtualbox from their Oracle’s download page. Don’t use the virtualbox repositories – they don’t work.

Install the downloaded deb file with dpkg

dpkg -i virtualbox-5.0_5.0.10-104061~Ubuntu~trusty_amd64.deb

You might get this error:

dpkg: dependency problems prevent configuration of virtualbox-5.0:
 virtualbox-5.0 depends on libqt4-opengl (>= 4:4.7.2); however:
  Package libqt4-opengl is not installed.

The fix to that error is to run the following command to install missing dependencies:

apt-get -f install

If you get weird errors about VT-X not being enabled in the BIOS, try running the script and rebooting again.

Success!

Install Owncloud 8 on Centos 7

I recently needed to re-install my Owncloud VM. I’ve been on a CentOS kick lately so I decided to see if I could install OwnCloud 8 on a Centos 7 base install. It turned out to not be as easy as I thought it would be.

When I tried to install owncloud on my CentOS 7 system, I kept getting a 404 error message even though I followed the documentation outlined here.

It turns out that they changed where the RPM is held and apparently forgot to update the documentation. I discovered this by manually navigating to download.suse.org/repositories/isv:ownCloud:community and browsing the directories. The documentation has you grab a repo from Centos_Centos-7 folder, which is broken. It looks like the proper directory is just Centos_7.

I had to remove the old repo, purge the cache, and try again. To do so, remove the .repo file and purge via yum:

cd /etc/yum.repos/d/
rm isv\:ownCloud\:community.repo
yum --enablerepo=isv_ownCloud_community clean metadata
wget http://download.opensuse.org/repositories/isv:ownCloud:community/CentOS_7/isv:ownCloud:community.repo
yum install owncloud

The above procedure is what you should run if you’ve already tried to use the broken link in the documentation and failed. If you haven’t installed owncloud yet, do the following

cd /etc/yum.repos/d/
wget http://download.opensuse.org/repositories/isv:ownCloud:community/CentOS_7/isv:ownCloud:community.repo
yum install owncloud

Success.

Fix raidcheck error on Xenserver 6.5

After configuring a software RAID to host my VMs on my Xenserver 6.5 instance I began receiving odd e-mails once a week. The e-mails simply said:

/usr/sbin/raid-check: line 62: declare: -A: invalid option 
declare: usage: declare [-afFirtx] [-p] [name[=value] ...]

It turns out /usr/sbin-raid-check is a bash script called from the file /etc/cron.d/raid-check. It’s a weekly cron job designed to “scrub” the RAID array. I was getting these e-mails because I had configured my xen server to e-mail me anything sent to root, which includes messages encountered during cron jobs.

There appears to be a typo in the raid-check script. Line 62 of raid-check reads:

declare -A check

After reading the syntax of the declare command, I believe the issue is the fact that the A is capitalized. I commented out that line and replaced it with

declare -a check

That seemed to work. No more weird errors coming from my xenserver.

Install Splunk Universal Forwarder on Linux

I do this infrequently enough that I decided I should really write this down. Below is the quick and dirty way to get the Splunk universal forwarder installed on a new Linux  system. Thanks to byteschef for the information used to create this guide.

Download the latest splunk .RPM from their site and install it via RPM -i <filename> (if RedHat based) or dpki -i <filename> if debian based.

Run the following commands as root:

cd /opt/splunkforwarder/bin
./splunk start --accept-license
./splunk enable boot-start
./splunk add forward-server <IP/hostname of splunk server>:9997 -auth admin:changeme
./splunk add monitor /var/log
./splunk edit user admin -password NEW_PASSWORD -auth admin:changeme
./splunk restart

If there are any other directories you want monitored other than /var/log (application logs, for example) then issue:

./splunk add monitor <directory to monitor>

Done.

Fix Owncloud 8.1.1 samba shares not working

It never seems to go smoothly, does it? I just upgraded my version of Owncloud from 8.0.4 to 8.1.1 on my Ubuntu Trusty Tahr 14.04 VM. After the upgrade I noticed that all my samba (SMB) shares were gone. The logs were not very helpful, full of things like these:

Exception: {"Exception":"Icewind\\SMB\\Exception\\InvalidHostException","Message":"","Code":0,"Trace":"#0 \/var\/www\/owncloud\/apps\/files_external\/3rdparty\/icewind\/smb\/src\/Connection.php(37): Icewind\\SMB\\Connection

Additionally errors like this were showing up:

Your web server is not yet set up properly to allow file synchronization because the WebDAV interface seems to be broken.

After much digging I discovered this post which had a suggestion to install libsmbclient-php. In Ubuntu 14.04 it involves this command:

sudo apt-get install php5-libsmbclient

That did the trick! After installing php5-libsmbclient my samba shares worked once more.

 

Avoid prompts when installing FreeBSD ports

The FreeBSD ports tree is wonderful for installing software but sometimes it can be a real pain. Recently I was trying to install Emby in FreeBSD because why not? The instructions were easy enough except for when I ran

make install clean

I was constantly barraged with choices for things. I want to assume the default on all of these and not be barraged with questions.

Thanks to stack exchange I learned it’s relatively easy to bypass all these questions. Simply add:

BATCH=yes

to the end of your make install clean statement to assume the defaults to all the questions for the package. The Emby guide is pretty comprehensive, but I would add this command at the bottom:

make install clean BATCH=yes

Handy.

Disable IPv6 on an interface in Linux

After tethering my phone to my laptop and googling “what is my ip” I was surprised to find an IPv6 address. Apparently my mobile carrier has implemented IPv6. Bravo to them.

Unfortunately, when I initiated my VPN, which is supposed to tunnel all traffic through it, my IP address didn’t change. This is because my VPN is IPv4 only. My system prioritizes IPv6 traffic, so if I happen to go to any IPv6 enabled site such as google, my VPN tunnel is bypassed entirely.

I don’t like the security implications of this. The long term solution is to implement IPv6 with my VPN; however while traveling I won’t be able to do that. The short term solution is to simply disable IPv6 for the interface that has it, in my case usb0 as that is what is tethered to my phone.

This simple command will do the trick:

sudo sh -c 'echo 1 > /proc/sys/net/ipv6/conf/usb0/disable_ipv6'

Change USB0 to whatever interface you would like (or all of them) and you’re done! Thanks to this site for the information.

 

 

 

Install Cinnamon on a Chromebook with Crouton

I really love using Crouton on my Chromebook Pixel LS 2015. I was sad to see that there is no cinnamon desktop environment target with the latest versions of crouton. Below is what I did to get Cinnamon on my chromebook. Much of what I did was taken from https://gist.github.com/sohjsolwin/5939948

  1. Create a base chroot
  2. Enter your chroot
sudo apt-get update
sudo apt-get install software-properties-common python-software-properties
sudo add-apt-repository ppa:tsvetko.tsvetkov/cinnamon
sudo apt-get update
sudo apt-get install cinnamon

Once Cinnamon was installed I needed to know how to start it manually. Thanks to the Arch Linux forums for explaining it. You have to create a .xinitrc file in your home directory within your chroot.

echo "exec cinnamon-session" > ~/.xinitrc

Trying to manually start cinnamon by typing startx didn’t work – I got a blank screen and had to hard reset to get anything to come back. Thanks to github I learned you need to use xinit instead of startx.

Lastly, we need to create a suitable startcinnamon script.

wget https://gist.github.com/sohjsolwin/5934362/raw/f68fc0942798902a0bd48f40c17dc0cd5cf585ea/startcinnamon

Modify the file to remove the startx command with xinit. Also remove everything after xinit. My file is as follows:

APPLICATION="${0##*/}"

USAGE="$APPLICATION [options]

Wraps enter-chroot to start a Mint session.
By default, it will log into the primary user on the first chroot found.

Options are directly passed to enter-chroot; run enter-chroot to list them."

exec sh -e "`dirname "$0"`/enter-chroot" "$@" xinit

Make this file executable (chmod +x startcinnamon) and move it to the /usr/local/bin directory of your chromebook (not your chroot.) Now all you need to do is enter

sudo startcinnamon

and your cinnamon desktop should come up!


 

Update 2016-01-04

These two scripts seem to work a little bit better. Place this one within your chroot under /usr/local/bin/startcinnamon:

#!/bin/sh -e
# Copyright (c) 2015 The crouton Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# Launches GNOME; automatically falls back to gnome-panel

exec crouton-noroot gnome-session-wrapper cinnamon

Place this one in /usr/local/bin outside your chroot (on your chromebook itself.)

#!/bin/sh -e
# Copyright (c) 2015 The crouton Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

set -e

APPLICATION="${0##*/}"

USAGE="$APPLICATION [options]

Wraps enter-chroot to start a GNOME session.
By default, it will log into the primary user on the first chroot found.

Options are directly passed to enter-chroot; run enter-chroot to list them."

exec sh -e "`dirname "\`readlink -f "$0"\`"`/enter-chroot" -t cinnamon "$@" "" \
    exec startcinnamon

Install Ubuntu chroot on your Chromebook

I recently got a Chromebook Pixel 2015 LS. It is a very nice device. Chromium OS is great but a power user like myself wants a little more functionality out of this beautiful machine.

Fortunately it’s not too difficult to get an Ubuntu chroot running side by side with chromium. The Google developers have made a script to automate the process.

Below is my experience installing an Ubuntu Trusty chroot on my chromebook 2015 LS.

Prepwork

  • Enter developer mode:
    Press ESC, Refresh, power simultaneously (when the chromebook is on)

    • Every time you power on the chromebook from now on you’ll get a scary screen. Press CTRL-D to bypass it (or wait 30 seconds)
    • If you hit space on this screen instead of CTRL+D it will powerwash (nuke) your data
      A scary screen will pop up saying the OS is missing or damaged. Press CTRL D, then press Enter when the OS verification screen comes up.
  • Wait several minutes for developer mode to be installed. Note it will wipe your device to do this.

Install Crouton

Now that we’re in developer mode we will use a script called crouton to install an Ubuntu chroot (thanks to lifehacker for the guidance.)

  1. Download Crouton:  https://github.com/dnschneid/crouton
  2. Press CTRL ALT T to open terminal
  3. Type ‘shell’ (without quotes) and hit enter
  4. sudo sh ~/Downloads/crouton -r trusty -t touch,extension,unity-desktop,keyboard,cli-extra -e -n unity
    1. Note the arguments are suited to my needs. You will want to read up on the documentation to decide which options you want, i.e. desktop environment
  5. Install this crouton extension to integrate clipboard (in conjuction with the ‘extension’ parameter above)

General points of interest / lessons learned

  • Don’t enter the chroot and type startx. It will hard freeze your chromebook.
  • You don’t need to blow your chroot away if you want a different desktop environment, simply install desired environment on your existing chroot
  • To switch between chroots pres Ctrl + Alt + Shift + F2 or F3 (back or forward arrows on top row, not to be confused with the arrows on the bottom right of the keyboard)

High DPI

High DPI screens are a pain to deal with. Here are my tweaks:

  • Go to System settings / Displays / Scale for menu and title bars. I like 1.75
  • Alternatively you can change your resolution. If you mess up and X won’t start properly, delete ~/.config/monitors.xml (thanks to askubuntu)
  • Use the setres script to enable other resolutions in the display manager
    • setres 1440 960
  • Firefox fix tiny text:
    • go to about:config and modify layout.css.devPixelsPerPx, set to 2

Other tweaks:

  • Make trackpad match Chrome:
    • System settings / mouse and trackpad / Check “Natural Scrolling”
  • Remove lens suggestions:
    • Install unity-tweak-tool, notify-osd, overlay-scrollbar, unity-webapps-service
    • Run unity-tweak-tool and uncheck “search online sources” from the search tab
  • Move docky bar to the left:
    • sudo apt-get install gconf-editor
    • Press Alt+F2, enter: gconf-editor and in this configuration editor, navigate to “apps -> docky-2 -> Docky -> Interface -> DockPreferences -> Dock1″
    • On the right side there are some properties with their corresponding values, including the position of the dock which you can change from “Bottom” to “Top/Left/Right” to move Docky to the upper part of the desktop.
  • Install Mac OSX theme
  • Install elementary OS chroot

Garbled mouse cursor when switching between chroots

Sometimes the mouse cursor would get all weird when switching between my chroots. The fix is to install the latest Intel drivers within your chroot.

sudo apt-get install software-properties-common python-software-properties
sudo add-apt-repository https://download.01.org/gfx/ubuntu/14.04/main
wget --no-check-certificate https://download.01.org/gfx/RPM-GPG-KEY-ilg -O - | sudo apt-key add -
wget --no-check-certificate https://download.01.org/gfx/RPM-GPG-KEY-ilg-2 -O - | sudo apt-key add -
sudo apt-get update
sudo apt-get upgrade

That’s it.. for now 🙂


 

Update 07/27/2015

I discovered that creating chroots was taking a very long time due to the mirror being chosen. I discovered the -m parameter of crouton which allows you to specify a mirror of your choosing. My updated setting is thus:

sudo sh ~/Downloads/crouton -r trusty -t touch,extension,kde-desktop,keyboard,cli-extra -e -n unitykde -m http://mirrors.xmission.com/ubuntu

If you happened to do a CTRL + C to cancel an existing chroot install that was going slowly, you can simply append the -m parameter above along with -u -u to resume with the updated mirror:

sudo sh ~/Downloads/crouton -r trusty -t touch,extension,kde-desktop,keyboard,cli-extra -e -n unitykde -m http://mirrors.xmission.com/ubuntu -u -u

Install OTRW2 on DD-WRT

Optware done the right way 2 is a set of scripts designed to enhance the functionality of your DD-WRT router. I’ve recently installed it on my parents’ router so I can more or less have a full Linux box running in their house (it makes my life easier.)

The tutorial for install it is pretty comprehensive. These are my notes on the experience.

  • USB devices needs to be ext2 formatted (fat won’t do.) This is because the script makes a bunch of symlinks to that device.
  • Mount ext2 formatted drive as /opt (Services / USB / Disk Mount Point)
  • Reboot router if you made any changes to mountpoints.

SSH into the router and run the following:

wget -O /tmp/prep_optware http://dd-ware.googlecode.com/svn/otrw2/prep_optware
sh /tmp/prep_optware

Installation takes some time. Wait one minute after installation complete message and reboot router.

Once rebooted, use the service command to see which services are available. Green means the service is enabled.

service mypage on

Enables the mypage service, but you still have to reboot. Reboot router after any changes to services to enable / disable them.

Small overview of services as taken from dd-wrt forums:

rotate_log = move the log file to /opt/var/log/
pixelserv = addblocking on you network.
unfsd = nfs server
zabbix = zabbix client (useless since its included in kong build)
pound = reverse proxy which you can use since you host multiple sites
sshhack = block ips hammering ssh with incorrect credentials.
stophack = BLock ips which are trying to hack server (only combined with pound or vlighttpd)
stophammer = block ips which are hammering ports
nzbget & transmission for downloading.
fixtables rearranges the firewall entries

A full explanation on how otrw2 enhances your router and what each package does is located here.

All in all, pretty straightforward once you get the right filesystem on your media and have it mounted on the right mountpoint. OTRW2 gives your router a whole lot more usefulness and the ability to install a wide range of packages on it.