Linux Guides & Reviews
RSS icon Home icon
  • Nmap – List of Hosts Responding to Ping

    Posted on May 19th, 2013 admin No comments

    I was trying to figure out how to return a list of ips on my network that are responding to ping. Here’s how you do it with grep, and get a list of just ips:

    sudo nmap -sP | grep -o 192.[0-9]*.[0-9]*.[0-9]*

    Modify “″ for your network’s ip range.

  • Mythtv – 0.26 Bug Fixes

    Posted on February 2nd, 2013 admin 2 comments

    I just upgraded to Mythtv 0.26, and I’ve had some issues with it, so I decided to keep a log of what I had to change. This is mostly for me to reference in the future.

    MythTranscode Error

    I normally use mythtranscode to remove commercials from my recordings after setting the cutpoints. Unfortunately, after my upgrade, mythtranscode started crashing on every attempt with the following error:

    CoreContext mpeg2fix.cpp:698 (AddFrame) Deadlock detected. One buffer is full when the other is empty! Aborting

    This post recommended that I copy the mythtranscode binary from 0.25, and use that, which worked after copying all of the necessary libraries.

    Mythweb Default Aspect Ratio

    Mythtv loses the aspect ratio data that is stored in the database (but not the data stored in the actual video used for playback) when a video is transcoded. I transcode some recordings to remove commercials, so videos show up incorrectly in mythweb after being transcoded, and default to an aspect ratio of 4/3. Since most of my recordings are 16/9, I modified the default aspect ratio to be 16/9 by modifying “modules/tv/classes/Program.php” (line 826) to be:

    return 16/9

    More will be added later.

  • Monitoring SSD Life

    Posted on September 1st, 2012 admin No comments

    Smartmon can be used to monitor the wear and tear on a SSD. The Media_Wearout_Indicator monitors the life of the drive, and counts down from 100 to 0, 100 meaning 100% of the drive life is left, and 0 meaning 0% of the life of the drive is left. Use the following command to view the life of the drive left:

    sudo smartctl -a /dev/sdc | grep Media_Wearout_Indicator

    The size of partitions on the SSD also does not matter (eg: if the root directory is almost full, and the home directory is relatively empty). See the following article about Block Shuffling and Over-Provisioning. Blocks are shuffled between partitions to level wear on the drive.

    More useful information about Media_Wearout_Indicator

  • Yate Server: Free Google Voice Calling

    Posted on June 1st, 2011 admin 27 comments

    This post details how to setup yate as a google voice sip server. Please feel free to post any questions you have in the comments section.


    Use one of the respositories, or install from source. Download links are available here.

    Figure out where all of the configuration files are located. They should either be in /etc/yate, or /usr/local/etc/yate, depending on what you installed from. The rest of these instructions will describe the necessary modifications to each specified file.


    This file sets the username and password you will use to login using your sip software client, or ATA. Add the following to the end of the file, replacing ‘mysipusername’ with the username you want to use, and ‘mysippassword’ with the password you want to use:



    This file contains your gtalk username and password. Add the following to the end of the file, replacing ‘mygvusername’ with your password, and ‘mygvpassword’ with your password.



    You need to enable a module for gtalk to work properly.  Add the following to the end of the postload file (so that part of the file should look like the following:

    ; Put a line in this section for each shared library that you want to load
    ;  after all Yate modules
    ; Each line has to be of the form:
    ;   /path/to/the/library.so=boolean
    ; You should specify the full path to the library. Extension is operating
    ;  system specific - usually .so for *NIX systems and .dll for Windows


    You need to change the jingle channel so it runs in client mode instead of server mode. Remove the ‘;’ from the beginning of the:


    line, and change it to:


    also uncomment the following two lines and change them to:



    This file describes how incoming and outgoing calls are handled. We need to route incoming calls (from gtalk / google voice) to our sip phone. Add the following to the end of the ‘[contexts]’ section to route incoming calls, replacing ‘mysipusername’ with the sipusername you set above in the regfile.conf file:


    Next add the following to the ‘[default]’ section to route outgoing calls through google voice. The first line needs to be right below the ‘[default]’ section header. This blocks unauthenticated users from making calls:

    ^\([1-9][0-9][0-9][0-9][0-9][0-9][0-9]\)$=jingle/513\[email protected];line=GoogleVoice;ojingle_version=0;ojingle_flags=noping;redirectcount=5;checkcalled=false;dtmfmethod=rfc2833
    ^\([1-9][0-9][0-9][1-9][0-9][0-9][0-9][0-9][0-9][0-9]\)$=jingle/1\[email protected];line=GoogleVoice;ojingle_version=0;ojingle_flags=noping;redirectcount=5;checkcalled=false;dtmfmethod=rfc2833
    ^\(1[1-9][0-9][0-9][1-9][0-9][0-9][0-9][0-9][0-9][0-9]\)$=jingle/\[email protected];line=GoogleVoice;ojingle_version=0;ojingle_flags=noping;redirectcount=5;checkcalled=false;dtmfmethod=rfc2833
    ^\(+1[1-9][0-9][0-9][1-9][0-9][0-9][0-9][0-9][0-9][0-9]\)$=jingle/\[email protected];line=GoogleVoice;ojingle_version=0;ojingle_flags=noping;redirectcount=5;checkcalled=false;dtmfmethod=rfc2833


    I attempted to install from this repository, but yate gave me some error about jabberclient.yate (from /usr/lib/yate/…), so I installed from source.

    edit: I fixed this by compiling, and then copying ~/yate/modules/client/jabberclient.yate to /usr/lib/yate/client/

    All installation options are shown here.


    A developer on the Yate mailing list helped me out, and made a script that automatically presses 1 on incoming calls to accept the call.  Here’s how to enable it:





    This script is not included in the newest version of yate (it’s in the trunk version). If you installed from the repositories, install ‘yate-scripts’, and then download the following file: http://voip.null.ro/svn/yate/trunk/share/scripts/postanm_dtmf.php, and save it to ‘/usr/share/yate/scripts’ (or wherever the scripts are located for your system).

    Current Issues:

    I am having some issues getting call working in the newest version of yate (4.0.0 1). Here’s my tracking of the issue, and possible solutions:

    1. Outgoing calls silent ~30% of the time:
      Tried setting “timeout=0″ in yrtpchan.conf, which appears to at least temporarily be working.
    2. Incoming calls not working.
    3. First few seconds of outgoing call audio missed.
  • Install Chromium in Ubuntu 10.04 (Lucid)

    Posted on May 19th, 2010 admin 3 comments

    Chromium is the open source version of google chrome.

    Installing Chromium in Ubuntu 10.04 is a very simple and quick process.  Just run the following three commands in your terminal (Applications/Accessories/Terminal):

    sudo add-apt-repository ppa:chromium-daily/ppa
    sudo apt-get update
    sudo apt-get install chromium-browser

    Integrating Chromium into new ubuntu theme:

  • Pithos Segmentation Fault Fix

    Posted on May 5th, 2010 admin 2 comments

    Pithos crashes with a segmentation fault in Ubuntu 64-bit.

    The build queue is apparently backed up right now, so it may take some time before the patched version is released.  To manually fix your installed version, do the following:

    1. gksudo gedit /usr/bin/pithos
    2. Comment out line 173 (by placing a # character).
    3. Save and close the file.

    Thanks to Kevin for this fix!

  • Ubuntu: Why the Buttons Were Moved in 10.04

    Posted on May 5th, 2010 admin 3 comments

    When Canonical decided to move the close, minimize, and maximize buttons in 10.04 to the left side of the window, Mark Shuttleworth simply said that something very exciting was going to go on the right side.

    Now we know what that is.  Window Indicators, or “Windicators” are going to go in their place.

    This area will be used similar to the indicators near the clock in ubuntu.  Small buttons will provide volume control per application (using features that pulseaudio already provides), online/offline status, and status messages (such as saving, etc).  This will allow the status bar of many applications to be moved to be removed, and those buttons placed at the top of the window.


    I have mixed feelings on this.  One part of me celebrates a change like this, with Ubuntu blazing their own path, but another part of me absolutely hates this change.  Most people are intuitively used to clicking in the top right corner to open/maximize/close a window.  Now this fundamental design choice has been changed, which will take some getting used to.

    Also, as far as I can tell, this is going to require developers to modify their programs to support this (hopefully I am wrong though).  If Ubuntu is the only distro that does this, how many developers will do this.  What about KDE?

    Mark goes into a lot more detail on his blog:


  • Move Window Buttons to Right Side – Ubuntu 10.04

    Posted on May 5th, 2010 admin 7 comments

    The developers at Canonical decided to move the position of the minimize, maximize, and close buttons in Ubuntu 10.04. For most people like myself this is an unwelcome change. We are used to clicking in the top right to minimize/close windows.

    Fortunately changing this back requires running only one line of code:

    Open up terminal, or the run application box (Alt-F2), paste the following command in, and run it:

    gconftool-2 --set /apps/metacity/general/button_layout --type string menu:minimize,maximize,close

    These changes should be instantaneous.

    Moving Back to the Left Side:

    If you ever want to change this back, all you have to do is run:

    gconftool-2 --set /apps/metacity/general/button_layout --type string close,minimize,maximize:

    If you are wondering why this has been changed, see this post:

  • Playing Flash Videos in External Player

    Posted on November 11th, 2009 admin 3 comments

    I have had a lot of issues with flash videos in the past. I have had some difficulties with it crashing in firefox, and I have had issues with full screen support. There are services that let you download and then play the flash video in an external player, but normally I just want to immediately watch it, but be able to watch it in an external player.

    There is an easy solution to this. Just load the video in firefox, and then hit pause once it starts playing. Then, open up the terminal, and run the following command:

    smplayer /tmp/Flash*


    vlc /tmp/Flash*

    This probably also works for many other video players using similar commands.  I have had success with youtube, and vimeo when using this, but I would assume that it also works with many other video services.  This will not work with encrypted flash videos though.

  • Copy SSH Key to Server in One Line

    Posted on September 26th, 2009 admin No comments

    Here is a simple way to copy your public key from your computer to your server (which can allow password-free login):

    ssh [email protected] "echo `cat ~/.ssh/id_rsa.pub` >> ~/.ssh/authorized_keys"

    If you receive an error about ~/.ssh/id_rsa.pub not existing, run the following to create it first:

    ssh-keygen -t rsa