So if you haven’t heard of Jolicloud http://www.jolicloud.com/, then you need to download and install it now. It’s an Ubuntu based OS (a self-proclaimed “Cloud OS”) specifically designed for Netbooks, and it rocks. I have Jolicloud installed on my Samsung N110 Netbook, and I use it for everything from e-mail to games (snes9x) to work (Perl/Vim/Screen). Now what makes Jolicloud super-awesome is that it treats web applications no differently from desktop applications. Each application gets it’s own icon on the “Home screen”. It’s also socially aware - it can connect to facebook and allow you to search for applications and/or people who’ve used those applications, so that you can ask them questions and get guidance on the tools you’re trying to use.

The interface is very slick - big icons and a clean method of navigation to the lesser used functions of a standard Gnome/Ubuntu desktop. The most-awesomest part is that once you load up a terminal, you have full access to the command-line and all Ubuntu apt repositories.

Jolicloud isn’t just for netbooks! I’ve also installed it on my Acer Veriton (similar to the Acer Revo), and am using it as a media center OS. Jolicloud also comes in an “express” edition, which allows you to install it under windows, where it will come up as a secondary OS option under the windows boot-loader.

If you have a netbook, nettop, or any light-weight PC, then install Jolicloud. Highly recommended.

The Problem

The time had come for me to “invest” in getting some new equipment. The only workstation that I had up until recently was a company laptop which I had toted back and forth between VMware and my home office. I keep my personal documents on removable storage, but that doesn’t really help when you don’t have a workstation at home, so lugging the laptop around with me was a must.

Don’t get me wrong, I have systems, but their mostly systems running as file servers or VM servers doing various little things automagically, and they’re not sitting in or around my actual desk at home. Also, my printers/scanner at home relied on my laptop to be of any use. It was time to fix all of these unecessary grievences.

The Dilemma

For the past couple of weeks I had been thinking hard about what kind of system I should buy - should it be a powerful / modern desktop system with lots of RAM and screaming CPU/Video? Or would it be a powerful laptop/notebook which would serve as a desktop replacement? Should I go for the i3, i5, or i7 processor? ATI or Nvidia? What kind of budget was I looking at?

All of these questions plagued me for quite some time (okay, not that long.. I admit I’m a bit of an impulse buyer). I’ve spent long enough thinking about this that I realized a lot about myself. For one, I’m not a gamer. I was once one of those people who would have been ecstatic about getting next-gen hardware to play the lastest power-hungry games. Not any more.. and not for quite some time. The last time I seriously played a PC game was about 3 years ago. When I say “seriously”, I mean played it regulary, at least once a week. The last game I played was a game that I was really into; it was X2 of the X-Series space combat simulators.

Since then, I’ve touched a game or two, on and off, but the has fascination is no longer there. i’m more interested in hacking around with open source programs and becoming a better developer.

The Solution

Since I wasn’t going to focus on gaming and media for my new system purchase, this opened the door for a lot of possibilities that I haven’t considered, and some unexpected disappointments. First off, since I wasn’t going to plop $1,000.00 on a single system, I could, theoretically buy two lower-powered systems. And that’s exactly what I did. Instead of going with a full-fledged desktop or power-house laptop, I ended up buying an Acer Aspire Revo net-top unit as my primary workstation, and a Samsung N110 Netbook as my portable. This Revo is awesome! It has 2GB of RAM (upgradable to 4), an Nvidia ION chipset, and an Intel Atom processor (dual-core). I didn’t need much more than this for my purposes, this was perfect. The Samsung N110 was also a nice little beauty. It was a Atom processor with integrated graphics, but was light, pretty, and had a 6-cell battery, which meant that it would last about 8 hours during heavy use. I quickly installed JoliCloud Express on the Netbook, and have been very happy with it ever since.

The Disappointment (In myself)

The disappointment that I experienced was not in the purchase or the hardware, but it was in the fact that I hesitated for a long time to wipe away the Revo’s bundled OS to install Linux. The OS that the Revo came with was Windows 7 Home edition (the Samsung netbook had Windows XP). I haven’t used windows as my primary OS in years, and have always been proud to say so. For the last four years or so, I’ve been using Ubuntu (severely customized), and before that I was using Debian. When I initially started up the Revo, I was impressed by the windows 7 user interface, the nice colors, the clean lines, and the fact that it picked up all my hardware. It was pretty simple, and I have to admit somewhat luring. I’m definately not the little hacker I was 10 years ago. I don’t have time to spend hours hacking away into the wee morning just on my OS configuration. At least that’s what I keep telling myself :) But then it dawned on me - that’s how I got where I am today, by embracing curiousity, and defying conformity. That’s where life becomes interesting and liberating, and that’s where I feel at home. All these thoughts of nostalgia hit me shortly after I hard-reset the Revo, and windows 7 came up saying “system wasn’t shut down correctly - use safe mode” or something to that effect. There was no way for me to tell it to disregard the unclean boot-up, it persisted to ask me to go into safe mode, with no specific explanation. That’s when I wish I had a grub prompt or command line handy.

Diving in with Arch Linux

After coming to my senses, I realized that I definately didn’t want to go back to using Ubuntu for my primary workstation. For a while I’ve been feeling like Ubuntu has lost much of it’s luster, especially for someone like me who loves simplicity and minimalism over fancy GUIs and extra features. I wanted a distribution that tried to stay at the cutting edge with it’s packages, but didn’t screw with the basics of linux so much that you’re forced to use GUIs to configure your OS. Debian didn’t fit the bill here - it’s great for servers - rock solid, but it’s not that great if you want a cutting edge workstation without having to compile things from source.

After a little bit of reading and browsing distrowatch.com, I came across Arch Linux (which I’ve known of only in passing before), and decided that this was the OS for me. The Arch Linux community is small enough that I could make some significant contributions without much effort. The distribution itself is awesome, very clean, and very minimal. And most importantly, all of the system configurations are done by editing text files!

The Arch Way

Installing Arch was relatively straight-forward (IMO). It wasn’t as easy as installing, say, Linux Mint, but it also wasn’t as hard as installing Debian 3.0 either. The installation dialogs were ncurses based, but they were descriptive, linear, and logical. When it came time to supply arguments for the initial configuration of the packages I selected, they were all text files (very well documented) which I could edit with vim! I think at that point I knew that was about to embrace a distribution that was very special indeed. This distro was going back to basics, and not flooding it’s users with fancy splash screens and progress meters, it was doing the needful, and it was doing it well.

I still have a lot more to learn about Arch, as I’ve only scratched the surface so far. I’ve been able to set up sound (with alsa) and video using the latest Nvidia drivers. I’ve configured Xmonad as my window manager, and have gotten a handle of how to query and install packages with “pacman”, the Arch package installer. The only real problem that I’ve run into is setting up CUPS for my printers. After some research, it seems that the version of CUPS (1.4.3-2) available in the Arch packages is the latest version available from the CUPS source repository, and that I may have to downgrade (to 1.3.9) it in order to get my printers working.

Overall, I like what I see so far with Arch. I expect to post more on my experiences with it as I learn.

I’ve been using Xymon (formerly known as “Hobbit”) for a long time.  In most situations, I have Xymon running in a redundant configuration, with two or more instances of Xymon working together to monitor a network.

Even though Xymon works very well, a single change to the primary server’s configuration file (the “bb-hosts” file) means that you have to make the same change to all other ‘bb-hosts’ files in all other Xymon instances.

There are some creative ways to eliminate the drudgery of updating all these files any time a change to the primary file is necessary.  One method, for example would be to have the master file exported via NFS to all the other Xymon server instances, and each of those instances would sym-link to that primary ‘bb-hosts’ file from their local mount of that NFS export.

I don’t like the NFS export idea, because if the primary server has a problem, and the NFS export is no longer available, all instances of Xymon would break - badly.

Instead, I’ve opted for automatically synchronizing the ‘bb-hosts’ file across all Xymon instances via the use of apache, cron, a sym-link, and a simple bash script.

Here’s  how it works:

• On the primary Xymon instance, sym-link ‘/home/xymon/server/etc/bb-hosts’ to ‘/var/www/bb-hosts’.
• On the other instances of Xymon, run a bash script which grabs the primary server’s ‘bb-hosts’ via HTTP, which does some simple comparisons, and over-writes the local Xymon ‘bb-hosts’ if changes are detected.
• Automat this script with cron.

Perhaps the trickiest part of doing this is the actual script used to grab, compare, and over-write the ‘bb-hosts’ file for the other instances of Xymon.  The script I’ve written below grabs the primary ‘bb-hosts’ file, and does a simple MD5 comparison with md5sum, and if it detects a change in the ‘bb-hosts’ file, it will send an e-mail to notify me that this change has occurred, along with details on what has changed.

Here’s the script:

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#!/bin/bash
 
REMOTE_BB_HOSTS="/tmp/bb-hosts"
LOCAL_BB_HOSTS="/home/xymon/server/etc/bb-hosts"
BB_HOSTS_DIFFS="/tmp/bb-hosts-diffs"
 
wget http://somewebhost.domain.com/bb-hosts -qO "$REMOTE_BB_HOSTS"
 
LOCAL_MD5=`md5sum $LOCAL_BB_HOSTS  | cut -d " " -f 1`
REMOTE_MD5=`md5sum  $REMOTE_BB_HOSTS  | cut -d " " -f 1`
 
#echo "$LOCAL_MD5"
#echo "$REMOTE_MD5"
 
if [ "$LOCAL_MD5" != "$REMOTE_MD5" ]; then
        echo "Generated by $0" > $BB_HOSTS_DIFFS;
        diff $LOCAL_BB_HOSTS $REMOTE_BB_HOSTS >> $BB_HOSTS_DIFFS;
        cp $REMOTE_BB_HOSTS $LOCAL_BB_HOSTS;
        mail -s "Xymon: monitor-02 bb-hosts updated" alertme@email.com < $BB_HOSTS_DIFFS;
fi

If you need a way to keep your Xymon ‘bb-hosts’ files in sync, something along the lines of the above script just may be what you’re looking for. If you’re currently accomplishing the same thing in an interesting way, please post a comment and let me know!

Currently Xmonad is my window manager of choice, because it’s clean, functional, and removes all the unnecessary crap that most modern desktops usually come with by default.

Although Xmonad is very cool, there are still some things that it’s lacking as far as functionality. Much of this is made up for by the use of Xmobar, Trayer, and other Xmonad compatible plugins and applications. I recently came across another one of these applications, and found it to be an exciting find. The tool is called Dzen.

Dzen is a desktop messaging tool which allows you to easily write some useful scripts, and have the output of those scripts become part of your desktop interface. Many examples of how this works are available on the Dzen webite, but some examples are as follows:

• CPU Monitoring graphs
• dmesg log monitoring
• Notification of system events which are commonly found in syslog
• E-mail or twitter alerts shown on your desktop as they come in
• Custom calendar alerts
• and much more..

Now this idea is not new - I remember there being a project called “OSD” (on-screen display) which essentially allows you to do the same thing. However, I think OSD was meant as more of an single message notification system, rather than the way that Dzen works, with master and slave windows, and the ability to implement menus, etc.

In any case, I decided to give Dzen a try, and am happy with the tool that I’ve been able to whip up. For the longest while, I wanted the ability for my xmonad environment to tell me, at a quick glance, what network mounts and removable devices I currently have mounted. I’m sure that this kind of information is easily available on many bloated desktops, including GNOME and KDE, but I was looking for something simple, small and configurable. Didn’t find it, so I ended up writing my own - with the help of Dzen.

Here are a couple of screenshots of how it looks:

Dzen “Active Mounts” widget (mouse out):

Dzen “Active Mounts” widget (mouse over):

I wrote the scripts fairly quickly, so I’m sure they could be written better, but I think they will provide those of you who are interested, a good example of how to implement a regularly updated notification widget with Dzen.

The scripts are written to check for changes in the mount list, and only update Dzen when a change is detected. It is written in two components:

1) A perl script which captures the mount information in the exact format that I want, and
2) a bash script which handles loading Dzen

Here’s the source code (perl script):

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#!/usr/bin/perl
 
# Written by J. Bobby Lopez <jbl@jbldata.com> - 27 Jan 2010
# Script to -be loaded- by the 'dzen-mounts.bash' script
# This script can also be run by itself, if you want to dump a
# custom plain-text table of your network shares or removable
# devices.
#
# This script is meant to be utilized the Dzen notification system
# Information on Dzen can be found at http://dzen.geekmode.org/
 
use strict;
use warnings;
 
use Data::Dumper;
use Text::Table;
 
my @types = qw( cifs ntfs davfs sshfs smbfs vfat );
 
sub getmounts
{
    my @valid_mounts; # to hold mounts we want
    my @all_mounts = split (/\n/, `mount`);
    foreach my $mount (@all_mounts)
    {
        foreach my $type (@types)
        {
            if ( $mount =~ m/$type/ )
            {
                push (@valid_mounts, $mount);
            }
        }
    }
    return @valid_mounts;
}
 
sub getsizes
{
    my @mounts = getmounts();
    my @list;
    foreach my $mount (@mounts)
    {
        my @cols = split (/\ /, $mount);
        my @df_out = split (/\n/, `df -h $cols[2]`);
        $df_out[1] .= $df_out[2] if defined($df_out[2]);
        $df_out[1] =~ s/[[:space:]]+/\ /;
	    my @df_cols = split (/[[:space:]]+/, $df_out[1]);
        push (@list, ([@df_cols]));
    }
    return @list;
}
 
my $tb = Text::Table->new(
	"Filesystem", "Size", "Used", "Avail", "Use%", "Mounted on"
);
$tb->load(getsizes());
print "Active Mounts\n";
print $tb;

And the bash script:

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#!/bin/bash
 
# Script to load Dzen with output from 'dzen-mounts.pl' script
# Written by J. Bobby Lopez <jbl@jbldata.com> - 27 Jan 2010
#
# This script utilizes the Dzen notification system
# Information on Dzen can be found at http://dzen.geekmode.org/
 
function mountlines
{
        LINES=`perl dzen-mounts.pl|wc -l`;
        echo "$LINES"
}
 
function freshmounts
{
        OUTPUT=`perl dzen-mounts.pl`;
        echo "$OUTPUT"
}
 
function rundzen
{
        OUTPUT=`freshmounts`;
        MOUNTLINES=`mountlines`;
        echo "$OUTPUT" | dzen2 -p -l "$MOUNTLINES" -u -x 500 -y 0 -w 600 -h 12 -tw 120 -ta l &
        PID=`pgrep -f "dzen2 -p -l $MOUNTLINES -u -x 500 -y 0 -w 600 -h 12 -tw 120 -ta l"`;
        echo "$PID"
}
 
function killdzen
{
        PID="$1"
        if [ ! "$PID" ]; then
            MOUNTLINES=`mountlines`;
            PID=`pgrep -f "dzen2 -p -l $MOUNTLINES -u -x 500 -y 0 -w 600 -h 12 -tw 120 -ta l"`;
        fi
 
        if [ "$PID" ]; then
            #echo "Killing $PID..";  # DEBUG STATEMENT
            kill "$PID";
        fi;
}
 
function checkchanges
{
    while true; do
        NEW=`freshmounts`;
        #echo "$NEW - new";  # DEBUG STATEMENT
        if [ "$OLD" != "$NEW" ]; then
            killdzen "$PID";
            rundzen;
            #echo "$PID started";  # DEBUG STATEMENT
            OLD="$NEW";
            #echo "$OLD - old updated"  # DEBUG STATEMENT
        fi
        sleep 1;
    done
}
 
checkchanges

You can also download the scripts in a tgz archive here. Enjoy!

Well, my Blackberry is officially offline because of a nationwide blackberry outage currently taking place. I use my Blackberry to receive messages from monitoring systems at VMware, so I’m severely pissed. I haven’t received any e-mails for several hours! The only way I knew that something was wrong, is that I have a sanity e-mail sent to myself every 2 hours. When I don’t see that e-mail, something evil is happening.

For a brief moment, I thought I was going to have to call and bitch at Rogers, but they’re not at fault this time.

Real time updates on the situation via Twitter is nice, but a working Blackberry would be nicer.

Long time linux/unix hackers know of the plethora of window managers and user interfaces that have been and currently are available for Linux and BSD operating systems.  I’ve had great times in the past trying out different window managers such as Elightenment, Sawfish, Black Box, IceWM, xfwm, KDE, Gnome,  and others.  These days the two most popular which are shipped with the more popular distributions (Fedora, Ubuntu) are KDE and Gnome.

However, I remember back in the day when I was using a Enlightenment, or Ratpoison, doing strange and cool things (at the time) like applying transparencies to your windows and modifying the the window borders to be anything but normal and square.

I used to share screenshots of my desktop with others who are also into “desktop eyecandy”, where I’d have floating or docked window maker panels, and monitoring applets anchored to the desktop as if they were part of the background wallpaper.. and this was around 1999.  It was fun times.

One of the more interesting things that I was into at the time was increasing the efficiency and usability of my desktop by trying to reduce the need to reach for my mouse.  I’ve been very accustomed to this already being user of vi and the GNU Screen terminal multiplexor, but the window managers never seemed to try to attain the same level “hacker cool”.  That is, of course until I came across Ratpoision. Ratpoison was exactly what the name implied, a window manager that killed your dependency on the mouse (or rat).  It was awesome, but it wasn’t scalable and didn’t evolve much to keep up with modern technological advancements and requirements such as multi-monitor support.

I recently thought that those days were long lost, until I recently had the urge to streamline my desktop environment.  I now have a 28″ Monitor, and was certain there was a better way to interact with the desktop than the standard Ubuntu/Gnome environment.  So I went looking.  I started looking of course at things I was already familiar with - I looked up Ratpoision to see if there were any major improvements over the years.

I took a look at a Ratpoison again, but it was showing it’s age.  I looked at it’s successor, Stumpwm, but I didn’t feel the love.  Then I tried out Xmonad, created by Spencer Janssen, Don Stewart, and Jason Creighton - and written in Haskell.  I immediately fell in love.

If you haven’t used GNU Screen, Gnome Multi-Terminal, Ratpoision, or any minimalist Window Manager before, then it will be hard to explain why Xmonad is worth your time.  Instead, visit the Xmonad website here: http://www.xmonad.org/

Here are some suggestions on how get Xmonad working on Ubuntu 8.10:

Install Xmonad:

apt-get install xmonad

We’re going to create another X window session, so that we don’t mess with your existing one. That way, if you don’t like Xmonad, you can go back to using your existing window manager without worrying about breaking your configuration.

Set up your second X window session. Press “ctrl + alt + f2″ - this will take you to the command-line terminal where you will start your second X session. Start the session using following command:

xinit -- :1 vt12

This will start up another X session which will sit at virtual terminal 12 - meaning that you have to press ‘ctrl-alt-F12′ to get to it.

Once at your new X session, you should see nothing more than an plain old xterm window. Type “xmonad’, and the terminal window should now be maximized. Xmonad is now running.

Type ‘man xmonad’ to view the help documentation on how to use it.  It’s pretty straight forward, and a joy to use!