First, lets setup the environment. I use VI as my text editor on Linux and you can view my “60 second VI tutorial” on here as well. To ensure that VI will be our crontab (cron table) editor we will need to edit your “.profile” file for whatever user you are going to be logged in with (typically root).

vi /root/.profile

Add one of thefollowing lines above the second fi to match your preference.

export EDITOR=/usr/bin/vi #if you have just VI installed
export EDITOR=/usr/bin/vim.basic #if you have VIM installed

Ensure that you save it with :wq.

Now that we have that out of the way, lets start scheduling tasks.

Since backups are traditionally something that you would want to automate or schedule, I’ll use it as my main example but first I’ll break down the cron scheduling syntax.

0 2 * * * root tar czf /var/backup/www.tar.gz /var/www >> /dev/null 2>&1

With the above example and the table of what each field does, you get can put together that at 0200 or 2:00 AM every day root will be running “tar czf /var/backup/www.tar.gz /var/www >>/dev/null 2>&1″ which is telling tar to tar up /var/www into /var/backup/www.tar.gz and /dev/null 2>&1 is a way to have the command put any output into a “trash can” if you will  Alternately you can specify a log file for that output to go with “>> /var/log/cronforcommand.log 2>&1″.  The * in a schedule means to omit that portion of the schedule.

That one was pretty basic so I’ll get a little more complicated now.  Matter of fact, I’ll just skip the user and command to execute from now on and focus on the command structure for scheduling with cron

EXAMPLES:

Every Minute – * * * * *

Every 5 Minutes – 0,5,10,15,20,25,30,35,40,45,50,66 * * * *

Every 5 Minustes (Simple) – */5 * * * *

Every Hour – * */1 * * *

Every 2 hours – * */2 * * *

Every Day @2:00 AM – 0 2 * * *

Every Day @ 6:00 PM – 0 18 * * *

Every Sunday @ 3:15 AM – 15 3 * * 0

On Feburary 11 @ 10:00 PM – 0 22 11 2 *

That pretty much covers the majority of typical uses for cron. Obviously this is a very powerful tool and can do so much more but for this post, I think it’ll do.  If I messed anything up , please let me know.  Enjoy.

First, let’s make sure we have the right packages installed.

apt-get install openssh apache2 apache2.2-common php5

Now let’s enable SSL for apache2

sudo a2enmod ssl

Now lets create the server SSL key.

cd /etc/ssl/private
openssl genrsa -des3 -out dns.server.com.key 1024

Ok, now that we have the key, let’s create the CSR to be given to the CA.

openssl req -new -key dns.server.com.key -out dns.server.com.csr

It will prompt you for the passphrase and some other bits of information.  The most important one is site name.  This must match the name of your server.  Something like mail.domain.com or www.domain.com would be appropriate here.

The CSR can now be uploaded to whatever CA you choose.  I use GoDaddy because they are so cheap.

If you do not want to purchase a certificate you can create your own self signed cert with the following command.

openssl x509 -req -days 365 -in dns.server.com.csr -signkey dns.server.com.key -out dns.server.com.crt
cp /etc/ssl/private/dns.server.com.crt /etc/ssl/certs

Now that we have the cert created, let’s configure Apache to use it. Add the following 3 lines to your website configuration.  The default one is located in /etc/apache2/sites-available/default.

SSLEngine on
SSLCertificateFile /etc/ssl/certs/dns.server.com.crt
SSLCertificateKeyFile /etc/ssl/private/dns.server.com.key

Save that config file and enable Apache to listen on 443 for HTTPS traffic.  Add the following line to /etc/apache2/ports.conf

Listen 443

Restart your Apache2 process and you should have a fully functional SSL enabled website.

/etc/init.d/apache2 force-reload && /etc/init.d/apache2/restart

vi /etc/network/interfaces - opens /etc/network/interfaces in vi

i - insert
/ - search
G - [Shift] g - go to bottom of page
dd - delete the line
d <- or d -> - d [left or right arrow] delete 1 character in that direction
10G - 10 [Shift] g - move to line 10 (obviously number can be replaced)
10dd - delete 10 lines from cursor and below (again, number can be changed)
:q - quit (no changes may have been made)
:q! - quit (do not save changes)
:wq - write quite (save and quit)
:w - write (save)

Ok, now that you have mastered the basics of vi, please refer all other needs to the link provided above.  Hope you like vi as much as I do.

NOTE:  Ubuntu (and maybe debian) have a few things that the built in vi program have that seem a little strange.  I usually install vim just to be safe.  to do this run sudo apt-get install vim-full.


apt-get install openssh-server openssh-client

That’s it. If you want to play around a little more you can configure Ubuntu’s firewall in just a few simple steps as well. In my example I will enable tcp/80, tcp/443, tcp/22 and udp/53 inbound.

ufw disable
ufw allow 80/tcp
ufw allow 443/tcp
ufw allow 22/tcp
ufw allow udp/53
ufw enable

And then you can validate what you have entered with:

ufw status

The output will be similar to this:

Firewall loaded

To Action From
– —— —-
80:tcp ALLOW Anywhere
443:tcp ALLOW Anywhere
22:tcp ALLOW Anywhere
53:udp ALLOW Anywhere

And that’s really all I do…it’s definately not much but it will be enough to get you started connecting remotely.

Instead of going command line or even installing the package manually, I chose Fonality’s trixbox CE which is free and is an all-in-one solution for IP telephone. At least on the server side. Install is straight forward, answer a few questions and it’ll eventually reboot and you’ll have a functioning Asterisk server with FreePBX installed as well as some other goodies.

Once you have trixbox up and running, you login to the web GUI and start configuring. Mine is http://192.168.1.10. Under FreePBX I had to configure 3 things:

1. Trunk – This is to tell Asterisk who to connect to for inbound and outbound calling. You have to configure things like registration strings, usernames, passwords, and any specific information for your provider. I have attached my configuration to this post.

2. Extension – I created a new extension (201) to allow my Sipura SPA-1000 to register to my trixbox. The setup on that was fairly easy with just an extension number, password and a few options for voicemail and fax.

3. Inbound/Outbound routes – Tell Asterisk to use a specif trunk for outbound calls and specify what dial patterns you want it to pick up on. Then on inbound you need to tell Asterisk what extensions to ring when a call is coming in.

That’s it. Really, really simple. This was not my first time with trixbox but it was the first time that I actually got it to work. I was quite surprised how clean the calls sound through the Internet, I was expecting to need to do QoS to get it right. I’ll still do that but so far I have not needed to.

My next goal is to get some of the advanced features running. Music on hold, failover call routing, etc.

Home Computer

I have a Panasonic Toughbook laptop running Ubuntu 7.04 that I really haven’t modified too awful much because I like the look and feel of the OS as it is. Here’s a list of things that I use everyday or every so often to accomplish a task without spending any money.

Operating System – Ubuntu 7.04 – Stable, clean, easy to install, based on GNOME and very well supported by the community. I would say that the forums for Ubuntu are better than most and for some reason, the users of Ubuntu are much nicer than that of Red Hat and others.

Blogging – Blogger.com attached to my Gmail account (I do my own hosting)

Firewall - pfSense – I mentioned this a few post’s ago. I absolutely love this firewall.

Document Management – Google Doc’s and Spreadsheets – This one is really neat, you can upload your Microsoft Office Word and Excel files as well as OpenOffice equivalent documents up to Google, edit them, and even save off as PDF documents if need be.

Music – Pandora.com – This site has been around for a little while now, It allows you to basically make your own radio station, and it dynamically learns what music you want to listen to. A side spawn of this project is Squeezebox which allows you to turn your music library into a radio station with streaming music.

Chat – Gaim – It’s easy to use, installed by default on Ubuntu, and supports multiple accounts. On Linux and Windows you can use Pidgin and for Mac OS X you can use Adium.

VoIP – Twinkle – So far this is the best SIP capable client for Linux I have found. You can installed it through apt-get or Synaptic on Ubuntu or download it here. On Windows and Mac OS X I use X-Lite from CounterPath. I would say X-Lite is the best of the two but the Linux version sucks in my opinion.

PBX – trixbox – I just started using this because I’m trying to get my company or rather the company I work for into a new market so that we can make some more money as a company which personally helps me through profit sharing. Though, if I didn’t get that last bit, I would still peruse doing phone VoIP systems because I think they are interesting. I have it installed on an old PIII 500 with 256Mb of ram and it suits the needs of my wife an I just fine. A larger scale deployment would need a better server though.

Email – Gmail and Evolution – I just started using Evolution about a month ago because Outlook Web Access on Microsoft Exchange 2003 sucks when viewed from Firefox. Damn Microsoft. Kidding. Evolution seemed to be a logical choice for me because well, it was already installed on my computer and quite frankly I needed a way to check my mail. Sounds like a match made in heaven. Gmail, as you all probably know, is free and has cool features like web sharable calendars, documents and photos. You will probably see a trend here for me liking everything Google.

I think that’s enough for now. I’ll make a part 2 to this one pretty soon with quite a few more added programs and services that I use everyday for free. Compute free or die.

To get the wireless hardware working with the OS most people recommend NDISWrappers but the easiest and most supported was is to use Synaptic (the package manager) to install bcm43xx-fwcutter which is nothing more than the firmware that the kernel needs to load during the boot process to make the Wireless NIC usable. After installation just reboot and the viola you have a working Broadcom wireless NIC which supports pretty much any encryption method available.

Well, I figured I would dedicate a post to how much I truely enjoy the OS vs it’s or Linux competitors as well as the big Microsoft. The installation disk is easily available via http://www.ubuntu.com where you can either download it or have 1 or more copies sent to you via snailmail (I get 25 because I’m a consultant). On the install CD (not DVD) there are a few cool features that make the product stand out from the rest like a suite of open source Windows apps that can be installed directly from the CD to include Firefox, Thunderbird, Clam AV, and others. Truly unique. Then when you boot from the CD you actually boot to a live distribution where you can either use the live CD to see if you will actually like the or install it to your hard drive via a very intuitive wizard. The wizard asks you a few non technical questions and guides you through the install. You can dual boot with Windows or another OS or just wipe the drive and start fresh.

On a side note, because of how well setup the live CD is, you can actually read and write to the NTFS, FAT or other drive that you have in your computer as a quick and easy disk recovery tool. Still not impressed. Ok, I really haven’t told you very much but for the novice user these fundamental options make the OS very attractive. After you go through the install, you reboot and come up to a login window and then into the operating system. The only thing that my laptop needed done in addition to the OS install is the installation of the Broadcom WIFI card firmware for my specific hardware which was easily done in Ubuntu’s intuitive package manager, Synaptic. Synaptic is a front end for apt-get that makes installing and updating packages a synch.

I usually judge a product by it’s “Out of the Box” features. As for Ubuntu, the OS installs, Firefox, Evolution Mail, Gaim, OpenOffice, graphics rendering software, a photo viewer, a suite a games, and a terminal services client. So in my opinion, it’s already a step ahead of Microsoft. Accessing shares and other network resources is quite simple just like in XP and has a neat feature that saves the user name and password for a particular network resource in it’s password manager.

I plan to do a few more blog entires regarding the use and utilization of Ubuntu in the home, business and corporate environment on both the client and server end of the spectrum. As the OS is still a Linux derivative, it can run Postfix, Sendmail, Apache, MySQL, Spam assassin, and all of the server centric applications that we rely on everyday. Hope you all at least give the OS a try, I’ll have my first Ubuntu “how-to” on here soon for your enjoyment.