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Arthur C. Clarke and the Dot Com Lifestyle

Johan Cyprich — Tue, 07 Sep 2010 07:56:16 +0000

Sir Arthur C. Clarke is one of the most famous science fiction authors and was known as one the “Big Three” of science fiction (the other two were Robert A. Heinlein and Isaac Asimov). His book, 2001: A Space Odyssey, and the film made from it inspired a whole generation of children to pursue engineering and the natural sciences.

Predicting the Future in 1964

In addition to his writing ability, he had a talent for predicting the future. The video clip below shows him predicting what the future may hold 50 years later. This is from a BBC programme called Horizon made in 1964. At the time, there was no Internet and its forerunner, ARPANET, wouldn’t go online until 1969. He predicted what is becoming more and more common today: people working from home and making money online. Instead of going to a physical location to work, they would be able to work anywhere and communicate with clients/co-workers through the Internet.

Highlights of the Video

“A world in which we can be instant contact with each other, wherever we may be, we can contact our friends anywhere on earth even if we don’t know their actual physical locations. It will be possible in that age, perhaps only 50 years from now, for a man to conduct his business from Haiti or Bali just as well as he could from London. In fact, if it would prove worthwhile, almost any executive skill, any administrative skill, even many physical skills could be made independent of distance. I am perfectly serious when I suggest that one day we may have brain surgeons in Edinburgh operating on patients in New Zealand. When that time comes, the whole world would have shrunk to a point and the traditional role of a city as a meeting place for man would have ceased to make any sense. In fact, men will no longer commute, they will communicate. They won’t have to travel distance any more, they’d only travel for pleasure.”

The Dot Com Lifestyle for Everyone

We’re not quite at the point which Clarke describes and it will probably be another decade or two for it to happen. Canada and the US are increasingly becoming information and services based which is ideal for working online. The only real challenge is the acceptance of working this way and if the growth of social networking is any indication, we’re well on our way there.

Changing Report Server URL in DFS

Johan Cyprich — Tue, 17 Aug 2010 22:03:22 +0000

Adenium Systems tech support recommended that an internal URL for the DFS report server is used as opposed to an external one. This is likely due to increased performance in accessing the URL.

To change this URL, open Library Manager and right click on the Library and then select the option to edit. Go to the Settings tab and edit the Report Server URL (see below) so that it has an internal URL.

Go back to the Description tab and add an internal URL (i.e. 192.168.147.7) here. If you leave this blank, DFS will use the external URL for the Internal Portal URL when you preview the planroom in the Library Manager. Each time you edit something in the library settings, you need to set the IP here or it will save as blank. The Internal IP Address always starts off as a blank and it will save like that if you press the OK button.

Setting Up URL Rewriting for Apache in Linux

Johan Cyprich — Tue, 17 Aug 2010 18:23:32 +0000

Search Engine Friendly (SEF) URL’s are very common today with the widespread use of content management systems (CMS). These are URL’s that look like http://www.website.com/about as opposed to the conventional http://www.website.com/about.html. An SEF URL in a CMS would replace something like http://www.website.com?id=34.

The advantages of SEF over conventional URL’s is that they are shorter and easier to send to people, and they also increase the security of a web site by hiding components are being used on a page. In its webmaster guidelines, Google recommends caution in using dynamic web pages:

If you decide to use dynamic pages (i.e., the URL contains a "?" character), be aware that not every search engine spider crawls dynamic pages as well as static pages. It helps to keep the parameters short and the number of them few.

CMS users need to take extra steps for content presentation:

If your company buys a content management system, make sure that the system creates pages and links that search engines can crawl.

A CMS may generate a long and complex URL which can prevent a search engine from indexing it. An SEF URL will shorten the URL and remove the ? character which sets off warnings with web crawlers.

The first thing that you need to do is determine if mod_rewrite is installed in Apache. You can find this by using the phpinfo () function (see phpinfo.php for example). This function will display a long list of settings that PHP and Apache are using. Scroll down to apache2handler and check if mod_rewrite is in Loaded Modules.

[== Code: phpinfo.php =================================]

PHP Info

[== Code ==============================================]

If the module is installed, but URL rewriting doesn’t work, you’ll need to make minor changes to the httpd.conf file located at /etc/httpd/conf/. Change AllowOverride to All (see httpd.conf below). You may need to change this in several place in the configuration file before URL rewriting works.

[== Code: httpd.conf ==================================]

# AllowOverride controls what directives may be placed in .htaccess files.
# It can be "All", "None", or any combination of the keywords:
# Options FileInfo AuthConfig Limit
#
AllowOverride All

[== Code ==============================================]

After you made the changes, you’ll need to restart Apache. If your not sure how to do this, see How to Start, Stop, and Restart Apache in Linux. Test mod_rewrite by loading the following files (.htaccess, one.html, two.html) on your web server. The RewriteBase setting in .htaccess should point to the subfolder in your web server (i.e. /rewrite/) if the default setting below doesn’t work. When you browse to one.html, you should be redirected to two.html.

You can download the code below here.

[== Code: .htaccess ===================================]

RewriteEngine On
RewriteBase /
RewriteRule ^one.html$ two.html

[== Code ==============================================]

[== Code: one.html ====================================]

One

This is the number one.

[== Code ==============================================]

[== Code: two.html ====================================]

Two

This is the number two.

[== Code ==============================================]

How to Start, Stop, and Restart Apache in Linux

Johan Cyprich — Thu, 12 Aug 2010 21:58:15 +0000

At various times, you will need to manually start and stop Apache. This could be due to making changes in the httpd.conf file which requires a restart, or the web server could be experiencing problems. You can perform these commands in a Linux terminal with httpd.

To start Apache, type
/etc/init.d/httpd start
To stop Apache, type
/etc/init.d/httpd stop
To restart Apache, type
/etc/init.d/httpd restart

Setting the ServerName

One problem that you may encounter when you start or restart Apache is that the domain name may not be defined. This can easily be fixed by opening the httpd.conf file in the /etc/init.d/conf/ folder and editing ServerName (it may have been commented out). See below for error:

Give a meaningful name to this variable and the warning will no longer be displayed when starting Apache (see below):

# ServerName gives the name and port that the server uses to identify itself.
# This can often be determined automatically, but we recommend you specify
# it explicitly to prevent problems during startup.
#
# If this is not set to valid DNS name for your host, server-generated
# redirections will not work. See also the UseCanonicalName directive.
#
# If your host doesn’t have a registered DNS name, enter its IP address here.
# You will have to access it by its address anyway, and this will make
# redirections work in a sensible way.
#
ServerName webserver

Display a List of Installed Modules in Apache

Johan Cyprich — Wed, 11 Aug 2010 22:29:28 +0000

If your having problems with a feature in Apache, such as URL rewriting, you can check if the rewrite_module was installed. The following procedure works on a Linux terminal with Apache 2.x.

httpd –l
Lists compiled (static) modules.
httpd –M
Lists shared/dynamic modules. You can also use apachectl –D DUMP_MODULES.

Set Windows Workgroup in Linux

Johan Cyprich — Fri, 06 Aug 2010 15:00:00 +0000

A Linux computer can connect to a Windows network through Samba, which can be easily in installed in Fedora and other distributions. You will need to enter the workgroup that the Windows network uses in order to connect to it. This information can be entered in the smb.conf file found at /etc/samba.

You can edit the file with the following command:

vi /etc/samba/smb.conf

Scroll down until you find workgroup (see below) and change the name to match your Windows workgroup setting.

How to Fix 99% of Computer Problems

Johan Cyprich — Thu, 05 Aug 2010 21:06:09 +0000

It never ceases to amaze me how often people automatically contact their IT department or technical support when problems occur on their computer. Typical issues are programs freezing, not seeing a folder on a network, or e-mail not sending. While some of these may be due to hardware failures, most often they are very simple to fix.

So, here is my list of things to do (not in any particular order):

1. Reboot the Computer

Software isn’t perfect. There are many components in an application which interact with each other and the operating system and things can go bad and crash. Or the application may just stop working correctly. Closing the program and running it again may be enough to fix this, but if the problem is with .NET, Java, or a memory leak, rebooting would be the best solution.

2. Press the F5 Key

An error can occur when trying to view a web site, or you can’t find a file that a coworker just placed in one of your folders. Pressing the F5 key will refresh a web browser or file browser and you’ll get an updated view of it. Most applications have options to refresh content and have a context menu (right click in a blank area) that will give you the option to refresh.

3. Wait a Little While

If your e-mail isn’t sending, the problem may be with your internet provider. They may be down or doing maintenance. Instead of phoning them (after being on hold for 10 minutes) and complaining, give them some time to fix the problem. Phoning them won’t fix the problem faster. You can be assured that they are doing the best they can to get back online because they want your continued business.

4. Learn More

This isn’t really a quick fix, but learning how to use your computer and software can really go a long way in being productive and working well. I find that most people know just how to push buttons but don’t really understand what’s going on. So when any problem occurs, they don’t try to think about how to fix it and call someone more technical for assistance.

Getting the PowerShell Version

Johan Cyprich — Wed, 04 Aug 2010 20:37:35 +0000

To find out which version of PowerShell is installed in your computer, you need to do more than just run it. When you start the command line interface, your lead to believe that version 1.0 is installed from the directory location displayed in the dialog box.

The text in the dialog box shows C:\WINDOWS\system32\windowspowershell\v1.0\powershell.exe, which would make it seem like you were running version 1.0. The best way to determine which version is installed is to run the PowerShell command line interface and execute the following command:

$Host.Version

This will give you the major and minor versions, along with the build and revision.

SendMail Function for PowerShell

Johan Cyprich — Tue, 27 Jul 2010 22:13:12 +0000

The SendMail function for PowerShell will send an e-mail through an SMTP server. I’m currently using it for backing up a web server to a virtual machine and sending a confirmation by e-mail on the status of the backup.

Usage is very simple:

SendMail Host From To Subject Message UserName Password

The Host is the mail server address, i.e. smtp.mail.com. The From and To are the sender and receiver of the e-mail. The Subject and Message are the title and contents of the e-mail. If authentication is required, then enter values for the UserName and Password, otherwise make them blank using single quotes, i.e. ‘’.

The function will return a boolean value: true if the mail was sent successfully, false if it couldn’t be sent. See example in this post.

SendMail Code

The following is the code for the SendMail function which can be pasted in your PowerShell application.

[== Code ==============================================]

function SendMail ([string] $sHost, [string] $sFrom, [string] $sTo, [string] $sSubject, [string] $sMessage, [string] $sUserName, [string] $sPassword)

####################################################################################################
# PURPOSE:
#   Sends an e-mail to an SMTP server. It will also authenticate to the server if a user name and
#   password are sent to the function. If authentication is not used, leave $sUserName and $sPassowrd
#   blank, i.e. ”.
#
# PARAMETERS:
#   $sHost (in) – host name of mail server
#   $sFrom (in) – e-mail address of mail sender
#   $sTo (in) – e-mail address of mail recipient
#   $sSubject (in) – subject title of message
#   $sMessage (in) – message sent to recipient
#   $sUserName (in) – user name for authentication
#   $sPassword (in) – password for authentication
#
# RETURN:
#   True – mail was sent succesfully
#   False – mail was not sent
####################################################################################################

{
[bool] $bSuccess = 1 # was mail sent without problems?

$SmtpClient = new-object system.net.mail.smtpClient
$smtpclient.Host = $sHost

# Authenticate only if a user name and password are set.
if (($sUsername -ne ”) -band ($sPassword -ne ”))
{
$Credentials = new-object System.Net.networkCredential

    $Credentials.domain = ""
    $Credentials.UserName = $sUserName
    $Credentials.Password = $sPassword
    $SMTPClient.Credentials = $Credentials
} # if (($sUsername -ne ”) -band ($sPassword -ne ”))

# Send the mail.
try
{
$smtpclient.Send($sFrom, $sTo, $sSubject, $sMessage)
}
catch
{
$bSuccess = 0
}
$bSuccess
} # SendMail

[== Code ==============================================]

Example of the SendMail Function

This is an example of how the SendMail function should be used.

[== Code ==============================================]

$bSent = SendMail ‘smtp.mail.com’ ‘sender@website.com’ ‘recipient@website.com’ ‘Test’ ‘This is a test.’ ‘sender@website.com’ ‘abc123′

if ($bSent)
{
"Mail sent successfully."
}

else
{
"Mail not sent."
}

[== Code ==============================================]

You can download the SendMail code and example here.

How to Redirect Web Pages (Part 1)

Johan Cyprich — Tue, 27 Jul 2010 01:43:02 +0000

Redirecting web pages becomes necessary when a web site is updated and old pages are replaced with new ones. This is very common when a site is upgraded to a CMS which typically displays pages as folders (i.e. www.website.com/about) as opposed to www.website.com/about.htm.

Its important to redirect old pages to new ones because if the old page is bookmarked in a web browser, it will lead to a 404 error page and the user will probably not try to manually change the URL to go to the home page. Also, its better for SEO to have a consistent page structure in your site.

Redirection in IIS

The easiest way to redirect web pages is through the Management Console in IIS in Windows. Find the page you want to redirect, right click on it, and select Properties. This will give you the following dialog box.

Select the A redirection to a URL radio button and enter the URL of the new page in the Redirect to textbox. Press the OK button to save the settings. When the page is viewed in a web browser, it will automatically redirect the browser to http://www.website.com/about.

Redirecting Using HTML

You can also give instructions to redirect in a web page. The page that needs to be directed will contain the code below. The meta tag should be enough to do the redirect, but on some web servers it may not work. The JavaScript below will redirect only if JavaScript is enabled on the user’s web browser. The meta redirect is done on the server side and doesn’t require any settings on the user’s part.

In Part 2, I’ll show you how to redirect web pages in Apache using .htaccess.