Remove unnecessary services on your PC or server

Whether it is a Windows PC, Cisco router, switches, Linux machine or network enable device, it is recommended to stop unnecessary services that are run by default. Every running, but unused, service on your system maybe a possible means of attack. Users may not even be aware that many of these services are running.

It is important to know the security implication of any network service before enabling it in. For example, a telnet client running on another device on the network can easily establish a telnet session to a system where telnet service is enabled; it needs only the IP address of the system and the port or socket number of the network service running on the system. The rule of thumb for TCP and UDP ports is: Turn off any services or listeners that you do not need for your application to function. One way to check the list of ports running on your system is to go to one of the many web sites that can run a remote scan of your system and tell you how secure the system.

FlvPlayer4Free - play FLV file downloaded from Youtube

One of the way to download video from Youtube to your computer is to use the following web site:

http://clipnabber.com/

Just paste the Youtube web page address (URL) for the video into the Paste URL and then click FLV download link to download the video in FLV format.

The FLV file downloaded can then be view using FlvPlayer4Free. FlvPlayer4Free is a freeware that allows users to easily play their favourite FLV files in the hard disk or from internet.

How to set default printer in Linux or Unix

If you are using terminal setup in Unix systems like Linux, you can configure your default printer by:

1. csh shell version (by editing ~/.cshrc or ~/.tcshrc configuration files%2y

setenv PRINTER your-printer-name

2. bash shell version (by editing ~/.bashrc configuration file)

export PRINTER=your-printer-name

How to generate PS file in Windows environment

In order to create a Postscript (PS) file from Windows applications: simply print from the application, selecting a postscript printer and using the printing option "print to file".

A dialog box will open, allowing you to choose the folder in which you wish to create the PostScript file. Choose a name for the file (a .prn extension will be appended to the filename). When you select Save, the printer driver will save the Postscript file in the location you select instead of actually sending the postscript file to the printer. You may need to change the file extension to .ps after file is generated.

However, very likely, using the printer driver for your own printer will result in files that are targeted at that printer, and hence not completely portable. To achieve portability, you will need to install and use another printer driver. Also you may not have any postscript printer with you at the moment. The solution to this is to install a virtual postscript printer, i.e. install printer drivers without actually having the corresponding printer.

Ctrl-Shift-Eject lock Mac screen

The Ctrl-Shift-Eject shortcut key is useful for Mac users to put the Mac to sleep mode and password protected. This is something like the Ctrl-Alt-Delete feature in Windows which locks the Mac screen. Users will need to key in password in order to access the Mac again.

How to restart CUPS in Linux

Simply execute the following command will restart CUPS (Common UNIX Printing System) service in Linux like Ubuntu:

#/etc/init.d/cupsys restart

By the way, CUPS is the standards-based, open source printing system developed by Apple Inc. for Mac OS X and other UNIX-like operating systems.

How to solve "Another blog is already hosted at this address"

Sometime when you try to publish a custom domain like ipcnetworking.com on Blogger, you may get the message "Another blog is already hosted at this address."

Most of the time, this is due to your DNS setting. Anyway make sure that you stop the web service of Google Apps if you happen to use this service.

One way to overcome this problem which I did with my sites was to configure my DNS as:

mydomain.com.          3600 IN CNAME ghs.google.com.
www.mydomain.com. 3600 IN CNAME ghs.google.com.

With this configuration, you have a "CNAME" referral which points directly to a Google server. When the Blogger script verifies that the domain URLs both point to Google, it can proceed with confidence.