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If you apt-get install sysstat, and sar returns:

Sar needs to be enabled before it can be used. The error message in this case is completely useless, and the solution I have found is as below:

Enable sysstat data collection by doing

or manually by changing value of ENABLED from "false" to "true" in "/etc/default/sysstat".

Then start sysstat via:

Check "/var/log/sysstat/" for the missing file.

Run sar after about 10 minutes to see the collected data.

Package mpack is required in order to extract the backup contents.

The result is a set of tar and sql files that contain domains' directories and databases. Untar the directory as needed.

For example, to restore the httpdocs folder for the DOMAIN.TLD domain:

Reference:

How to extract web files, databases etc from Plesk backup manually?

I was getting the below error in my mail error log files:

Apparently a bug in ubuntu dapper, where libmail-spf-query-perl depends on libsys-hostname-long-perl.

Doing an `apt-get install libsys-hostname-long-perl` resolved the issue.

1. Free web hosting service: is free, (sometimes) advertisement-supported web hosting, and is extremely limited when compared to paid hosting.
   
2. Shared web hosting service: one's Web site is placed on the same server as many other sites, ranging from a few to hundreds or thousands. Typically, all domains may share a common pool of server resources, such as RAM and the CPU.
   
3. Reseller web hosting: allows clients to become web hosts themselves. Resellers could function, for individual domains, under any combination of these listed types of hosting, depending on who they are affiliated with as a provider.
   
4. Virtual Dedicated Server: slicing up a server into virtual servers. each user feels like they're on their own dedicated server, but they're actually sharing a server with many other users.
   
5. Dedicated hosting service: the user gets his or her own Web server and gains full control over it (root access for Linux/administrator access for Windows); however, the user typically does not own the server.
   
6. Colocation web hosting service: similar to the dedicated web hosting service, but the user owns the server; the hosting company provides physical space that the server takes up and takes care of the server. This is the most powerful and expensive type of the web hosting service. In most cases, the colocation provider may provide little to no support directly for their client's machine, providing only the electrical, Internet access, and storage facilities for the server.
   
7. Clustered hosting: having multiple servers hosting the same content for better resource utilization.

robot.txt file is your invitation to the search engines when they send a spider to crawl through the pages of your web-site. These spiders are out and about on the web gathering information that contributes to your search engine ranking.

There are different kinds of robots/spiders/crawlers, some are just taking inventory, some are looking for what's new, but whatever kind of robot they are, when they hit your site, you have some control over what they do, and you need to give them some instructions.

You can block bots, you can tell them which pages they can and can't look at and you can tell them when you'd like them to return.

There are probably a thousand free robot.txt generators out there and here is one you can use: 1-hit.com

If you want to generate your own file read on...

I had an old computer with linux installed and had forgotten the root password for it. Unfortunately, I did not have my favourite handy-dany knoppix cd around but did remember that I could get a shell access by appending "init=/bin/bash" to the lilo/grub boot loader, which should be enough to get in and reset the root password.

DISCLAIMER -- I do not take any responsibility for your actions if you go and try this on your friends machine!!

1. Press Ctrl-Alt-Del to shut down the system in an orderly fashion.
2. Reboot the system and when lilo/grub boot loader get to the point where you select the various installed kernels on the system, type the letter "a" for "append".
3. You will get a prompt like this to add boot options to the boot string found in your lilo/grub conf file:

   grub append> ro root=LABEL=/

4. Append "init=/bin/bash" to it to look like this.

   grub append> ro root=LABEL=/ init=/bin/bash

   This tells the kernel to drop to a root prompt bash shell instead of starting the "/sbin/init" process.

5. The root filesystem is currently mounted read only which needs to be changed to read/write prior to resetting the password.

   # mount -o remount,rw /

6. Now that the file-system is remounted read-write, go ahead and type `passwd` to change the root password.

   # passwd

7. Since "init" isn't running to safely take down the system, remount the system to read only prior to shutting down the system.

   # mount -o remount,ro /

8. You can now safely press on the power button to shutdown the sytem.

I was having a hard time getting m3u (MP3 audio -- streamed) files open up in my external xmms audio player instead of the the default mplayerplug-in and found out that firefox by default hides the plugins without any extensions, as the mp3 playlist was being created dynamically with php and the mime-type fed via the header.

The work-around was to disable the default firefox config settings and change the option for streamed mp3 audio to be opened with xmms instead.

The steps are outlined below:

1. Type "about:config" on the address bar to get to firefox config settings.
   
2. Do a filter search for "hide_plugins" and double click on "browser.download.hide_plugins_without_extensions" to change the settings value to "false".
   
3. Open up "Edit > Preferences", go to the "Downloads" area and click on "View & Edit Actions".
   
4. It should now list all the "File Type". Do a search for audio and change the "MP3 audio (streamed)" to open up in the external xmms player.

See other posts on Firefox.

Sang Shin is offering a free ten-week course on Ajax, starting on the 4th of August, 2006.

It will cover fundamental technologies and some of the popular libraries and frameworks out there. Looking at the curriculum, there's a Java focus on the server-side -- DWR, Wicket, JMaki, JSF, and GWT...

Below is an abstract of what it involves:

o The Web is going through the second wave of its evolution and some people call it Web 2.0. Whether Web 2.0 is considered a hype or not, there are indeed a set of concrete technologies such as AJAX (Asynchronous JavaScript + XML) that make the Web of today a lot more interactive, responsive, exciting and useful than it used to be.

SmoothWall Express is an open source firewall distribution based on the GNU/Linux operating system. Linux is the ideal choice for security systems; it is well proven, secure, highly configurable and freely available as open source code. SmoothWall includes a hardened subset of the GNU/Linux operating system, so there is no separate OS to install. Designed for ease of use, SmoothWall is configured via a web-based GUI, and requires absolutely no knowledge of Linux to install or use.

Find out more...