Scad Programme

Archive for May, 2010

Repairing damaged partitions on is a risky business. Even if you use the best toolkit and are absolutely sure in what you are doing, you are still risking your files shall something go wrong. Changes made to the damaged partition are irreversible; it is just too easy to overwrite an important system structure that holds vital information about your disk, files and data. Bottom line: it’s good to backup before performing data recovery. But is this really the best way to do it?

There is a different approach to do data recovery that is even safer. No need to backup and restore during the recovery. Instead of making a backup copy of corrupted data, you can simply take a binary snapshot of the partition being repaired, and attempt the recovery with different settings as many times as you need on this snapshot instead of the actual disk.

SoftAmbulance Partition Doctor by http://softambulance.com/ is one of a few data recovery tools that allow recovering a virtual image of a damaged hard drive instead of repairing the hard drive directly. The data recovery tool lets you create a binary image of the damaged hard drive, and works with the binary image instead of the real thing. The binary image is a big file stored on another hard disk, CD, DVD or other media. The technology is similar to making an .iso image of a CD or DVD disc, only SoftAmbulance Partition Doctor extends it to partitions or even entire disks.

The hard drive copy may be virtual, but any data you save from it is for real. SoftAmbulance Partition Doctor can recover your files, documents and other data from the binary image and put it on a healthy media. After that, you can attempt fixing the damaged system structures of the corrupted hard drivewithout taking any risk at all. Any modifications will be performed on the virtual image.

Don’t rush the recovery. Don’t take the risk of losing or corrupting your data. Create a virtual snapshot of the hard drive being repaired, and work on that snapshot instead of accessing the corrupted hard drive. This procedure keeps your original data safe, and ensures the highest level of safety during the recovery process.

SoftAmbulance Partition Doctor recovers files from damaged and corrupted disks and partitions and fixes damaged hard drives. The disk recovery product supports all 32-bit versions of Windows, and recovers FAT and NTFS formatted hard disks, memory cards, CD and DVD media, and USB flash drives. The evaluation version is available for free at http://softambulance.com/

CCNA and CCNP candidates who have their own Cisco home labs often email me about an odd situation that occurs when they erase a switch’s configuration. Their startup configuration is gone, as they expect, but the VLAN and VTP information is still there!

Sounds strange, doesn’t it? Let’s look at an example. On SW1, we run show vlan brief and see in this abbreviated output that there are three additional vlans in use:

SW1#show vlan br

10 VLAN0010 active

20 VLAN0020 active

30 VLAN0030 active

We want to totally erase the router’s startup configuration, so we use the write erase command, confirm it, and reload without saving the running config:

SW1#write erase

Erasing the nvram filesystem will remove all configuration files! Continue?

[confirm]

[OK]

Erase of nvram: complete

00:06:00: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram

SW1#reload

System configuration has been modified. Save? [yes/no]: n

Proceed with reload? [confirm]

The router reloads, and after exiting setup mode, we run show vlan brief again. And even though the startup configuration was erased, the vlans are still there!

Switch#show vlan br

10 VLAN0010 active

20 VLAN0020 active

30 VLAN0030 active

The reason is that this vlan and VTP information is actually kept in the VLAN.DAT file in Flash memory, and the contents of Flash are kept on a reload. The file has to be deleted manually.

There’s a little trick to deleting this file. The switch will prompt you twice to ask if you really want to get rid of this file. Don’t type “y” or “yes”; just accept the defaults by hitting the return key. If you type “y”, the router attempts to delete a file named “y”, as shown here:

Switch#delete vlan.dat

Delete filename [vlan.dat]? y

Delete flash:y? [confirm]

%Error deleting flash:y (No such file or directory)

Switch#delete vlan.dat

Delete filename [vlan.dat]?

Delete flash:vlan.dat? [confirm]

Switch#

The best way to prepare for CCNA and CCNP exam success is by working on real Cisco equipment, and by performing lab tasks over and over. Repetition is the mother of skill, and by truly erasing your VLAN and VTP information by deleting the vlan.dat file from Flash, you’ll be building your Cisco skills to the point where your CCNA and CCNP exam success is a certainty.

If you are in the market for a computer, there are a number of factors to consider. Will it be used for your home, your office or perhaps even your home office combo? First off, you will need to set a budget for your new purchase before deciding whether to shop for notebook or desktop computers. Many offices use desktop computers because they are not intended to be moved around a lot. In addition, affordability often plays a large role in someone’s decision as to whether to purchase notebook or desktop computers.

While you are shopping around, it’s important to keep in mind some of the benefits that go along with owning different types of computers. To that end, this article provides five important reasons to purchase desktop computers.

- Desktop computers are typically much more affordable than notebook computers. With notebooks, you are paying more for the convenience of portability. For as little as $299.00, desktop computers can be purchased from one of the leading manufacturers and a notebook computer for as little as $499.00.
- Unlike notebook computers, replacing a keyboard, mouse, speakers or even a monitor does not require having your computer serviced by a professional repair shop. Because notebook computers have everything built in, including the aforementioned features, it is more difficult to replace a keyboard or monitor as opposed to desktop computers, which operate on external connections.

- In the event of an unlawful entry into your home, desktop computers are not as likely to be stolen because of their weight and bulk. Notebook computers, on the other hand, are small and portable. This, alone, makes them more appealing to a thief than desktop computers.

- Desktop computers are stationary by nature. Unlike a notebook computer, which can easily be moved from room to room, they are less likely to be dropped or broken because they are not moved as often.

- The vents on desktop computers are located on the back of the tower, which allows for proper ventilation that will help to prevent the computer from overheating. Notebook computers, on the other hand, feature only one vent on the back with the remaining underneath the base. If placed on a table, the air vents can become blocked and the computer may overheat. If prolonged use leads to overheating, damage may result.

When choosing from the many desktop computers on the market, always make sure that you purchase from a manufacturer who has experience in creating computers. Even though they are more affordable than notebooks, desktop computers are not cheap. With an investment that involves several hundred dollars, you will want to consider the length of time the manufacturer has been in business, their reputation with customers and their warranty.

Additionally, when choosing any system, including desktop computers, always look at the potential for future upgrading. As you grow, you will want your computer to grow with you and a part of that will include a slight upgrade from time to time. This is the only way to get the best use of your desktop computers and make sure that your investment is one that lasts for years to come.