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Hyper-Threading is a technology included by Intel first in their Netburst line of parts. Hyper-Threaded processors present their individual processing cores to the system as if they are two processing cores. To use Intel’s parlance, that means that each physical core appears in the operating system as two logical cores. While the OS can distinguish between a system that has two logical cores (i.e. a single physical core with Hyper-Threading enabled) and two physical cores, applications cannot. It is up the the OS’s scheduler to choose if it wishes to use logical cores in the same manner as physical cores

There are times where I run a command that I needed to only need it again at a later time.  Most of the time I document my steps, but there are those time where I just do things in the heat of the moment to get what I need done.  So what can one do?  Well when you’re in your command shell and looking for that command you once knew, all you need to do is simply type:  history

History will return a log of all the commands you have typed.  So when in doubt, look back at your history and bring back those lost memories.  Good luck

With a recent need to update and configure switches at the office.  I used a few simple steps to make this all happen.   These steps require you setup a closed network with a DHCP Server and TFTP Server and connect all switches to this network.

TFTP Software Update to ProCurve Switch

Connect to switch via serial cable to access to the console.  Here you can use the CLI to send instructions to the switch.

Execute the copy command as shown:

# copy tftp flash <ip of the tftp server> <software filename ex. W_14_28.swi>

You will see the following response:  The primary OS image will be deleted.  Continue [y/n]? Y

This will update the primary software version.    The secondary can be update at a later time.

TFTP Configuration Settings to ProCurve Switch

Connect to switch via serial cable to access to the console.  Here you can use the CLI to send instructions to the switch.

To take a backup of the configuration file to a TFTP server type:

copy startup-config tftp <ip of the tftp server> <filename>

To restore the switch’s configuration file, you can use TFTP for the upload:

copy tftp startup-config <ip of the tftp server> <filename>

Note: that the switch will reboot whenever you upload the configuration file from a TFTP server

Recently I had a need to install Windows 7 on a computer and I was out of DVD media to use. The only media I had was a 8GB USB Thumb drive. I have done this many of time in Windows itself with various of tools and eve manually. Now I do it in Linux also.

Here is a small list of items one would need:

1. Windows 7 ISO Media
2. 4GB or larger USB Pen Drive
3. And Linux Install with root access (sudo, will work fine)

Open up a terminal and location the device that your USB drive is mounted to.

In my situation I had my USB Pen drive mounted at the following location /media/usb, the device was location at the following location /dev/sdb1

I first unmounted the drive using the following command:

sudo umount /dev/sdb1

I then changed directories until I was in the path of my Windows 7 .ISO image. This is not necessary; I do this out of habit. I then use the ‘dd’ command to copy the .ISO image to the USB Device (USB Pen Drive). Example: dd if=windows7.iso of=/dev/sdb1

After a short while the image is fully copied to the USB Pen Drive and you can then boot from this device to begin the Windows 7 Install

The shred command can be used for destroy files so that their contents are very difficult or even impossible to recover. The shred command accomplishes its destruction by repeatedly overwriting files with data patters designed to do maximum damage. Even the use of high-sensitivity data recovery methods and equipment make it difficult to recover files that have been shredded.

In Linux I often find myself using the ‘rm’ command to delete files, however this does not destroy the data it just destroys the index which lists the location of the file and makes the data blocks available for reuse. In short, a delete of the file does not remove the files and there are utilities that can read the blocks and get the data back. Such a tool is ‘testdisk’ which can image all the blogs on disk and recover deleted files.

Using ‘shred’

shred’s syntax is: shred [option(s) file(s) or device(s)

When using ‘shred’ without any options it will overwrite any file or device 25 times, which is generally sufficient to remove all traces of data. A device can be a partition or even an entire HDD, USB Key, etc.

Example: I would like to use shred to delete a file(s) and cause full destruction. By typing the following ‘shred filename1′ this will shred the file with the default setting of 25 times.

The default number of overwriting can be changed by using the -n option followed by an integer representing the desired number

The most reliable way to destroy data is to ‘shred’ an entire partition. For example, the following would destroy data on a unmounted SD Card: shred /dev/mmcblk0 thats if the device is plunged into this location. The location may be different so please be sure to use the correct one for your situation.

End Notes:

Even after overwriting data, it is possible for someone to take the HDD or other storage device to a specialized data recovery laboratory and use highly sensitive (and expensive) equipment to search for the faint traces of the original data, which can be relatively easy to detect if it has been overwritten only one or a few times. Thus, the best way to remove data on a HDD irretrievably is to physically destroy the media on which it is stored, such as by opening the drive and rubbing the individual platters with sandpaper. However, as this can be tedious, shred provides a alternative that can be almost as good but which requires much less effort and cost.

Google Voice, the popular and often controversial VoIP, voicemail, and messaging service from Mountain View search giant Google is now open for anyone in the U.S. to use. Previously, you could only open a Google Voice account if you received an invitation from a user already participating in the program.

Quote from the people at Google:

“We’re proud of the progress we’ve made with Google Voice over the last few years, and we’re still just scratching the surface of what’s possible when you combine your regular phone service with the latest web technology. It’s even more amazing to think about how far communication has come over the last couple hundred years”

To sign up for Google Voice, click here

Here are some things you can do to get started with Google Voice:

1. Read transcriptions of voicemails. Watch a video »
2. Customize which phones ring. Watch a video »
3. Personalize greetings for different callers. Watch a video »
4. Make cheap international calls. Watch a video »
5. Forward SMS to email. Watch a video »
6. Share voicemails with friends. Watch a video »
7. Block unwanted callers. Watch a video »
8. Screen callers before answering. Watch a video »
9. Access the mobile app on your phone. Watch a video »
10. Conference call with co-workers. Watch a video »

Today, the newest version of popular open source blogging software WordPress was released. Version 3.0, also known as “Thelonious,” has undergone a significant number of improvements, such as the inclusion of new standard APIs that let theme developers easily implement new backgrounds, headers, menus, custom posts, and more.

All of the new APIs are shown off in the new default theme called “Twenty Ten.”

For users, support for URL shorteners has been included in WordPress 3.0, so you can tie your blog to your favorite link shortening service, and generate short links from within the WordPress dashboard.

In total, there are more than 1,200 bug fixes and feature enhancements in this version of WordPress. If you’re a user of the software, simply go to Tools>Update in your dashboard to download and install the new version either automatically or manually.

I fist must state that these steps I am about to provide are to be used by those of us whom are neurotic about files stored on the file system.  While there are some good security reasons one may want to do this; I do what I am going to describe because I feel they clutter up my drive and dislike seeing or even knowing they are there.

My default windows (Win7 in my case) generation a file called thumbs.db in the folder that I am working in. The file thumbs.db is a thumbnail cache, used to store a small (thumbnail) image for Windows Explorer thumbnail view.  The idea is to speed up the display of images as the smaller image does not need to be recalculated (regenerated) every time the use views the contents of a folder.

So what do I do about it?  At first I use to delete them; that only makes me happy for that moment, as they come back like some kid with acne who pops one pimple to later show up again.

By using the Local Group Policy Editor I have found a better way to keep these guys /or gals from coming back.  You can start the Local Group Policy Editor by typing gpedit.msc in the search or run text box.

The Editor will open to the top-level Local Computer Policy, so you will have to expand the User Configuration item in the left-side pane of the Editor window.  Drill down through Administrative Templates, then Windows Components, and click on the Windows Explorer item.  Near the top of the list in the right-hand pane of the Editor window you will find the setting “Turn off the caching of thumbnails in hidden thumbs.db files”

To edit this policy setting, either double-click on the title of the policy or click the link titled “Edit Policy Setting” to the left of the setting list after you select the policy.  Check the “Enabled” button and click OK

Close the Local Group Policy Editor.  You may want to unhide all hidden file sand system files and do a search for the files and delete them.  And now I can be happy knowing they are gone.

For some time I have always used tools such as scp sftp to copy files between Linux based systems. Until the growing need to have this process simplified.  I recently fell in love with Linux all over again with the new release of Ubuntu.  I always had known it was possible but never had the direct need to mount ssh file systems remotely.  This is where some Google searching and SSHFS and FUSE came into play on my home systems.

So what are some things I found out?  Well for one; as long as I have SSH access to a remote system I can use SSHGS to mount and use the remote directories as if they were on my local system.  SSHGS require no special software on the remote host so this is good in a hosted situation where you have no control over what gets installed.

This is where I give you the * filler * info on SSHFS.

SSHFS is built upon the FUSE user-space file-system framework project.  FUSE allows user-space software; in my case SSH to present a file-system that is virtually interfaced to the end use.  SSHFS connect to the remote system and does all the necessary operations to provide the look and feel of a regular file-system.

So now what?

First we need to start off by installing sshfs if not already installed.  I am using Ubuntu like I had mentioned above so by typing sudo apt-get install sshfs that installs all I need and supporting requirement.

The fun part.

Create a local directory where you want the files mounted.  This process is similar to mount smb shares from another system.  In my example I will be mounting the directory /home on the remote server to a local path on my system:

“sudo mkdir /mnt/remotehome1”

“sudo sshfs jermsmit.com:/home /mnt/remotehome1

You can also change the owner of the new directory by typing chown ‘yourusername’ /mnt/remotehome1

Please note that the /mnt/remotehome1 directory must exist and be owned by you, so keep in mind when you make (for example) /mnt/remotehome1/ you should assign permissions to your user so that you may access it.

To unmounts the directory, you can use the command fusermount –u.  Example fusermount –u /mnt/remotehome1.  If you get a message about the path being in use make sure that you have change directory out of this path and try again.

That’s about it.  Very clean and simple, and next time I hope to write about setting this up in such a way its auto mounted on startup (aka persistent), but for now this gets the job done.

If you are using SSH to tunnel your web traffic, to keep your information private, you might be vulnerable to a DNS man-in-the-middle attack.  If your DNS requests aren’t tunneled, the operator of the hostile (or locked down) network can still see where you are navigating to on the web when your client makes DNS requests to resolve hostnames to IP addresses.
For these reasons (and for many others), it’s a good idea to tunnel DNS through your SSH tunnel too.  This can be done very easily in Firefox.

In the Firefox URL address bar, enter “about:config“.
In the Filter text field, enter “network.proxy.socks_remote_dns“.
Double-click “network.proxy.socks_remote_dns” to set the value to true.