Twitter Updates for 2011-12-14

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Twitter Updates for 2011-10-24

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Twitter Updates for 2011-10-19

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Cloning a thin disk in ESXi

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Found a great article that saved me a lot of time and headache when copying or “cloning” a .vmdk disk in VMWARE ESXi.

If you copy a vmdk from a ESXi system via ‘cp’ or anything similar, your so called sparse-vmdk, will blow up to the maximum size which was defined.
For example, a VM with a 25G partition shows up with 25G but needs only the space which consumes the data you really have.

The parameter ‘-s’ in the command ‘ls’ presents the really needed space.

 ls –slh *.vmdk
140K -rw------- 1 root root 8,0G  3. Aug 14:20 bac-test-flat.vmdk
4,0K -rw------- 1 root root  424  3. Aug 14:22 bac-test.vmdk

The vmdk was freshly created and no operating system was installed. It consumes only 140k instead of the defined 8G.

So far so good, but a copy with ‘cp’ will replace the null-pointer in this file with real zeros. The result is a 8G consuming file with only zeros in it and the storage efficiency is gone.

For copying vmdk files, there is a tool called ‘vmkfstools’ available on the ESXi server.

vmkfstools -i "source.vmdk" -d thin "destination.vmdk"

There should be no snapshot and source and destination are the meta vmdk files. e.g. vmname.vmdk (not flat or delta).

‘thin’ is the secret of keeping the null-pointer in the flat file.
The tool also reverts a vmdk which was blown up, back into a thin file!

For an easier usage i wrote a tiny script to copy like it is with ‘cp’:

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#!/bin/bash
if [ -n "$1" ] || [ -n "$2" ]; then
SRC="$1"
DST="$2"
else
echo "Error: Usage $0 [source] [destination]"
echo "Use only vmdk-meta files! no flat or delta allowed!"
echo " "
exit
fi
vmkfstools -i "$1" -d thin "$2"

create a script called ‘vmcp’,
save it in /usr/bin
and set execution rights (chmod +x /usr/bin/vmcp)

Now you can copy with

 vmcp source.vmdk destination.vmdk

This worked great!

Google SSL

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I noticed today that you can do end to end encryption when searching Google. From Google’s website:

Features: SSL Search
Print

With Google search over SSL, you can have an end-to-end encrypted search solution between your computer and Google. This secured channel helps protect your search terms and your search results pages from being intercepted by a third party. This provides you with a more secure and private search experience.

To use search over SSL, visit https://encrypted.google.com New window icon each time you perform a search. Note that only Google web search is available over SSL, so other search products like Google Images and Google Maps are not currently available over SSL. When you’re searching over SSL, these properties may not appear in the left panel.
What is SSL?
SSL (Secure Sockets Layer) is a protocol that helps provide secure Internet communications for services like web browsing, e-mail, instant messaging, and other data transfers. When you search over SSL, your search queries and search traffic are encrypted so they can’t be read by any intermediary party such as employers and internet service providers (ISPs).
What can I expect from search over SSL?
Here’s how searching over SSL is different from regular Google search:

* SSL encrypts the communication channel between Google and a searcher’s computer. When search traffic is encrypted, it can’t be read by third parties trying to access the connection between a searcher’s computer and Google’s servers. Note that the SSL protocol does have some limitations — more details are below.
* As another layer of privacy, SSL search turns off a browser’s referrers New window icon. Web browsers typically turn off referrers when going from HTTPS to HTTP mode to provide extra privacy. By clicking on a search result that takes you to an HTTP site, you could disable any customizations that the website provides based on the referrer information.
* At this time, search over SSL is supported only on Google web search. We will continue to work to support other products like Images and Maps. All features that are not supported have been removed from the left panel and the row of links at the top. You’ll continue to see integrated results like images and maps, and clicking those results will take you out of encrypted search mode.
* Your Google experience using SSL search might be slightly slower than you’re used to because your computer needs to first establish a secure connection with Google.

Note that SSL search does not reduce the data that Google receives and logs when you search, or change the listing of these terms in your Web History New window icon.
Information for school network administrators

*
How will SSL search affect our content filtering services?

When students search using https://encrypted.google.com, their searches will bypass any content filters that are in place on your network. If this is problematic for your school, you can block https://encrypted.google.com. When students continue to search using http://www.google.com, your content filtering will work as it always has in the past.

If your students try searching via the https://www.google.com homepage, they will be redirected to https://encrypted.google.com and will not be able to perform encrypted searches to bypass content filters.
*
If I block access to https://www.encrypted.google.com, will I block access to all of Google’s authenticated services (like Google Apps for Education)?

No; logins for Google Apps for Education New window icon and our other authenticated services are currently hosted at https://www.google.com. As long as you allow access to https://www.google.com, your organization should still be able to access all of our other services.

Does SSL provide complete security?
While SSL helps prevent intermediary parties, such as ISPs, from knowing the exact search that you typed, they could still know which websites you visit once you click on the search results. For example, when you search over SSL for [ flowers ], Google encrypts the query “flowers” and the results that Google returns. But when you click on a search result, including results like images and maps, you could be exiting the encrypted mode if the destination link is not on https://.

If your computer is infected with malware or a keylogger, a third party might still be able to see the queries that you typed. We recommend that everyone learns how to prevent and remove malware.

Remember that only Google web search supports search over SSL, so searching Google Images, for example, will not be encrypted.
Technical discussion of SSL protocol-level limitations

While SSL is a clear privacy and security benefit, we are aware of some technical limitations to SSL at the protocol level that are not specific to Google’s implementation:

* A determined, skilled malicious party could potentially interpose himself into the network traffic and present a spoofed certificate to the user. In many cases, this will result in a certificate warning to the user. If you see a certificate warning, the protection may not hold.
* An adversary with the ability to install root certificates on the machine could potentially interpose himself into the network traffic without any warnings appearing.
* A highly capable source may be in a position to sign certificates with a standard, pre-installed certificate authority (CA), which again would allow intercept without any apparent warnings to the user.
* Even if all web searching occurs over SSL, a passive traffic listener may still be able to observe DNS look-ups.

How can I confirm whether I’m on a secure connection?

Check to see that the URL you’re on starts with https:// instead of http://. Most browsers provide a visual confirmation (such as an icon of a lock) in the address bar or in the status bar at the bottom of the page. On Google SSL search, you’ll also see a special Google SSL logo with a lock icon. In addition to this logo, be sure to also check the https:// text in the address bar and any browser lock icons.

When you perform a search on https://encrypted.google.com New window icon, you might see a warning if a page has some non-secure components: depending on your browser settings, you might see the lock icon turn into a warning sign, a pop-up message, or some other form of alert. This issue is often referred to as a “mixed mode error.”

Since this is a beta feature, there might be some rare cases in search over SSL that generate a mixed mode error. We’re working to prevent such errors, and you can help if you report any errors New window icon through our Help Forum.

Exchange 2007 Import SSL Certificate

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Well written article on how to import an SSL certificate into Exchange 2007, IIS , SMTP, POP3, IMAP etc.

SpiderOak Online Backup

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There are many backup services available on the web now. Mozy and Carbonite are two of the most popular. I came across a new player called SpiderOak. I have been running it for about a week now and I must say I am very impressed. 2gig of free storage with the ability to add more and share. Check it out when you get a chance.
SpiderOak.com

2010 Best Gadgets

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If you are into gadgets like I am, head on over to gizmodo for this years best! Some of them make sense, and some don’t.

Ipad vs Blackberry Playbook

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Now that a bunch of different players are in the market, the question has to be asked; “Which tablet system is best?” I use the term “system” because I believe it is more than just hardware that defines the tablet market. If the platform has no applications, then it will be more difficult for a company to find uses for the tablet in their business. Apple has the apps and the hardware. They have backwards compatibility and great way of rolling out updates.
Just a thought.

Blackberry Playbook
Apple iPad

Clearing your Windows Printer Queue

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Ever had problems with your Windows printers suddenly disappearing? Generally this has to do with a print job that has become corrupted. Follow these directions and you should be up and running in no time!

If you have a long list of hung print jobs in Windows 7 or Vista, you can clear the print queue easily by using these steps.

1. Click Start.

2. Type Command.

3. Right-click Command Prompt and select Run as administrator.

4. Type net stop spooler then press Enter.

5. Type del %systemroot%\System32\spool\printers\* /Q then press Enter.

6. Type net start spooler then press Enter.

The print queue on your Windows 7/Vista system should now be cleared. Type exit and press Enter to exit the command window.

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