No, this not about clicking on silly click bait articles.
Against everything I know, I decided to quickly make a few changes and clean up the file stores on a vmware cluster. I was thinking maybe an hour or so tops and I can enjoy the rest of my Saturday.
Using vmotion I moved a few virtual machines around to try balance everything nicely on the storage. Vmotion often leaves old directories lying around, so I decided to delete them to prevent confusion and keep things tidy for a change. The experienced sysadmins among you already know what’s coming.
I opened the datastore browser for vmstore1 and right clicked on the menu to delete directory proxy1 because the proxy1 virtual machine now lives on vmstore2. Suddenly I see a pop-up “Cannot delete file mail-flat.vmdk”. What? Yes! I clicked mail instead of proxy1 and when the system asked me I said yes I do want to delete it.
All the mail virtual machine’s file were gone except the virtual disk. No more virtual machine config or anything else. Yes the virtual machine was gone and would not start again. I deleted the dead machine from the vsphere inventory and decided to create a new one that will use the old virtual disk.
When I tried to select the existing disk while creating the new virtual machine, it didn’t appear in the selection. Not good at all, and the old saying, “When you are up to your ass in alligators it’s pretty easy to forget you originally wanted to drain the swamp”, comes to mind.
Panic slowly sets in. If I cannot recover the deleted virtual machine I get to spend 3 hours recovering the backup over the network. So I Google frantically and find a promising vmware knowledge base article
The article assumes that you still have your virtual machine config available but if you follow the instructions you will we able to recover the disk and use it in another virtual machine. Just remember this is an article that doesn’t say it out loud but implies “You screwed up, Here is a way that may fix it, Don’t blame us if it doesn’t work”.
Rather just restore your backup if you are not sure of your command line skills. You may even find that it doesn’t work out although you did everything correctly. If you have space available make a copy of your virtual disk file, if the steps in the article fail, you may still find another way to recover it on the net. I was lucky and had a fully running virtual machine in 15 minutes instead of 3 hours without any data loss. It could have been very,very different. more....
An ambitious new project is hoping to help clean the world’s oceans with a trash collector that is reportedly the longest floating structure in recorded world history.
Back in 2013 TrueActivist reported that a 19-year-old developed a plan to clean up the world’s oceans in just 5 years, removing 7,250,000 tons of plastic. However, last week, Boyan Slat (now 21), founder and CEO of The Ocean Cleanup, announced that this awesome project will be deployed in 2016.
Image Credit: theoceancleanup.com Continue reading
Hi I am Arnold Greyling from Johannesburg in South Africa. This is my peer review assignment for week 2 of the Introduction To Music Production
course at Coursera.org
. I will be discussing the Analog to Digital Conversion Process.
Analog to Digital conversion is converting a physical value (voltage) to a digital value that represents that physical value.
The following aspects of the Analog to Digital Conversion Process will be covered:
Representation of data in a computer and Word Length
Choosing the correct word length
Choosing your Sampling Frequency
The Analog to Digital Conversion Process is also known as sampling.
Representation of data in a computer
Data is always represented in a computer as a collection of binary bits. A bit represents a value of “0” or “1”. The bits are combined into bytes or words representing numeric values. A byte is normally understood as 8 bits. A word may have different lengths and the number of values that can be represented by a word is dependent on the number of bits in the word. The number of bits in the word is also known as word-length. The number of values is always the power of two of the word-length. See the table below for the number of values represented by often used word-lengths. more....
Hi I am Arnold Greyling from Johannesburg in South Africa. This is my peer review assignment for week 1 of the Introduction To Music Production
course at Coursera.org
. I will be showing you how to record an acoustic instrument in a typical home studio.
I will use the following equipment in this howto:
An acoustic guitar.
A Samson C2 condenser microphone.
A Steinberg UR22 USB audio interface.
A Macbook Pro Computer.
Garageband a Digital Audio Workstation (DAW) that Apple supplies free to Mac users.
This Howto will focus on setting up the equipment rather than the final recording and processing using the DAW. more....
It has been ages since I wrote anything on this blog, mostly due to too much procrastination. In 2009 I wrote Battery Centre needs the Battery University. The amount of hits this post gets is way more than anything else on the blog. Most of us deal with re-chargeable batteries every day so I though I will do my bi-yearly post again on batteries. Continue reading