What is a Cloud?

The term “Cloud Computing” gets thrown around a lot these days, and while it does solve a lot of interesting problems, there is also a lot of confusion on what it really is, and I have not seen an easy to read, high level overview.

So, What is a Cloud?

While this seems like a simple question, usually its not easy to answer. This is because CLOUD means different things to different people, and it solves different problems for different customers. However, in its simplest form, a CLOUD is really just computing delivered as a service. Whether its Infrastructure as a Service (IAAS) like Amazon EC2, Platform as as Service (PAAS) like Google app engine, or Software as a Service (SAAS) like SalesForce.com;  all the end user cares about is, I need a resource to run a workload and I don’t care how or what happens under the covers, as long as I get the results I need.

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my Gnome3 experience

I have been avoiding updating to a newer version of Fedora for a while now, mainly because I have been very hesitant about the new Gnome3 desktop environment. Recently I took the Fedora 18 plunge and this post contains a couple of tricks and tips I learned along the way.

Gnome3-screen-shot

Atrix CM7

I have been really frustrated with my phone lately.  I’ve wanted to flash it with a non ATT ROM for while now however  I haven’t had the time and the Atrix’s locked boot loader has made this project a non-starter for me.  Not to mention that all the tools required to flash Android devices require windows boxes which is beyond me.

When the phone’s blue-tooth stopped working it was the last straw.  I had some spare time today and commandeered my girlfriends windows laptop for a couple hours to give it a try. There is a lot of info out there on how to do do this, however the instructions were still not very clear to me.  After reading a couple different xda forum posts and watching a couple of videos, I gave it a shot. Basically there are three things you need to do: 1)Unlock the boot-loader, 2) root the phone, 3) install a custom ROM.  This post contains a  steps I used to install CM7 on my ATT Motorola Atrix 4g. For more info check out this thread at XDA forums….

http://forum.xda-developers.com/showthread.php?t=1154600

However if you are still confused like I was, here are the three steps that need to be done and the order I did them in……

HUFFISLAND back up

After being down for a bout a year we are back up and running. I have imported some old tech post and have more to come, stay tuned…..

How to clean a LUN

RHEV 3.0 and earlier requires a clan LUN to create a new storage domain.  This is done intentionally so you do not overwrite existing data. However if you want to force RHEV to use a LUN with existing data you can wipe out the first 512 bytes of the lun to fool RHEV in to thinking the LUN is empty.

basically there are two steps………

1. Find the path to the LUN

Run the command “multipath -ll” on a host to see whether it “sees” the SAN luns or not, the output will look something like this if it “sees” the LUN:

mpath1 (3600d0230003228bc000339414edb8101) [size=100 GB][features=”0″][hwhandler=”0″]
\_ round-robin 0 [prio=1][active]
\_ 2:0:0:6 sdb 8:16 [active][ready]
\_ round-robin 0 [prio=1][enabled]
\_ 3:0:0:6 sdc 8:64 [active][ready]

If you do not see the LUN in the multipath output it means that the host can not access the LUN, ie its not presented correctly to the host. Check you SAN ACLS.  If you are using ISCSI  make sure you are logged in. see my post on ISCSI notes for more info.

2. “Clean” the LUN.  The LUN must be empty to add to the RHEV-M. You can use “dd” to wipe out the first 512 bytes of the lun to fool RHEV in to thinking the LUN is empty.

dd if=/dev/zero of=/dev/path/to/LUN bs=1024k count=10

doc:https://access.redhat.com/discussion/after-re-installation-rhev-lun-not-visible-rhevm-gui