Tales from the past – Disaster Recovery testing

A long time ago in a datacenter far, far away….

Turmoil has engulfed the IT landscape. Within the newly formed digital universe,
corporate empires are becoming more and more
dependent on their digital data and computer systems.
To avoid downtime when getting hit by an evil strike, the corporations are
starting to build disaster recovery capabilities in their operational architectures.

While the congress of the Republic endlessly debates whether
the high cost of decent recovery methods is justified,
the Supreme CIO Chancellor has secretly dispatched a Jedi Apprentice,
one of the guardians of reliability and availability,
to validate existing recovery plans…

Another story from my days as UNIX engineer in the late nineties. I obfuscated all company or people names to protect their reputation or disclose sensitive information, but former colleagues might recognize parts of the stories or maybe everything. Also, some of it is a long time ago and I cannot be sure all I say is factually correct. The human memory is notoriously unreliable.

In those days, our company was still relying on tape backup as the only Disaster Recovery (DR) strategy. The main datacenter had a bunch of large tape silos, where, on a daily basis, trays of tapes were unloaded, packed and labeled in a small but strong suitcase, and sent to an off-site location (Pickup Truck Access Method) so the invaluable data could be salvaged in case our entire datacenter would go up in flames.

Big Ideas; Big Tech: Continuous Operations for Oracle RAC with EMC VPLEX

Here’s an EMC video on Youtube about Oracle RAC with EMC VPLEX. Very nice, check it out!

http://www.youtube.com/watch?v=DRtl6dU2P_E

Oracle and Data Integrity: Data in, Garbage Out?

A trivial question:

What is the basic function of a storage system?
I would say, the trivial function of a storage system is to store digital data and getting it back when you need it.

To be specific:
get the data back exactly the way you stored it.

You would probably say “Duh, of course!”

A storage system (as simple as a hard disk or as sophisticated as an EMC VMAX) is supposed to store data and give it back unmodified. But recent research shows that simple disk drives are not as reliable as you might think. Enough material is available that explains why and how often disk drives fail to return the correct information, often without any error as if the corrupted data is perfectly valid. See below for more references to this issue.

Data Guard or Storage based replication?

A comparison between Oracle (Active) Data Guard and EMC replication for disaster recovery purposes

This is an article I wrote a while ago for customers’ Database Administrators (DBAs) and application managers, that helps them in selecting the right Disaster Recovery tools for their business applications.
It is slightly modified to update new insights and to make it more readable on the web.

Desktop security: Application data got blurred

In the old days, when I started messing around with computers for fun as a young geek guy, computer security was pretty simple.

Amiga 2000

In those times we were using 8 or 16-bit PC’s with MS-DOS (for the poor guys) or, for the wealthy like myself, Commodore Amiga or comparable computers with real magic inside (who else around 1988 had 4-channel 8-bit stereo sound, 4096 colors, coprocessors for audio and graphics, true multitasking, a mouse-driven GUI handling multiple screens and windows, capable or running a word processor, graphics editor, sound tracker and some other stuff, all at the same time in 512 KB RAM?)