Bandwidth of a Station Wagon

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On March 12, 2007, Sun’s CEO told an audience it was faster to send a petabyte of data from San Francisco to Hong Kong on a slow boat than by wire.  People find that statement incomprehensible.  Many vendors of disk and de-duplication solutions rely upon this lack of knowledge and seldom bother to talk to customers about the recovery portion of backup and recovery.

As long as a major disaster is averted, no one gets hurt.  However, betting the data center farm you’ll never have to exercise a large scale recovery is generally not prudent.  It’s like playing lotto in reverse.  If you hit the “winning” ticket you’ll pay dearly. 

Unfortunately, customers who believe that simple data transmission by wire in small, de-duplicated quantities is all they’ll need for DR are doing just that… betting their business they’ll never have a large scale disaster from which to recover.  How does one insure against such calamity?

Asking two questions of your storage provider can help determine whether you may find yourself in a tight recovery spot.  If you ask how long it will take to move the data over a given transmission line and how expensive it will be to do so, you can save yourself a lot of potential heartburn.  Knowing the answers to these questions is important for backup, but can be deadly serious on the recovery side.

For example, if you’re transferring a whopping 50 GB of data over a T-1 line you can do so fairly inexpensively.  The cost may be only a few hundred dollars a month.  Unfortunately, it will also take you over 77 hours every time you choose to do so with a T-1.  Alternatively, you could pay for an OC-3 line and move 50 GB in about 42 minutes.  The trouble is, it could cost you several thousand dollars per month depending on the service provider.  In both cases, the truth of the situation can radically change your thoughts on your backup and recovery strategy – particularly when it comes to fast recovery.

As for that petabyte we talked about earlier?  Well, if you want to pay gigantic sums of money per month you too can access an OC-192 line and move your petabyte to China in just over 9.5 days – or slightly less time than it takes for that slow boat to get there.  If done over a T-1, however, no one reading this will live long enough to see that transmission complete (176.2 years).

The next time you consider backup, and more importantly recovery “over a wire”, find out how long and how much it will cost you to move your data to the backup site.  More importantly, find out what those metrics will be if you have to get your data back in a hurry!  You may just learn that the old adage, “Never underestimate the bandwidth of a station wagon full of tapes!” is not only true but also the right solution for you.