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Test your backup system

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How often do you test your organization's backups? Have you run into a problem like Mike Talon described? Tell us what you think about testing a backup system, as featured in this week's Disaster Recovery e-newsletter.

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Testing is neither easy nor simple!

by draco vulgaris In reply to Test your backup system

Restoring a few files on an NT server is not difficult. A similar system to use as a test platform is not unreasonably expensive. You can teach the receptionist the difference between a cleaning tape and a data tape. You can even check log files to see if a backup was actually done.

Now try a case where you have a 200GB Oracle Database running on an enterprise class "mini" computer. In my case it's Alphas and VMS but a Unix system would offer similar problems. You can't use the production system for your testing. The hardware is expensive! You can't just restore a few files. You don't know if it works until you restore the whole database from tape and then do a "media recovery" to bring it up-to-date from the archived redo logs.If the database will start and the application(s) will run, you are a success. Nothing less will do!

I test once a year during our Disaster Recovery test. In the best of circmstances it's an all day exercise.

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You're right!

by MikeTalonNYC In reply to Testing is neither easy n ...

If you'll note, in the article I did point out that larger system testing would be more complex, but just as vital.

Many companies can only do testing once a year due to expense, but they still do that testing.

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Additional Tips for Testing

by ChipN In reply to Test your backup system

1. Extract the data on a DIFFERENT device (tape, CD, whatever) than it was created on. A big part of validation is making sure that another device can read the media.

2. Checksum / fingerprint (using a tool like "sum" or "MD5" files - at least critical ones). If there is ever a problem this will help you determine whether the data was bad going on the back or coming off. This implies that the checksums reside on separate media!

3. Perform a daily random check of at least one file from a backup set (again, using a different device). The checksum data is a quick way to validate that the data is as good as the original data. This implies that the original data is tested on a periodic basis!

We have found this invaluable for general data protection, as well as DR. One of the largest sites that I implemented this (a large insurance company) had an operator spend 3-4 hours a day performing these validations in conjunction with other activities. It was a hard sell at first tohis manager, but after that their DR media always worked.

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The more they stay the same

by SilverWolf In reply to Test your backup system

While doing security in the early 70's; at a major midwest grocery warehouse headquarters that ran one of the country's best IT depts. to handle their chain; an incoming semi truck hit a power pole at the entrance to the facility taking out the power and of course the computer system. This company had massive battery and generator backups for their computers, but they failed to kick in as they were supposed to do and they lost all of their data. It took them almost 3 months with full staaff working round the clock and living on site to get back to toatally operational.

This is because no one did a full operational test of that backup system. The more thhings change.....

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my experience in DR

by milis In reply to Test your backup system

several months ago.. i my system crashed! but lucky me, i always test my backup (i done it daily) once a month and i always doing monthly backup which i kept on a diffrent location (safe deposit box).

and after the system crashed i was able to retrieve ALL the data, including my Exchange server.

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Testing tape restore

by sbern227 In reply to Test your backup system

Testing applies to smaller businesses, not just large databases. I recommend a test restore just to be sure the clients know how to use their software. It is a "retraining" exercise as well as test.

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Testing applies to ALL businesses

by MikeTalonNYC In reply to Testing tape restore

Big or small, any business must test the validity of backed-up data. Not doing so ensures that you will lose data sooner or later, regardless of the size of your organization.

Mike Talon

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