tue - backup scare posted: Tue 2018-03-20 07:56:49 tags: tech
Mental Floss: What If? 19 alternate histories imagining a very different world

Art of Manliness: How to Make Small Talk with Strangers
Why would anyone want to do THAT? Well, turns out it's a highly rewarding pastime, because of sciencey reasons.

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I discovered something scary about my backup set this morning: instead of encrypted zips of each file, there were EMPTY zips. 1Kb placeholders with no content (other than the zip header internals, presumably). I turned off the "Volume Shadow Copy" and "Use Archive Attribute" flags and set the backup type to Full (was: Incremental). It STILL did not overwrite many of the empty files. I moved the backup set to force a full fresh backup job; still all empty placeholder files.

I turned off encryption. Now it copied all specified files as intended. I wouldn't entrust unencrypted copies to a cloud backup repository, so I had a problem to solve. The ideal solution retains individual file identity so you're only syncing changed files to the cloud, not a monolithic multi-GB container. I speculated that Cobian's crypto engine might depend on the compression engine, so I enabled compression and re-enabled crypto. This seemed to work as desired, so I switched back to type Incremental and re-enabled archive bit logic. Tested file restoration on a few file types, and was satisfied it worked as intended.

So my conclusion is Cobian's encryption DEPENDS ON compression. Compression slows down the process some, but on a job scheduled for after-hours it's not much of a concern.

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Processed all the Facebook saves (emergency kit suggestions from The Fifth Columnn, car tire shopping tips from Consumer Reports, my cousin Laura's recommendation of Fanny Hill's 1972 album, Catrim's red beans + rice recipe, much more)