Unable to use Encryption with Time Machine

I have been using the Time Machine Support on a Drobo 5D with Yosemite and earlier and would like to switch to encrypted backup which is supported according to this:

http://www.drobo.com/downloads/products/Feature-Brief-TM.pdf

I have Used Disable Backup to get rid of old TM partition and then enable backup to create a new one. When I select Encrypt backup option in Time Machine it is unable to initiate and says error preparing … and fails.

If I first format the partition (again) in Disk Utility I am able to setup as encrypted backup but I am worried this is messy with some of the low level Drobo magic since Disk Utility doesn’t really understand Drobo…

Encrypted Time Machine backups are not supported by Drobo volumes. See here.

There seems to be some contradiction between versions of Drobo’s own documentation. I get the impression that the one you referred to was written by the sales team (it’s well presented but full of hot air and sales-speak) while the one I’m referring to was written by engineering support (presentation-wise it’s a mess, but the facts are generally correct). I think your own experience demonstrates which department has it’s facts right. Do please contact Drobo support though and report their answer here.

[quote=“johnm, post:2, topic:141439”]There seems to be some contradiction between versions of Drobo’s own documentation.
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I’ve noticed that too. Drobo’s KB articles can be a bit of a mess presentation-wise (often badly worded, sometimes unclear for which system that was written, different fonts at times, different language, formatting all over the place, not very uniform throughout, different URL formats etc.), while their sales documentations are nicely written, but lacking depth. I with they’d spend some quality time to get their house in order and/or hire a technical writer.