Mirroring two Drobo Pros?

We have a Drobo Pro we are using on our main production file server running off of a Apple Xserve.

Our company has been talking about offsite mirroring of data and is looking to install another DroboPro at a Colocation centre near us.

Our first though is to just rsync ( http://en.wikipedia.org/wiki/Rsync ) the two devices nightly. I was wondering if anyone had a better way to mirroring two DroboPros? Or if the Drobo developers have a better solution?

Drobo Dashboard includes the DroboCopy utility. This will duplicate file from one directory to another. This utility only works on directories - so you could need to have the filesystems for both DroboPros accessible on the one computer. Either directly via iSCSI or a mounted network share.

Personally I think rsync is the way to go.
Rsync has a very useful feature in the --link-dest option which hard-links files that have not changed. You should read up on it if you are not familiar with how it works. This will let you do incremental backups - so rather than a straight mirror you have a proper backup solution with as many days worth of backups as you require using a minimal amount of space.
Rsync can also run over SSH if you require encryption when transmitting the data to your remote location.

Disclaimer: I don’t work for R1Soft or related to this company in any ways such as reselling their software or marketing.
Just my two cents esepcially for DroboPro users like us who have the genuinely need to protect our business-critical digital asset on the DroboPro and block-level CDP is definitely the way to go. There are over a dozen of vendors develop block-level, disk-based & applicaiton aware w/ full BMR (Bare Metal Recovery) & Replication capabily, AppAssure Replay4, InMage Scout, BakBone NetVault, Microsoft DPM, StarWind Software, Vizioncore vRangerPro etc.