The 2.1 version of Drobo S Firmware for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software lies within System Tools, more precisely Device Assistants. The actual developer of this free Mac application is Drobo. We recommend checking the downloaded files with any free antivirus.
From the developer:
The above download link is for the Drobo S, for other Drobo models see 'Related Links' below.
Drobo S Firmware ... The latest firmware updates for Drobo storage products. From the developer: To take advantage of the latest features, please update your Drobo products to the latest firmware or software versions. As always, we recommend following best practices which include backing up your data prior to installing the latest firmware.
You may want to check out more Mac applications, such as ToFi, iStar Composer or Portable Nvu, which might be similar to Drobo S Firmware.
Device Assistants
CD\DVD Software