> Thunderbolt drive and High Sierra
If I upgrade to High Sierra, will my iMac still be compatible with my Promise Pegasus R4 RA ID, which contains my backups?
Yes, provided that you’re running current versions of the drive’s software, and that you update the drive’s firmware.
Before upgrading to High Sierra, visit the Promise support page at promise.
com/Support/downloadcenter. Select Legacy products, then model details. Download the Pegasus Series Utility for Mac and the Pegasus Series Driver for Mac, and install them.
It’s worth installing the driver, which is a kernel extension, before upgrading to High Sierra, since that version of the operating system handles third-party extensions differently.
With the new Pegasus Utility installed, you should be able to upgrade its firmware from within the app. If you have issues, download the firmware from the support page and install it using the Firmware Update command from the utility’s Admin menu, as detailed at bit.ly/firmprompeg.
Once your RAID drive is up to date, proceed with the High Sierra upgrade. When complete, it should be safe to leave Time Machine backups on, provided you don’t restart your iMac in Sierra. Doing so can wipe out the database Time Machine uses to decide what to back up. If you have a Thunderbolt RAID array and you’re thinking of upgrading your operating system, visit the manufacturer’s website and download the latest support software for your drive.