macOS Catalina warning: Don't upgrade if you rely on a Drobo 8D

Here's a quick note of caution. Your Drobo drive array may be unstable if you upgrade to Catalina. Whenever there's the potential for data loss, we have to advise you to just say no.

Why Catalina is one of macOS' most impressive updates Even in its current beta form, Catalina looks like one of the most impressive updates that macOS has received in recent years. Read more:

Yesterday, ZDNet's storage guru Robin Harris reported that he went ahead and upgraded his Mac to macOS Catalina as soon as it was released. As Robin told us, it was a mistake.

He described how many of his 300+ apps were not yet compatible with Catalina. That's no surprise. Every big OS upgrade causes some incompatibility. However, the Catalina upgrade has bigger potential to upset because Apple has finally eliminated support for 32-bit apps.

So far, most of the coverage about Catalina has been about software incompatibilities. But now, we've got a bigger warning for you. Some storage may be compromised.

Late last year, I gave you a look at Drobo's latest direct-attached storage array, the Drobo 8D. What made the 8D stand out was that it was Drobo's first Thunderbolt 3-based device. I've been using it all year and am very satisfied with its performance.

But now, Drobo has issued a warning. Buried in the company's Upgrade Guide for macOS Catalina, where it discusses how to properly backup and then upgrade most Drobo storage arrays, was this warning:

We have noticed an issue with connectivity over Thunderbolt 3 on macOS Catalina 10.15 and are actively working with Apple. For now, we recommend 5D3 customers to use the USB C port, and for Drobo 8D customers to wait on upgrading.

The 5D3 comes with one USB C port and two Thunderbolt 3 ports. While not necessarily ideal because USB C is slower than Thunderbolt 3, switching cables from Thunderbolt 3 to USB C is not a big hassle.

On the other hand, the wonderfully beefy Drobo 8D only has Thunderbolt 3 ports. Since Drobo has "noticed an issue with connectivity," there's no real way to re-route the 8D to a USB C port. That's why Drobo is recommending you "wait on upgrading."

That's it for this article. I rely on the 8D Drobo sent me, so I'm not going to upgrade to Catalina for a while. Hopefully, Drobo will release an upgrade to the 8D (and their other devices with Thunderbolt 3 support) that overcomes whatever "issue with connectivity" it's having before anyone loses any data.

Have you upgraded to Catalina yet? What challenges or successes have you had? Let us know in the comments below. I always wait months before I do any upgrades to mission-critical systems. I probably won't brave Catalina until the new year. What about you?

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