Apple recently released its latest macOS known as High Sierra (version 10.13). The technology firm continues its fairly recent practice of offering its latest OS upgrade as a free download from the App Store. While you may be tempted to take immediate action and initiate the upgrade process without much forethought, you need to be aware of the risks involved and what steps you should take first, especially if things don’t work out as expected and you need to restore the current OS that you’re running.
What Color Is Your Parachute?
Imagine you are riding in an airplane at 12,000 feet as part of a search-and-rescue team and are tasked to pick up injured survivors who are trapped in a deep ravine. You have been given orders to jump from the craft when you reach their last known location. Obviously, you wouldn’t exit the plane without being properly fitted with a parachute.
Several years ago, in response to changes in the marketplace and technological advances that have enabled broadband usage to become much more widespread, Apple eliminated the macOS installation disks that it previously bundled with each new Mac. In that bygone era, one fallback option available to Mac users was the ability to use their original disks to reinstall clean copies of their system software and applications on their computers, which were typically equipped with SuperDrives. Being totally dependent upon Apple’s servers for system software could result in an unpleasant surprise if you become dissatisfied with a macOS and later learn that you cannot download and install the same version that you were using before you upgraded.
With the Sep. 2017 release of High Sierra, Apple introduced a new file system (APFS) that is destined to replace the HFS+ format that has been the standard for years. The migration to APFS will automatically take place on High Sierra upgrades of Macs equipped with built-in flash memory drives, unless you run a special Unix script that disables the changeover. Initially, APFS will not be supported on iMacs and Mac minis that are equipped with Fusion Drives. Instructions for restoring the HFS+ format after your macOS has been converted to APFS are described in an Apple document entitled, “Preparing your Fusion Drive Mac for the macOS High Sierra install.”
Why You Should Be Concerned About Apple’s New File System
After all, my personal data is safe, right? I regularly back up my email and photos to iCloud, and save essential documents on my flash drive. What can possibly go wrong?
There’s a time-honored axiom in the tech world to avoid installing software applications with a version number of 1.0. Wait until the developer releases a software update that addresses the bugs that invariably come to light after the program has been in use for a while.
Think of APFS as version 1.0 technology. Because APFS is brand new to the market, most Mac users don’t have the experience or advantage of knowing how they will be affected by the change.
For example, do you self-diagnose your Mac using commercial software applications such as Disk Warrior or TechTool Pro? Is your version certified to run under High Sierra? If you don’t keep such programs on hand, do you occasionally hire a consultant to troubleshoot your Mac? Do you know whether your consultant has the necessary tools and expertise to work on a High Sierra system that’s installed on an APFS flash drive?
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