Mike's picture by Mike | March 30, 2023

We're on the eve of World Backup Day – March 31st (because you're an April Fool if you didn't back up on March 31), so now is a great time to revisit some Backup Best Practices. If you're already using CCC for your backups, you've got a great leg up! If you haven't given it a whirl yet, today is a great day to try it out.

We all want our backups to protect our data; that's the obvious reason for making them. But we also want them to be reliable, easy to use, fast, and generally out of sight. It's like that furnace in your attic – you want to know that it's working, but you don't want to have to think about it every day. Once a year, though, maybe you should give it some attention to make sure the condensate isn't going to start leaking through the ceiling. (Yes, that's a very specific analogy 😉)

Here are a few suggestions to get your backup strategy in top-shape.

Create a backup on directly-attached storage

NAS and cloud-based backups feel really convenient – until you have to restore a lot of data from them, or migrate that data to a new Mac. The fastest, most cost-effective, robust and feature-packed backup is the one that you make to a USB or Thunderbolt hard drive. When you make a backup to a local disk, your backup can take advantage of features unique to APFS, like support for cloned files, sparse files, and filesystem snapshots. That local backup will use storage space more efficiently, is compatible with Apple's Migration Assistant, and offers a rich backup history that gives you access to older versions of your files.

If you don't already have a backup on a directly-attached USB or Thunderbolt device, we offer some hardware recommendations here, and you can learn how to set up this backup in the Establishing an initial backup Kbase article.

Automate your backup

We see too many cases where folks don't have their backups configured to run on a regular basis. A lot of people will say "Any backup is better than no backup." To an extent, sure, but people are usually pretty disappointed if they need to restore from a backup and find out that it hasn't been updated for six months. Even if you have multiple backup solutions in your backup strategy, you should configure all of your backups to be automated. Click on CCC's Automation selector box to find an automation option that works best for you. CCC offers many scheduling options and limits so you can make backups that work with your schedule.

Hourly Automation


Inconvenient to have the backup disk attached all the time?

We recommend updating your backup... Read More

Mike's picture by Mike | January 18, 2023

We field a lot of support requests, and similar to a doctor's office, we see some extreme cases. One of those interesting extreme cases are folders with high file counts. Any time a folder has more than a few thousand items in it, the filesystem is going to be a lot slower when working with that folder. Adding a new file, for example, requires that the filesystem compare the new item name to the name of every other file in the folder to check for conflicts, so trivial tasks like that will take progressively longer as the file count increases. Gathering the enormous file list will also take progressively longer as the list gets larger. The performance hit is even more noticeable on rotational disks and network volumes, so we often see these sticking out in backup tasks.

Sometimes high folder counts can bring a backup task to a halt

Task encountering a folder with a high file count

Last week, one of our users found the task as shown above. Upon closer analysis, we determined that the "media" folder had 181,274 files in it. In other words, more than 10% of the files on the whole startup disk were in that "media" folder. In extreme cases like this, the delay to retrieve a file list can be so long (i.e. longer than 10 minutes) that the task aborts with an error, e.g.:

The task was aborted because a subtask did not complete in a reasonable amount of time. Or,

The task was aborted because the destination filesystem is not responding.

These are typically pretty wild cases that benefit from some human intervention. For example, I recall seeing an AddressBook application support folder that had more than 2.5 million image thumbnails in it. Nobody has that many contacts! That wasn't an isolated incident, either, we've seen that same AddressBook folder implicated at least a half dozen times. Cases like that usually point out a software failure in the application that is creating the files – a failure to sanity-check its data store, or to put a sane limit on how many log files it creates. Sometimes, like in the Telegram example above, it's just short-sighted design.

For a contrasting example, consider how Mail organizes a potentially astronomic list of files. If you navigate to the hidden Library folder in your home folder, then to Mail > V10 > {any UUID} > {any mailbox} > {another UUID} > Data, you'll see folders named by number, four layers deep, until you finally get to a Messages folder with actual files in it. While this nested hierarchy makes it annoying for a human to find a specific email file, that organization limits any individual folder's file count and optimizes Mail's ability to quickly collect those resources from the filesystem.

Some data stores with potentially-high file counts

Here's a list of some common culprits we'... Read More


Mike's picture by Mike | October 18, 2022
CCC is ready for macOS Ventura

It's Fall here on the top of the globe, which means that temps are getting cooler, pumpkin seems to be in everything, and apples are in season. And of course, Apple is about to drop another new upgrade to macOS: Ventura. We've been testing the new OS over the summer, and I'm pleased to report that CCC is ready to protect your data before and after you apply this upgrade – we added official Ventura support to CCC 6.1.3, which we posted back in September.

Every year we make a handful of changes to CCC to support changes that Apple makes in the new OS. We have a mixed bag this year, and I wanted to point out just a couple things that work a little differently. Overall, the changes are pretty bland, which means this article will not be very exciting. So to spice things up, I added a recipe for Pumpkin Spice Muffins at the bottom.

System Preferences → System Settings

The name change seems innocuous, but the changes that Apple made to this application are really significant. Initially I was really flustered with the new layout. I finally gave up and accepted that I'll just have to use the search bar to find things. Apple was always meddling with the order of items in System Preferences, though, and I recall feeling disoriented every year in this application. Now that I've accepted using the Search feature, I think I'm actually a bit faster at using it.

Privacy Settings

Apple introduced new privacy settings in macOS Mojave, and they've been tweaking them in every OS release. These settings have been pretty annoying for developers and users alike. Apple doesn't offer a programmatic interface for the "Full Disk Access" controls, so the best we can do is coach users through the procedure. Normally that works fine, but it was still multiple steps, and users could take a wrong turn at any of those steps.

I'm delighted to report that Apple made a modicum of improvement to this process in Ventura. They finally dropped the padlock paradigm, so pre-authentication is no longer required to unlock the settings in the Privacy panel. As a result, the procedure for granting Full Disk access to CCC and its helper tool on Ventura is now one step! When you start dragging CCC's "privacy fish", CCC will open the System Settings application and reveal the Full Disk Access controls, ready for the drop. At that point you're prompted to authenticate, and then you're done. Progress!

Login Items

Yeah, "login items" – you can imagine how exciting my summer was 😉. In Ventura, Apple deprecated an older mechanism for adding login items, and replaced it with a new mechanism. Normally I don't immediately adopt brand-new features like this (because it makes it more complicated to support multiple OSes with one... Read More


Mike's picture by Mike | May 19, 2021

We've had so many new features in the oven for a while, and now we're finally ready to share it with the world! CCC 6 offers unprecedented accountability for your backups and insight into what's changing on your Mac, plus a brand new file copier that's faster, smarter, and designed to adapt to Apple's fast pace of OS and filesystem innovation.

Take a look at what's new in CCC 6:

The core CCC backup features you know and love are now better than ever!

Faster backups with our next-generation file copier

We've completely rebuilt our file copier to take advantage of the performance characteristics of modern storage. Built on a multi-threaded design, our new file copier provides a foundation for many of the new features noted below, and paves the way for many new features in the future.

Quick Update: Update your backups up to 20X faster

CCC can now tap into the macOS FSEvents service for a list of folders modified on the source since the last backup rather than scanning every folder for changes. Especially for tasks involving a destination network volume, the performance benefit of this feature cannot be overstated!

Redesigned Interface with Dark Mode

It’s been a while since we’ve given CCC’s interface an update and think you’ll enjoy its sleek new look. CCC’s main window is reorganized to make it smaller while making many of the controls and font sizes larger. We completely redesigned every element in CCC to offer a high quality Dark Mode experience. CCC now offers more detailed progress indication while a task is running, including a time remaining estimate. File processing and transfer rates are now... Read More


Mike's picture by Mike | May 19, 2021

CCC 5.1.27 and CCC 6 can make bootable copies of the system on Intel and Apple Silicon Macs (11.3+) right now, and we'll continue to support that functionality as long as macOS supports it.

But as Apple's platform continues to evolve, we have to design our recovery strategies around the current hardware capabilities. A bootable external device may not be a part of that strategy. CCC can do so much more than just make copies of the system, and now is the right time to revisit your backup strategy and make it even better with some of the new features in CCC 6.

For decades, Mac users have taken for granted the Mac's "External Boot" feature. Prior to Mac OS X, people could simply drag and drop the System folder from one volume to another; presto, external boot volume. When Apple made it more complicated with Mac OS X, we pioneered the "bootable backup" solution (nearly 20 years ago!), and this has been a feature we've reliably supported on every new Mac and every new OS since then.

But Apple has never been afraid of shaking things up to blaze new trails. Big Sur and the new Apple Silicon Macs have shaken up the way Mac users will recover from hardware failure.

Big Sur's Big Change

All on its own, Big Sur introduced a significant new change to the creation of an external boot device. The operating system now resides on a cryptographically sealed "Signed System Volume" that can only be copied by an Apple-proprietary utility, "Apple Software Restore" (ASR). We were already familiar with ASR, so fairly quickly we were making bootable copies of Big Sur back in November. It hasn't been perfect though. We've performed tens of thousands of ASR clones at this point, and we've discovered that ASR is just not as robust as our own file copier. There are many scenarios where ASR simply fails with no explanation. ASR is also very one-dimensional; choosing to copy the system requires that we sacrifice other backup features, e.g. we cannot copy the system and retain versioned backups of your data, we can't evaluate what was copied, we can't exclude items from the initial backup, we can't save checksum data for later verification. So, while we're certainly able to make a bootable copy of the system with ASR, it starts to feel like using it causes us to lose sight of what's actually important to back up – your irreplaceable data.

Apple Software Restore isn't quite ready for the new Apple Silicon Mac storage

When Apple introduced Apple Silicon Macs, we discovered another snag. The "Apple Fabric" storage in these Macs offers per-file encryption keys (like the storage in iOS devices), and for months, ASR didn't work with it. Apple partially resolved that in macOS 11.3, but even now using ASR to clone the system back to the internal storage of... Read More