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how to track your clones


Last week I was asked whether I could produce a script that would keep track of Carbon Copy Cloner backup tasks so that a user could tell which of many, multiple backups of the same source disks were the most recent.

Of course, CCC has its own Task History and Disk Center functions to provide information, but these turn out to be insufficient in common scenarios. To see why, let’s consider a hypothetical task set-up and recovery situation.

In this situation, let’s suppose I’m keeping 2-hourly, daily and weekly clones of my mac’s internal disk. While I’m logged in to my mac, I can of course check CCC’s Task History to see when the last back up was, the destination, and whether it was successful or not.


However, suppose the internal disk fails – just the situation for which I keep my CCC backups on a regular schedule. Which disk contains my latest backup? The information from CCC’s history task is on the failed internal disk, so it is not now available to me. Of course, each backup contains CCC’s earlier History too, but there’s several problems here. First, these cloned task histories do not contain the history from the *last* task (that’s only written to the source disk after the last backup completes). Second, to compare them, I’d have to boot each clone individually – a time-consuming and not terribly convenient process. Third, CCC’s ‘Disk Center’ only provides backup information about connected disks if the current startup disk was used to run the backup task. Thus, if I backup Disk B from Disk C, that information won’t be available to me when I startup my mac with Disk A.

Before I discuss the solution to this, let me just complicate the scenario further. I have two other macs – two 13″ MacBook Pros that have been going strong since 2009 – each of which I backup to individual clones. There’s no way for me to see all the backup dates from all my macs with CCC. Further, we don’t need to consider only disk failure as a reason to need comparative backup history. Since some files are shared or swapped across my three macs, there’s no way to find out from CCC’s Task History or Disk Center when the latest backup of any particular one of those files was made, or on which backup disk I can find it. For example, the connected disk ‘MBP Z Clone’ is a scheduled task on my MBP, but looking at this disk when connected to my iMac gives me no information about its backup history:


Fortunately, CCC has two features which make our problems solvable. First, each source disk keeps detailed logs of the backups it has run (from which the Task History and Disk Center info is constructed); secondly, CCC allows us to run a shell script after each task has completed.

These two little features are going to allow us to build a shell script that will write a special log file to the destination after each task completes, and then retrieve it and compare it against both the current source and other disks. That means we’ll be able to get CCC backup data from any disk we connect to any mac, since the data will be stored on the destination disk itself thanks to our shell script (for the technically minded: to avoid permissions problems, the script writes to /Users/Shared/ if it’s a bootable clone, or to the root of a disk that isn’t).


That’s the outline of the problem and the solution. What started out as a simple AppleScripting task soon blossomed into a full-blown app. Although much of the background work I’ve outlined above is achievable via AppleScript, displaying the data effectively is rather cludgy, even if one uses some of the excellent scripting libraries like Shane Stanley’s ‘Myriad Tables’ to improve on the stock AppleScript offerings.

Accordingly, after about a week or so of wrestling with an acceptable solution, I finally came up with the Disk to solve all these problems in one go and add a few niceties on top. 😉

Whatismore, since it’s Christmas :D, I’m publishing this as a free utility on my software site, Check out Disk Inspector’s support and download page here:

Here’s a quick overview of the main features:

1. See dates of all connected disks that have been backed up via CCC*
2. See the latest backup and (if available) Time Machine backup for the current source disk
3. See the OS Version and Build Number on connected, bootable drives
4. Open any disk’s root folder in the Finder by double-clicking its name in DI’s main view
5. See an estimate of the total and available space on each disk (rounded to the nearest GB)
6. Save all the data to a log file for easy record keeping of your backups

* after completing Disk Inspector’s set up procedure


For full instructions refer to the Support page, but the basic idea is that on first launch, you run the ‘Set Up’ wizard to configure your tasks in Carbon Copy Cloner. Disk Inspector’s ‘Set Up’ wizard walks you through 5 simple steps to accomplish all this.


Once you’ve completed the set up procedure and each of your scheduled CCC tasks has run, you’ll start to see information for each backup disk in Disk Inspector’s main view on any mac (or on the same mac booted from a different drive) that you subsequently connect those disks to.

Disk Inspector runs on 10.10 and higher.

Enjoy, and Happy holidays to all! 😀

how to see what Time Machine has and will backup

Screen Shot 2016-05-13 at 21.57.25
If you find Time Machine’s taciturn silence on what it has and will do a bit frustrating at times, the command line utility tmutil can offer you a bit more insight.

In particular, if you’d like to see what Time Machine is going to back up just before it’s about to run, execute the following command in the Terminal:

tmutil compare

That will compare the machine as it is now against the last backup (See the man page for more options on the output). It took about 5 minutes on my mac, but I have a small hard drive. It could take somewhat longer depending on how much data you’ve got to trawl through. Remember that you’re doing a diff on a moving target, so the less you can use the machine for other tasks while this command is running the faster it’ll complete.

On the other hand, you might want to know more about what Time Machine has just done after a backup. Which files did, or did not, get changed, added or removed?

You can find out what got backed up after the task finishes by comparing the most recent snapshot (the one that’s just completed), with the previous one (this is much faster, took about 35 seconds here). You can do that in Terminal, too, but the syntax can be a bit tricky. To make it easier, here’s a handy AppleScript that will do it for you. Just pop it into the (Apple)Script and hit the ‘Run’ ▶︎ button.

# This script compares the most recent backup to the previous one
# indicating what was changed, added or removed

set backupList to paragraphs of (do shell script "tmutil listbackups")
if (count of backupList) < 2 then
display dialog "Sorry, couldn't find anything to compare. Try again after the next backup"
set path1 to quoted form of item -2 of backupList
set path2 to quoted form of item -1 of backupList
do shell script "tmutil compare " & path1 & " " & path2 & " | open -f"
end if

sync notes between mac and android

Having an Android phone and Mac computer…not what  intended…and syncing between them can be awkward. I use Dropbox on both and avoid iCloud for various reasons (some related to security), but I’ve always found syncing notes a problem.

My Android phone has a couple of notes apps , and my mac has, of course, the horribly-lemon yellow, Stickies, and even Reminders can be used , not to mention TextEdit. The result was that I found I was keeping notes in several different places and then not knowing where to look for something, hunting around trying to remember which application I’d left some obscure, half-remembered note to myself in.

Then I discovered Notational Velocity. This is a great, free, open-source app built for OS X and it’s got all the simplicity I need. It has a combined search and enter field reminiscent of Spotlight, and the interface is clean, fast and efficient, requiring minimal keystrokes or trackpad movements.

On top of that, it can link to a web-based notes app called (also a free service). Notational Velocity and will sync to NV’s sister-app, Notational Acceleration, which is basically NV for the Android platform (and if you have an iOS device, there’s a Simplenote app for that too). Once you’ve got all of these set up, you have a notes app that you can use on your android phone, you mac, or log into from someone else’s computer, and the whole lot will keep in sync automatically!

Total cost: zero! 🙂

how to back up your Mac – the best way!

iCloud? Time Machine? Noooo……! We’re talking about the best way to backup your precious data, not the most convenient way…

What’s wrong with using the cloud? The fact that you need an internet connection, a password to be accepted, to act in accordance with the T&C of your cloud provider, the fact that someone – government, corporation, hacker – could interfere with your data, lose it or just add unwanted stuff to it. Also, if you want to backup your whole system then the various free storage offers are not going to be big enough to do the job, and you’re going to end up paying a lot more than if you backup your system properly.

How about Time Machine? Yes, it’s simple and convenient and pretty much automatic, but its not secure. TM has three major problems. First, it doesn’t allow proper archiving so anything you delete from your HDD will eventually get deleted from TM. Second, it doesn’t tell you what it’s doing before it does it, meaning you are at the mercy of its automated decisions. Third, it’s not bootable. If your whole system crashes or your HDD just fails, Time Machine won’t help you. You’ll have to restore the system or replace the HDD before you can use your machine again.

But there is a much better way, and aside from you providing the hardware (a couple of external hard disks), one that’s also free. The most secure system is to run an hourly or daily scheduled cloner on one disk, and a weekly cloner on the other. You can use SuperDuper or, my own favourite, Carbon Copy Cloner.

If you want to read up on and understand the various backup options and what they entail, you can’t do better than to read this superb post by Apple Discussions member ds store.

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