Archive for July, 2010

How to back up your Mac using Arq


July 21st, 2010

When I started developing Arq it was partly because I couldn’t find an existing online backup offering that gave me enough control. I wanted to control exactly which files would be backed up, and I didn’t want to be constrained by rules that many of the “unlimited backup” offerings had like excluding network drives, excluding applications, etc.

So Arq lets you back up anything you want. But then the question is, what should you back up? The following is my suggestion for a basic backup of your files on your Mac.

Basic Backup Using Arq

When you first install and launch Arq, it asks your for your Amazon S3 “keys” and a few other things. Then it asks if you’d like to choose your own files for backup, or back up your home folder minus a few unnecessary items:

Screen shot 2010-07-21 at 8.02.18 AM.png

If you picked “I’ll manually add folders to back up” and you’ve changed your mind, here’s how to set up Arq to back up your home folder minus the unnecessary items:

1. Add your home folder

Click the + button at the bottom left of the Arq main window.

Screen shot 2010-07-21 at 8.10.25 AM.png

Pick your home folder (/Users/<yourname>) and click OK.

Screen shot 2010-07-21 at 9.27.33 AM.png

2. Add some excludes

Click the “Edit Excludes…” button.

Screen shot 2010-07-21 at 8.08.05 AM.png

Add 3 excludes.

Screen shot 2010-07-21 at 8.15.33 AM.png

Make sure the first 2 are set to “relative path” instead of “name”.

Click OK.

Backing Up Applications Using Arq

If you want to back up your applications, add the Applications folder.

Screen shot 2010-07-21 at 8.28.12 AM.png

Many applications put some of their support files in /Library/Application Support, so add that too.

Screen shot 2010-07-21 at 8.29.02 AM.png

Advanced Backup Using Arq

If you prefer, you pick and choose specific folders to back up instead of backing up your entire home directory.

WARNING: If you choose to do this and you later create a new folder in your home directory and start putting important files in there, you’ll have to remember to add this new folder to Arq or else it won’t be backed up!

I back up the following folders as separate items in Arq:

  • Application Support (/Library/Application Support)
  • Applications (/Applications)
  • Documents
  • Library, excluding files/folders named ‘Caches’ and ‘Logs’
  • Music
  • osaka iPhoto Library (my big iPhoto Library, named after my computer), excluding files/folders named ‘iPod Photo Cache’
  • src (my work files), excluding files/folders named ‘build’ and ‘bin’

Time Machine and Arq

Time Machine and Arq are complementary. Backing up using Time Machine to another disk is cheap and fast. If you’re backing up to a Time Capsule via Wifi it’s very convenient because it just happens; there’s nothing to plug in. If you’re backing up to a USB drive, you’ll have to remember to plug in the USB drive periodically. Restoring is fast because you’re reading from a USB disk physically connected to your Mac, or from a Time Capsule over Wifi.

But Time Machine doesn’t cover all cases. If someone breaks in and steals your computer, they may steal your Time Capsule or USB drive as well, and then your files are gone forever. If fire, flood, or lightning strikes, you may lose both your computer and your backups; files gone forever. And if you travel often, you’ll have to bring along your USB drive or Time Capsule, or backups won’t happen until you get home and stay home long enough for a backup to complete.

Arq covers those cases that Time Machine doesn’t. The backups are off site at Amazon’s servers, safe from your theif and your natural disasters. They’re even safe from disaster at an Amazon site because Amazon replicates your data at several sites. And Arq works whenever there’s an Internet connection, so backups still happen when you’re on the road.

Arq 1.5 is out!


July 16th, 2010

I’m really excited to ship Arq 1.5!

It includes scheduling options like once-per-day backups and manual-only (one of the most requested features) as well as Pause/Resume and Back Up Now functions. It also includes a whole bunch of refinements and bug fixes.

To get it, pick “Check for Updates” from the menu in Arq, or download it from the product page.

Here are the details:

Feature Additions

  • Configurable backup schedule: hourly, once/day at a certain time of day, or manually.
  • Back Up Now feature.
  • Pause backups for an amount of time you choose. Resume early if you wish. (‘Pause’ is better than ‘stop’ because you won’t have to remember to start it again).
  • Progress indicator next to the “Other Computers” heading in the source list (on the left side of the window) so you can tell when Arq is still scanning for other computers’ backups in the S3 data.
  • More informative status messages such as “Calculating upload size” and “Finishing backup” instead of just “Backing up …”
  • Better communication of error and warning conditions.
  • Estimated backup time is now calculated based on start of backup, not start of calculating upload size.
  • More accurate progress bar in 2 scenarios — when saving the “packs” of small files, and when re-doing an initial backup that was aborted.
  • More useful logging output when log level is set to Info.
  • Much faster loading when browsing backups.

Bug Fixes

  • More efficient caching of the set of objects in S3.
  • Fixed an issue where calculating the upload size for a backup was incomplete when a permission error was encountered.
  • Fixed issues with high memory usage in both Arq and Arq Agent.
  • Fixed an issue that was preventing the “Start at Login” preference from persisting.
  • Fixed 2 issues where packs weren’t being read correctly, leading to “object not found” errors.
  • Fixed regression bug in restoring file permissions correctly for root-owned files.
  • Fixed an issue where the folder’s progress bar was occasionally disappearing.
  • Fixed an issue with trying to read extended attributes on files that don’t support extended attributes.

Enjoy! If you have any feedback or questions I’d love to hear from you! Just email Thanks!

- Stefan