When troubleshooting OS X it helps to be prepared with an arsenal of tools that can help narrow down what exactly is contributing to the problems at hand. Having tools that help you investigate files, monitor system events and input or output, and control aspects of the hardware is very useful to have when trying to perform troubleshooting tasks.
If you want--or need--to troubleshoot a problem with your Mac, here are some recommended tools. You don't need to keep these on your system at all times, but knowing they're available makes them easy to access in the event a problem arises.
This tool is a great option for accessing the contents of OS X installation packages. Though it can be used as a replacement for Apple's Installer program, its main benefit is the ability to extract individual files and folders from packages, thereby allowing you to replace missing programs and system files without needing to reinstall OS X. While Time Machine and other full-system backups help prevent the need to do this, there are still times when this is useful to have. In addition to managing OS X installations, Pacifist can help you identify the exact contents of third-party installation packages, which may help you determine what exactly is being installed on your system and where.
The OS X fsevents feature is a convenient option to have, since it tracks what changes are made to the file system in real-time. The tool called fseventer allows you to monitor the updates, and either lists or graphs them in a dynamic folder hierarchy view. This makes it quite convenient to isolate which files are being edited by applications and system processes when the programs are run or when settings are changed.
Apple's TextEdit program is a good basic text editor, but if you manage formatted text such as that in configuration files (namely plist files in OS X) on the system, then you may need a more robust option. TextWrangler is a free tool that offers a few convenient options for managing text files, with one of the more beneficial options being its ability to browse through hidden files and folders on the file system.
- Little Snitch
If you are at all interested in figuring out which applications call out to remote servers and wish to have a bit of control over these actions, then having a reverse firewall like Little Snitch installed is a must. In addition to monitoring system features and third-party programs, reverse firewalls can also thwart malware attempts that try to phone home and steal your personal information, provided you are diligent and proficient at monitoring the system's network activity (a learned but doable process).
Many Mac systems come with dual graphics cards, allowing for low-power modes and dynamic switching when graphics demand is high. Sometimes having a little more control over the dynamic switching routines and being able to stop them can help address graphics problems that can arise, such as the black-screen bug that affected mid-2010 model MacBook Pro systems when OS X Lion was released.
In addition to the graphics processors, another dynamically adjustable hardware component is the system fans, which are usually kept at low speeds but should increase in power as the system heats up. While it is best to allow the system to manage the fan speed on its own, there are times when you might wish to force the system to increase the fan output to keep the system cooler, in which case smcFanControl is a convenient utility. Such adjustments also can be used to determine if the system's system management controller (SMC) is responding properly to settings changes, which may indicate whether an SMC reset is needed.
- Grand Perspective
If your hard drive is filling up, you may not be able to easily identify why this is the case or see what files are responsible for it. Having a tool like GrandPerspective (another similar tool is Daisy Disk) that will show you the relative size of the files on your disk is a great option to have, and can greatly help you pinpoint whether disk usage is from a problematic log file, duplicate files, or simply having too many files on your disk.
Beyond the tools mentioned above, there are some additional tools and programs that you might benefit from installing on your system. Even if they are not directly related to troubleshooting a specific aspect of the Mac OS or Mac hardware, they can nevertheless be used to help address problems.
- Malware scanner
While malware on OS X is still quite rare and relatively insignificant, its prevalence is rising, with 2011 showing the most malware on the Mac than the platform has seen since the release of OS X. As a result, having a malware scanner is not necessarily a bad idea, and can also help by detecting malware designed for other platforms, which can better protect everyone. There are many antivirus utilities available for OS X, a few of which I outlined in my antivirus recommendations for OS X.
- Cleaning tools
One of the common routines for clearing odd slowdowns and other undesired behavior in OS X is to perform a general maintenance routine. To do this, you might benefit from having a maintenance tool on your system, such as Onyx, MacCleanse, and Lion Cache Cleaner. I have mentioned these and others in my guide to performing a general maintenance routine, which in many instances is a good starting point for tackling odd Mac problems, particularly those that deal with performance.
- Optional third-party programs
While OS X contains a few tools such as Disk Utility that can be used for addressing problems, many times these options are inadequate for addressing or diagnosing problems either with the hardware, file-system configurations, or data integrity. To tackle these, there are some third-party tools that are specifically designed to manage file and file-system errors and other hardware problems. DiskWarrior has a reputation for being a very robust file-system checker, and in many instances will fix problems with the OS X file-system format that Disk Utility claims cannot be fixed. In addition, there are tools like Drive Genius and Tech Tool Pro that also are great options to have.
Do keep in mind that even though many maintenance and cleaning tools such as OnyX contain disk- and preference-checking options, these usually just interface with Apple's built-in routines instead of providing their own uniquely engineered approaches. As a result, these tools will usually show the same results as Apple's Disk Utility when run.
Troubleshooting aspects of OS X stem beyond file-system and OS features, so in addition to using system tools it may help to double-up on programs that you might use for day-to-day productivity. For instance, while Apple ships Safari with OS X, it is highly recommended to install least one more browser such as Firefox, Chrome, or Opera. If for some reason an error prevents Safari from launching or the program will not work on some Web content, then you can likely get by with these alternative options. The same idea goes for media players (VLC and MPlayer OS X Extended are good alternatives to Apple's QuickTime Player), and even Office tools, where programs like Apple's iWork suite can in many instances work as well as if not better than Microsoft Office for office work.
Do you have any recommendations for troubleshooting tools that could be added to this kit? If so then let us know below in the comments.