File Systems Flashcards
How are disks, partitions, and volumes different from one another?
Disks are the storage hardware
Partitions are logical divisions of a disk used to define storage space.
Volumes are contained inside partitions and are used to define how individual files and folders are saved to the storage.
What are the 2 primary partition schemes for Mac-formatted disks? What are their differences?
GUID Partition Table (default on Intel Macs)
Apple Partition Map (default on PowerPC Macs)
What 2 volume formats are supported for an OS X system volume?
Mac OS Extended (Journaled)
Mac OS Extended (Journaled, Encrypted)
How does file system journaling work?
It records what file operations are in progress at any given moment.
What are the 4 erase options available in Disk Utility? How are they all different?
Fastest - replaces volume’s directory structure
Good Security - writes zeros on top of all previous disk data
Better Security - writes 3 separate passes of information on top of previous disk data
Most Secure - writes 7 separate passes of information on top of previous disk data
How does the Secure Empty Trash feature in Finder work?
It preforms a 7 pass erase on the contents of the trash folder
How can you ensure that previously deleted items are securely erased?
From the Erase tab in Disk Utility, you can choose to securely erase the free space of a disk or volume.
How can you encrypt a disk without losing its contents?
Secondary (or Control) clicking the disk and then choose Encrypt
What 4 methods can be used to eject a volume or disk in the finder?
Drag the disk icon to the trash
Press and hold the eject key for a few moments to unmount and eject optical media
Select the item and choose Eject from the file menu
In Finder, click the small eject button next to the volume
What’s the potential side effect of improperly unmounting or ejecting a disk or volume?
Data corruption (The system will automatically verify and repair the disk the next time it is available)
How does FileVault 2 protect a user’s data?
By using strong XTS-AES 128 encryption
What are the system requirements for using FileVault 2 (2 things)
Must have hidden OS X Recovery HD on the startup disk
Any Legacy FileVault accounts must be decrypted and returned to normal accounts before enabling FileVault 2
Which users are allowed to unlock a FileVault 2 protected system?
Any user that’s FileVault enabled
How can you unlock a FileVault 2 protected system when all user accounts have lost their passwords?
Use the recovery key that was generated during the FileVault 2 setup
How do you identify the ownership and permissions of a file or folder in the finder?
By using the info or Inspector windows of the Finder
How do ACLs differ from standard UNIX file system permissions?
Standard UNIX file system permissions allow only for permissions to be set for one owner, one group, and all others.
ACLs on the other hand, allow for an essentially unlimited list of permissions entries.
What’s the locked file flag?
It prevents anyone, including the item’s owner, from editing an item. Only the item’s owner can unlock the item to modify it.
Why is the root, or beginning, level of a user’s home folder visible to other users?
So they can navigate to the Public shared folder
How does the default organization of the file system allow users to safely share local files and folders?
Every home folder contains a Public folder that other users can read and a Drop Box folder that other users can write to.
What’s unique about the permissions of the /Users/Shared folder?
The Shared folder is set up to allow all users to read and write files, but only the user who owns an item can delete it from the Shared folder. This is accomplished by using the sticky bit permissions setting.
What does it mean when you choose the option to “ignore volume ownership” in the Finder? What are the security ramifications of ignoring volume ownership?
You can choose to ignore ownership on any non system volume. This will ignore any ownership rules and grant any logged-on user unlimited access to the contents of the volume. It’s a potential security risk.
Which 2 built-in OS X applications can be used to gather information about storage devices?
Disk Utility
System Information
What does the Disk Utility Verify and Repair feature do?
It is used to verify or repair the partition scheme and directory structure of a volume.
What’s target disk mode and how is it engaged?
It shares the Mac computer’s internal disks through FireWire or Thunderbolt ports. It can be engaged from Startup Disk preferences or by holding down the T key as you start the Mac
What permissions are modified by the Disk Utility Repair Permissions feature
It repairs only the ownership and permissions for items installed by Apple. However, this may resolve issues with third-party products.
How can you reset a user’s home folder permissions?
Reset Password application on OS X Recovery
