MAC devices form a significant percentage of home and business use devices and it follows that a large amount of data being created today originates from such devices. The rising volume of data brings into focus the MAC OS backup and recovery options available. In the next couple of posts we will touch upon Time Machine and Time Capsule the inbuilt Back-up options available with Mac and then at some options available out there to be used in combination with Time Machine and our own wish list of what a great new Mac OS backup solution.
Time Machine – Time Capsule
The MAC OS is a modified BSD Unix. Disaster Recovery and Back-up strategy therefore follows what works for MAC supported File systems. The inbuilt backup mechanism is the Time machine – Time capsule. The Time machine is a backup software that backs up the data to any external drive and the Time Capsule a proprietary hardware that supports such backups for multiple MAC clients. The supported file systems include HFS+.
Some of the advantages of this mechanism are
- Allows backup of changed files every hour
- Allows automatic selection of the most recent backups each night and discarding the rest
- Allows the recovery of previous and deleted versions of files almost immediately
Let us focus on some of the challenges encountered with Mac OS Backups
- Local disk backups are not supported
- Incremental backups mean that whole files are backed up again even if the changes are trivial – this is an obvious problem for large files for file level backups
- Backups are not themselves bootable – this makes the DR procedure time consuming and complicated for the lay user
- Backup destinations have to be HFS+ partitions – Time Machine cannot backup to non-HFS external drives. Since HFS+ is not readily readable by other OS this effectively renders the drive a single purpose storage.
- There can be only one destination at a time, changing the destination on the fly, requires deeper knowledge of configurations and hence is not simple.
- Backup schedules are inflexible and can only be changed using third party utilities. This may introduce incompatibility and may become difficult to maintain across upgrades.
- Time Machine backups cannot be moved to different disks easily, upgrading or exchanging external disks with existing is tricky
- De-duplication is not offered.
- Performance slows while the backup is running. Overall system performance degrades if Time Machine drive is mounted all the time.
- “Include-exclude” for files is not flexible.
- File compression is not used on destinations
- The external backup disk is required to be of a much higher capacity for meaningful protection or the Time Machine storage management prioritizes the most recent backups and deletes older backups automatically. It is this not under the control of the user which backups to keep.
- Add-on downloadable utilities need to be used to adjust Time Machine configurations to suit user’s needs (manual backups, backups to non-Time Capsule network shares, change to Time Machine scheduler
In the next post we will touch upon the various options available for use with Time Machine. In the meantime – what do you think of Time Machine and Time Capsule ? Do you see any other significant advantages or challenges with these solutions ?
About the Author: Mandar Shukla is an avid tech enthusiast, working across multiple domains of Backup, Archiving & Storage, Enterprise software performance, Visual computing, Cloud Lifecycle Management. He is a QA professional since 2006 and follows emerging trends in technology to derive inspiration and imagination required for his QA activities.