Time Machine on a notebook

[xli_ne]

How does Time Machine work with a notebook that isn't plugged into a external HDD all the time?

Does it backup any changes when you plug it in at night? or how does it all work?

 

[cmaier]

How does Time Machine work with a notebook that isn't plugged into a external HDD all the time?

Does it backup any changes when you plug it in at night? or how does it all work?

It keeps track of what files are changed, then backs them up when next you are connected.

 

[pna]

It keeps track of what files are changed, then backs them up when next you are connected.

Just to build on this, from how I understand TM to work in this scenario, it doesn't keep track of enough information to, say, still back up all of the hourly updates it normally would have backed up if it had been plugged in to your external HD. When you plug it back in to the external, it will just start backing up everything since the last time it ran as one big update.

In other words, if you had your notebook plugged in to the external HD from noon until 11 pm, TM would make a series of 11 hourly backups for you to recover back to. If you had your notebook unplugged from the HD from, say, 2-5 pm, when you plugged it back in at 5 pm, it would just make a single backup that would document what had changed between 2 and 5 pm rather than filling in the three hourly backups that you had missed.

In practice, this would rarely matter, given that the hourly backups are only kept around for a day, but you get the idea.

 

[cmaier]

Just to build on this, from how I understand TM to work in this scenario, it doesn't keep track of enough information to, say, still back up all of the hourly updates it normally would have backed up if it had been plugged in to your external HD. When you plug it back in to the external, it will just start backing up everything since the last time it ran as one big update.

In other words, if you had your notebook plugged in to the external HD from noon until 11 pm, TM would make a series of 11 hourly backups for you to recover back to. If you had your notebook unplugged from the HD from, say, 2-5 pm, when you plugged it back in at 5 pm, it would just make a single backup that would document what had changed between 2 and 5 pm rather than filling in the three hourly backups that you had missed.

In practice, this would rarely matter, given that the hourly backups are only kept around for a day, but you get the idea.

Correct. It just will back up one version of each modified file; it won't keep track of intermediate changes. It's not intended to be a version control system, otherwise instead of once per hour it would back up every modification. Thats what CVS is for