time machine

Hi:
I have never used "time machine." I assume that it is necessary, if you want to back up to an external hard drive, that it be connected to the computer at all times.

I assume that it is necessary, if you want to back up to an external hard drive, that it be connected to the computer at all times.

Click to expand...

Yup, well at least it needs to be connected for Time Machine to do its thing.

For more info, open Time Machine and click the "?" for some, or do a web search on your question(s).




- Patrick
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pm-r said:

Yup, well at least it needs to be connected for Time Machine to do its thing.

For more info, open Time Machine and click the "?" for some, or do a web search on your question(s).




- Patrick
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Click to expand...

Thank you

Just one small point for clarification, I hope.

If you own a Desktop Mac (iMac), then the External Hard Drive (EHD) should remain mounted and Time Machine will do its duty, hourly. The first Backup (BU) will take a while, but subsequent BUs are incremental and will be much shorter. It does all this in the background.

But if you own a Notebook, then the situation is different. Sure, you mount the EHD and carry out your initial TM BU; and you can keep the EHD mounted until it's time to take the Notebook with you. Then you must unmount the EHD.

During the time the Notebook is on its travels with you, TM creates snapshots of the incremental BUs and store them temporarily on the Mac's HD. Then, when you get home, remount the EHD and the snapshots will automatically to transferred to the EHD; thus clearing the storage space on the Mac's HD.

Hope that makes some sense.

Ian

Then, when you get home, remount the EHD and the snapshots will automatically to transferred to the EHD; thus clearing the storage space on the Mac's HD.

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Good valid and useful point Ian.

And I didn't notice any of the other usual Mac backup/cloning apps being mentioned in case the OP was interested.

CCC for example has an option to do its thing when the "backup" drive is re-connected.




- Patrick
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The external TM drive doesn't have to be connected at all times, but you loose the functionality of having an up to date backup if it isn't. I have one external drive mounted at all times and a second one that I connect once a week (or 2 if I'm lazy) which then lives in a fireproof safe. TM is set to alternate between the drives but doesn't get upset if one is missing. It just backs up to the one connected drive until the other is connected.