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CC88

macrumors 6502
Original poster
Sep 29, 2010
488
117
Dear all

I would like to 'freeze' a time machine backup. I want that this backup will never be overwritten or deleted.

Is there a way to do it? I want to mantain the current state of the system to use it in the future and also use this space on the time machine disk that's a 16tb one.

Is is possibile to tell Time Machine to lock a backup and not delete it in any way?

Thanks a lot.
 

HobeSoundDarryl

macrumors G5
Several simple options:

Eject the drive. If there's nothing to overwrite, the last Time Machine backup will persist there for years.

Copy the entire backup to a different drive that you can put away. You might even be able to burn it to a disc (truly Read Only) or copy to a USB stick. Then, when you want to revive it sometime, copy it back from that source. This option would let you "have your cake and eat it too" in that you would basically keep a copy of this backup as is AND be able to continue making new Time Machine backups going forward.

Turn off Time Machine. If you ask it to no longer do its thing, the last backup persists until you turn Time Machine on again. Of course, this means that anything you create or add to your system won't be backed up at all, so choose wisely here.

Lastly, go buy a smaller drive and then immediately TM backup your Mac. When it is done, eject it and it will be your current copy that will persist for upwards of years on an unplugged drive. This is basically the same as the first suggestion except that you are making a fresh backup to the new drive instead of copying the existing backup to another drive.

If this is about creating a way back ahead of potentially upgrading macOS (and finding something is not working or knowing that some software you need will not work), I suggest a full clone of your drive using Carbon Copy Cloner or Super Duper, making that a fully bootable external drive and then going ahead with whatever you are doing. I have a few external drives to let me boot an old Mac into several versions of OS X and macOS, so that I can go back and use some depreciated software when needed. IMO, this is the BEST way if this is your situation.

If money is tight and another drive is not doable, you could partition the 16TB with enough space to clone your boot drive, use one of those apps to duplicate your boot drive to the new partition and then you will have probably 15TB or so left for normal operations and around 1TB (in the new partition) as a bootable option into the current macOS. The partition could be whatever size your boot drive is now- I'm simply assuming 1TB in this example. Time Machine will basically ignore the partition as if you have a 15TB drive instead, so you can continue using TM for backups but have a way back to an exact copy of your Mac boot drive as it is right now.

With a bootable clone, you can choose that boot drive instead of the one built in to boot into it exactly as you cloned it. For example, I have this for macOS 10.13.6 to hang on to certain software functionality that wouldn't function in 10.14 and newer. I also have an old Snow Leopard backup to be able to use a few pieces of software that need Rosetta 1. I have 1 Mac that can boot into either. So on startup, I can let it boot into the newest macOS as default or override to boot into 10.13.6 or even Snow Leopard. If the latter, it is as if it is a Mac from years ago, with all the files/folders/apps as they were- and worked- on those earlier versions of macOS and OS X.

There are some who talk about this rule of not upgrading macOS until the .3 or .4 update. This approach allows you to take shot at the .0 update when released. If it turns out to be buggy/messy/problematic, you can always go back as long as you have a cloned boot drive with what you consider the last stable release (for your needs). TM backups aren't backing up everything, so it is not the same.

If you've been at this long, you probably have some old, smaller hard drives laying around doing nothing. Boot drives in Macs are usually not very big (would even 1TB be "average"?). You can probably put an old, maybe "retired" (because it is "too small") drive back to work. Else, buying an external to match whatever size you have in your Mac is probably an external that doesn't cost more than $150 at most... and more likely less than $100.
 
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CC88

macrumors 6502
Original poster
Sep 29, 2010
488
117
Dear

thank you very much for answering.

To clarify: I have my work drive that is a 8tb thunderbolt3 raid. In this drive I have a 2tb folder that I want to archive to free up more space on my RAID.

The 16tb TM thunderbolt3 RAID disk is my actual TM disk. I would like to continue to use it in the future for hourly backup. What I want is to lock a specific date so I can revert the 2tb folder above in the future if I need.

I have already copied the 2tb folder on a 4tb usb3 external drive to backup and disconnected the 4tb USB3 disk.

What I want to do is a second backup of this folder in case when I reconnect the 4tb USB3 drive has a fault (maybe after months in off state it can have a fault).

So I thought I can lock a TM backup and than delete the 2tb folder on my 8tb raid.

Another thought was to copy the 2tb folder on the root of TM backup disk (but I don't know if I can create problems creating a folder outside the Backups.backupdb on TM disk).

I think that partitioning the TM Raid is not an option.

Hope all is more clear now. Sorry for misunderstanding.
 

HobeSoundDarryl

macrumors G5
If I'm understanding this right, if the 2TB is what you want to preserve, you only need a second copy of it on something else. You've already made one copy but worry about that drive failing. So add another stick for a second copy. The odds in 2 sticks both failing whenever you need access to those files again must be very long. If you are really nervous, buy 2 more sticks for 3 separate copies. And don't store all of them at the same place to overcome risk of fire/theft/flood.

A 2TB stick is probably $30 or so. Yes, I see many for $25-$40 online.

Once you have maybe 1 or 2 more backups, you can delete the 2TB on the work RAID and let TM continue to work as it does. For a while at least, TM will still have ALL of the files in the 2TB folder on it too (they won't face possible deletion until the TM disc is completely full)... so you would have 2,3 or maybe 4 ways to recover those files for some time into the future... and 2-3 ways to recover them for up to near "forever" even after TM eventually overwrites all of them.

My general advice is always the same for very important files: TWO separate backups with at least one of those stored off site. Odds in losing the files go way down that way. Three is probably overkill but adds even more peace of mind for- what in this case- would cost about $30.
 
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CC88

macrumors 6502
Original poster
Sep 29, 2010
488
117
Thank you very much. I wasn’t aware that a 2tb stick is around $20. This is the solution to have a second copy of my folder.
 

Hombre53

macrumors regular
Feb 27, 2018
246
263
A 2Tb "stick" for $30? Where? My guess (and I'll stand corrected if so) is that the $30 "stick" is a USB2 Chinese knockoff that I wouldn't trust under any circumstances... be careful of cheap, inexpensive Chinese junk solid state electronics. There are no substitutes for quality media when it comes to a backup. JMHO
 
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HobeSoundDarryl

macrumors G5
There's many of them on Amazon... and many have reviews that seem to split at 1 star "junk" and 4-5 "star" fantastic (like seemingly everything else in technology products these days). But yes, they could all be "junk"... as could all of the positive reviews... or maybe vice-versa. A search of the topic does include many links warning about the big storage for cheap scam with USB sticks.

However, up it another $20 and you get into small 2TB hard drives from names like Toshiba, Seagate, Western Digital and similar. I regularly use a 4TB WD external that cost $99 a few years ago. Definitely 4TB and works just fine.

So somewhere in there, it seems OP can get the 2TB they want for a pretty low-cost amount.
 
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CC88

macrumors 6502
Original poster
Sep 29, 2010
488
117
Will take a look. Maybe I can buy one that’s rated higher.
 

KaliYoni

macrumors 68000
Feb 19, 2016
1,785
3,928
I would either use a dedicated drive for the TM backup that needs to be preserved (connect, backup, disconnect, store) or make a clone on its own drive (I use Carbon Copy Cloner for weekly backups that are redundant to my ongoing TM backups).
 
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