Will TM just start working on new iMac?

[zowenso]

Hello. I have a 2TB WD external hard drive that I’ve been using for around 6 years on my Mac mini. It’s partitioned for a TM back up. The other partition is for all my photos and video. The partition for the TM is 319.52gb because the hard drive in the Mac mini is 319.21gb.

If I eject the external hard drive from my Mac mini and plug it into my new 2020 iMac, will it just start doing TM back ups or do I have to do something more? I looked at the storage on the new iMac and it’s 250.69gb. Does that mean if the TM partition is for 320gb that I’m ok? Also is there any risk of me losing any photos or videos that I have in the other partition that I store stuff in when I move the ex hard drive from the Mac mini to the iMac?

Thanks for any help.

 

[DeltaMac]

TM keeps track of any changes to your hard drive, both additions and deletions, so can use more space than whatever hard drive you use for a boot drive. The usual rule-of-thumb is to have double the space for your TM backup, that is, double the storage of your boot drive.
Also, if TM runs out of space on the TM backup, it automatically begins to remove the oldest backups.

If you use your TM drive for backups on your new iMac, TM starts a new backup, just for that iMac storage.

 

[Boyd01]

Also is there any risk of me losing any photos or videos that I have in the other partition that I store stuff in when I move the ex hard drive from the Mac mini to the iMac?

Do you have additional backups? There is no way that I would trust a six-year-old hard drive as my only backup. I also would not store anything else on a time machine disk. If this is your only disk, you might want to reconsider the big picture. Personally, I have the following

Continuous Time Machine backups to a dedicated disk on a fileserver
Bootable Carbon Copy Clone on an external SSD
Continuous cloud backups with Backblaze
A variety of old time machine and carbon copy disks from old systems

I have been using Macs since 1985 and have files going back that far. Not going to take any chances losing all of this! Now, you are off to a good start if you're using Time Machine on an external disk (many people don't even have that), but it really isn't enough. I'd suggest buying (at least) two additional external disks. I know this is an extra expense, but ask yourself how important your data is.

Use one of these disks as a new Time Machine disk for your new iMac and use the other one for your photos. Then setup the new Time Machine disk to also backup your photos and don't store anything else on that disk - dedicate it to Time Machine exclusively. Then, just put your old Time Machine disk away somewhere safe and keep it as an archival backup in case you ever need it.

Also consider some form of backup that is stored off-site, such as a cloud service or a separate disk that you store in your office or at a friend/relative's house. Also think about getting another disk for a bootable clone with Carbon Copy or Super Duper. Time Machine is fine, but it's very different from a clone. You must restore from a Time Machine backup before using it and that can be very slow. With a bootable clone, you just plug it in and use it. This would get you back up and running very quickly after a disaster.

Anyway, those are my thoughts. Enjoy your new iMac!

 

[zowenso]

Do you have additional backups? There is no way that I would trust a six-year-old hard drive as my only backup. I also would not store anything else on a time machine disk. If this is your only disk, you might want to reconsider the big picture. Personally, I have the following

Continuous Time Machine backups to a dedicated disk on a fileserver
Bootable Carbon Copy Clone on an external SSD
Continuous cloud backups with Backblaze
A variety of old time machine and carbon copy disks from old systems

I have been using Macs since 1985 and have files going back that far. Not going to take any chances losing all of this! Now, you are off to a good start if you're using Time Machine on an external disk (many people don't even have that), but it really isn't enough. I'd suggest buying (at least) two additional external disks. I know this is an extra expense, but ask yourself how important your data is.

Use one of these disks as a new Time Machine disk for your new iMac and use the other one for your photos. Then setup the new Time Machine disk to also backup your photos and don't store anything else on that disk - dedicate it to Time Machine exclusively. Then, just put your old Time Machine disk away somewhere safe and keep it as an archival backup in case you ever need it.

Also consider some form of backup that is stored off-site, such as a cloud service or a separate disk that you store in your office or at a friend/relative's house. Also think about getting another disk for a bootable clone with Carbon Copy or Super Duper. Time Machine is fine, but it's very different from a clone. You must restore from a Time Machine backup before using it and that can be very slow. With a bootable clone, you just plug it in and use it. This would get you back up and running very quickly after a disaster.

Anyway, those are my thoughts. Enjoy your new iMac!

Thanks so much to both of you for the feedback. Makes a lot of sense. So basically I should buy two new external hard drives. One for TM and one for photos and video. And obviously those will both stay plugged in and on my computer table at all times? I do a lot of photos, so I’d probably get a 2TB ex hd for photos and video. As far as ex hd for the TM back up, that one can be much smaller since it’s just going to be for the TM? If the iMac is 250gb can I just get something like a 500gb external hard drive for the TM back up?

Also, if I wanted to move all my photo and video folders from my current external HD to a new one, is there an easy way to do that or do I just drag one folder at a time from my old external to my new one? Thanks a lot.

 

[Boyd01]

Yes, my suggestion was to get two new disks, however the Time Machine disk needs to be the big one. If you have a 2tb disk for photos and a 256gb internal SSD on the iMac, then you should probably get a 3tb or 4tb Time Machine disk. The idea is to have Time Machine backup EVERYTHING, including your photos (which I assume you would not want to lose). You would need to have the photos disk connected all the time for this to work properly.

You might also consider getting a smaller external 256gb or 512gb SSD, such as a Samsung T5 or similar. Then use Carbon Copy Cloner to periodically clone the internal SSD on your iMac. This would enable you to boot directly from the external SSD if needed. Store this disk separately from your computer, that way you are protected if the computer is stolen or damaged by leaking pipes, etc.

To move the photos to a new hard drive, you could just drag the files with the finder. Or you could use Carbon Copy Cloner for that too. But if you use the Finder, it's not necessary to drag "one folder at a time". Just select ALL of the folders and drag them to the new disk. Since all your photos are on a separate partition, I would lean towards using Carbon Copy to just clone that partition to the new disk. It does better error checking than the Finder and will also probably be faster (from my experience).

 

[russell_314]

Large external drives are pretty cheap nowadays. I just bought a 4 TB Western Digital for $85 as my Time Machine backup drive. Now of course it wont be as fast as an SSD but I'm in no hurry with the backups.

 

[hallux]

Here's my backup -
2 TB Western Digital MyPassport for TM. This drive is close to 8 years old now
Cloud
Original medium (for pictures from "lifetime" trips I keep them on an SD card)

I'm in the process of setting up a NAS (Network Attached Storage), I just ordered the drives I need to fill it out. The NAS can be set up as a TM destination so I'll set aside some space for that.

I also have a CCC backup of my old Mac, before I wiped it to sell.

The end result is that my photos are stored in at least 4 places (Mac, TM backup, cloud backup, SD card), including an off-site (cloud) in case my place burns to the ground, while the rest of my stuff is in 3 places including the cloud.