Can I use a single external drive to maintain time machine backups for two Mac computers?

Hello
We have an older mac mini and macbook air. I have one Western Digital external USB drive. Can I use the same drive to hold and maintain time machine backups for both machines?
I already have the macbook air time-machined on the WD drive. I now want to backup the mac mini onto the same drive. Is it going to over write the time machine backup or is the software smart enough to maintain two separate files, partitions, whatever it does..?

It will maintain separate backups. Note that it's generally advisable to use separate drives for best practice backup, but yes, it will work for both computers, provided you have enough space (need generally 2-3 times the total used file space for both Macs).
Matt

Similar Messages

I have a mid2009 MacBook Pro for which I have been using a USB WD HD for Time Machine. I'd like to get a wireless HD and start a new Time Machine backup for this Mac and retire the 5 year old WD drive. Can I start over?

I have a mid2009 MacBook Pro running Mavericks for which I have been using a USB WD HD for Time Machine. I'd like to get a wireless HD and start a new Time Machine backup for this Mac and retire the 5 year old WD drive. Can I start over?

no archive/ backup is perfect, HD clones can be set to make incremental additions, same as time machine however, though they are more time involved in doing so.
See the + and - of all data backup/ archives below and "spread it around".... or the "dont put your eggs all in one basket" philosophy.
Peace
Data Storage Platforms; their Drawbacks & Advantages
#1. Time Machine / Time Capsule
Drawbacks:
1. Time Machine is not bootable, if your internal drive fails, you cannot access files or boot from TM directly from the dead computer.
2. Time machine is controlled by complex software, and while you can delve into the TM backup database for specific file(s) extraction, this is not ideal or desirable.
3. Time machine can and does have the potential for many error codes in which data corruption can occur and your important backup files may not be saved correctly, at all, or even damaged. This extra link of failure in placing software between your data and its recovery is a point of risk and failure. A HD clone is not subject to these errors.
4. Time machine mirrors your internal HD, in which cases of data corruption, this corruption can immediately spread to the backup as the two are linked. TM is perpetually connected (or often) to your computer, and corruption spread to corruption, without isolation, which TM lacks (usually), migrating errors or corruption is either automatic or extremely easy to unwittingly do.
5. Time Machine does not keep endless copies of changed or deleted data, and you are often not notified when it deletes them; likewise you may accidently delete files off your computer and this accident is mirrored on TM.
6. Restoring from TM is quite time intensive.
7. TM is a backup and not a data archive, and therefore by definition a low-level security of vital/important data.
8. TM working premise is a “black box” backup of OS, APPS, settings, and vital data that nearly 100% of users never verify until an emergency hits or their computers internal SSD or HD that is corrupt or dead and this is an extremely bad working premise on vital data.
9. Given that data created and stored is growing exponentially, the fact that TM operates as a “store-it-all” backup nexus makes TM inherently incapable to easily backup massive amounts of data, nor is doing so a good idea.
10. TM working premise is a backup of a users system and active working data, and NOT massive amounts of static data, yet most users never take this into consideration, making TM a high-risk locus of data “bloat”.
11. In the case of Time Capsule, wifi data storage is a less than ideal premise given possible wireless data corruption.
12. TM like all HD-based data is subject to ferromagnetic and mechanical failure.
13. *Level-1 security of your vital data.
Advantages:
1. TM is very easy to use either in automatic mode or in 1-click backups.
2. TM is a perfect novice level simplex backup single-layer security save against internal HD failure or corruption.
3. TM can easily provide a seamless no-gap policy of active data that is often not easily capable in HD clones or HD archives (only if the user is lazy is making data saves).
#2. HD archives
Drawbacks:
1. Like all HD-based data is subject to ferromagnetic and mechanical failure.
2. Unless the user ritually copies working active data to HD external archives, then there is a time-gap of potential missing data; as such users must be proactive in archiving data that is being worked on or recently saved or created.
Advantages:
1. Fills the gap left in a week or 2-week-old HD clone, as an example.
2. Simplex no-software data storage that is isolated and autonomous from the computer (in most cases).
3. HD archives are the best idealized storage source for storing huge and multi-terabytes of data.
4. Best-idealized 1st platform redundancy for data protection.
5. *Perfect primary tier and level-2 security of your vital data.
#3. HD clones (see below for full advantages / drawbacks)
Drawbacks:
1. HD clones can be incrementally updated to hourly or daily, however this is time consuming and HD clones are, often, a week or more old, in which case data between today and the most fresh HD clone can and would be lost (however this gap is filled by use of HD archives listed above or by a TM backup).
2. Like all HD-based data is subject to ferromagnetic and mechanical failure.
Advantages:
1. HD clones are the best, quickest way to get back to 100% full operation in mere seconds.
2. Once a HD clone is created, the creation software (Carbon Copy Cloner or SuperDuper) is no longer needed whatsoever, and unlike TM, which requires complex software for its operational transference of data, a HD clone is its own bootable entity.
3. HD clones are unconnected and isolated from recent corruption.
4. HD clones allow a “portable copy” of your computer that you can likewise connect to another same Mac and have all your APPS and data at hand, which is extremely useful.
5. Rather than, as many users do, thinking of a HD clone as a “complimentary backup” to the use of TM, a HD clone is superior to TM both in ease of returning to 100% quickly, and its autonomous nature; while each has its place, TM can and does fill the gap in, say, a 2 week old clone. As an analogy, the HD clone itself is the brick wall of protection, whereas TM can be thought of as the mortar, which will fill any cracks in data on a week, 2-week, or 1-month old HD clone.
6. Best-idealized 2nd platform redundancy for data protection, and 1st level for system restore of your computers internal HD. (Time machine being 2nd level for system restore of the computer’s internal HD).
7. *Level-2 security of your vital data.
HD cloning software options:
1. SuperDuper HD cloning software APP (free)
2. Carbon Copy Cloner APP (will copy the recovery partition as well)
3. Disk utility HD bootable clone.
#4. Online archives
Drawbacks:
1. Subject to server failure or due to non-payment of your hosting account, it can be suspended.
2. Subject, due to lack of security on your part, to being attacked and hacked/erased.
Advantages:
1. In case of house fire, etc. your data is safe.
2. In travels, and propagating files to friends and likewise, a mere link by email is all that is needed and no large media needs to be sent across the net.
3. Online archives are the perfect and best-idealized 3rd platform redundancy for data protection.
4. Supremely useful in data isolation from backups and local archives in being online and offsite for long-distance security in isolation.
5. *Level-1.5 security of your vital data.
#5. DVD professional archival media
Drawbacks:
1. DVD single-layer disks are limited to 4.7Gigabytes of data.
2. DVD media are, given rough handling, prone to scratches and light-degradation if not stored correctly.
Advantages:
1. Archival DVD professional blank media is rated for in excess of 100+ years.
2. DVD is not subject to mechanical breakdown.
3. DVD archival media is not subject to ferromagnetic degradation.
4. DVD archival media correctly sleeved and stored is currently a supreme storage method of archiving vital data.
5. DVD media is once written and therefore free of data corruption if the write is correct.
6. DVD media is the perfect ideal for “freezing” and isolating old copies of data for reference in case newer generations of data become corrupted and an older copy is needed to revert to.
7. Best-idealized 4th platform redundancy for data protection.
8. *Level-3 (highest) security of your vital data.
[*Level-4 data security under development as once-written metallic plates and synthetic sapphire and likewise ultra-long-term data storage]
#6. Cloud based storage
Drawbacks:
1. Cloud storage can only be quasi-possessed.
2. No genuine true security and privacy of data.
3. Should never be considered for vital data storage or especially long-term.
4. *Level-0 security of your vital data.
Advantages:
1. Quick, easy and cheap storage location for simplex files for transfer to keep on hand and yet off the computer.
2. Easy source for small-file data sharing.

How can I restore a single image from an aperture time machine backup, do I have to restore the entire library? that does not make sense

I hope there has been found a more efficiant solution for this, how can I restore a single image from an aperture time machine backup, I really hope I don't have to restore the entire library? that does not make sense
any suggestions?

Did you try browsing your backups in the Finder ? That is, do not go and "Enter Time Machine". Instead, navigate to your Time Machine backup via Finder and then manually go to the time period (by folder name) you are looking for ... when you find your Aperture library you can then "Show Package Contents" and find the Master you are looking for.

External drive storage and Time Machine backup.

I don't want to keep photos on my hard drive anymore as they take up too much disk space.
1. Can the "Pictures" directory that exists on all Macs be assigned a new location on an external drive? ie, I save photos to the "Pictures" directory and they automatically go to the external drive.
2. If I store all my photographs on an external drive can I have Time Machine back them up to another external drive I currently use for backing up my HD? If so, how do I set this up in Time Machine?
Merci buckets!

werdup wrote:
2. If I store all my photographs on an external drive can I have Time Machine back them up to another external drive I currently use for backing up my HD?
Yes, as long as it's formatted for a Mac, and you tell Time Machine to stop excluding it (externals are excluded by default).
If so, how do I set this up in Time Machine?
See Time Machine - Frequently Asked Question #32 for details and considerations.

Problems with Time Machine backup for two machines to one external drive

I have a brand new WD 500GB USB My Book external drive plugged into my Intel Mac Mini running 10.5.1 to use as a TM backup drive (TM reformatted it to HFS+ journaled). The Mini's connected by ethernet to the Airport Extreme. It works great. I setup my wife's MacBook Pro 17" Dual Core 2 w. 10.5.1 for TM using the Mac Mini's TM backup drive and it works fine (a little slower at 811.n wi-fi speeds, but OK). I have the Mac Mini setup in Energy Saver to shut down at night and restart in the morning. The morning after I setup my wife's MacBook Pro for TM I found a big black & white message (in half a dozen languages) on the Mac Mini saying start up failed and I need to reboot using the power button. I did and everything was cool. Now comes the problem, it's done it three days in a row so it looks like there is a problem with the TM setup. It didn't do this before I setup my wife's computer for TM.
Any thoughts on what is causing this? We've had minimal problems with Leopard setup (short of a brief hunt for an Airport Extreme Drive and a couple of network printers during initial setup).

1 mistake @ a time wrote:
I works fine over a network if the TM drive is attached to another Mac running Leopard. It won't work with an Airport drive (Apple deep sixed that feature in the final release).
We have an Airport Extreme base station, and we plan to add an Airport Express to boost the power to reach the second floor. We are ordering 4 iMacs, 20", plus I have the Macbook 13" that I have had for a few months.
We thought we could connect one large external drive via firewire cable to one of the iMacs and use it to back up all five computers via Time Machine.
Is that possible, or does everybody need their own external drive?
Thanks!
susan

External Drive Stolen with Time Machine Back Ups

Hello,
Sorry if this has been posted before. I scanned through a few pages of posts and didn't see anything.
My home was burglarized and they took my G5, Cinema Display and my 500GB external drive with my Time Machine backup data. My question is: How secure is the data on the external drive? Can the theif just plug in the drive and see all of the files or does TM password protected? My G5 was password protected to log in to it. Does that log in transfer to the TM files?
Thanks!
DH

As Donald says, the data can be accessed.
Your backups are as secure (or insecure) as your Mac -- if someone steals either, they can get at your data fairly easily, if they know what they're doing, unless it's encrypted.
It is harder to get at Time Machine backups on an external drive, because Windoze can't read it; you'd have to use a Mac (running Leopard or Snow Leopard) to access it.
But most theft is not for your data; it's to resell the hardware.

Can I use a 2tb external drive with Time Machine to backup my Mac Mini (256gbSSD + 2tbHDD)?

Can I use a 2tb external drive with Time Machine to backup what I have on my Mac Mini?
My Mac Mini has one 256 SSD and one 2tb HDD. I want to use Time Machine to do a backup of everything.
Would an external 2tb My Passport Drive by Western Digital work for the backup?
It seems like it would not work because the total storage on the Mac Mini is 2304 gigabytes (SSD + HDD).
And the external Western Digital drive is only 2048 in gigabytes versus 2304 gigabytes the Mac Mini has.

No. A Time Machine backup drive should have at least twice the capacity of the drive it backs up. You would need at least a 4 TB backup drive for Time Machine.
Might I suggest as an alternative that you not use Time Machine but a third-party backup utility that simply overwrites older files with new ones such that the backup drive can be the same capacity as the drive backed up.
Suggested Backup Software
1. Carbon Copy Cloner
2. Get Backup
3. Deja Vu
4. SuperDuper!
5. Synk Pro
6. Tri-Backup
Others may be found at MacUpdate.
Visit The XLab FAQs and read the FAQ on backup and restore. Also read How to Back Up and Restore Your Files.

Can Time Machine Backup to Two Different Drives?

I have many Apple Computers, and I was wondering if it were possible to have time machine backup to two different drives.
I want it to back up My documents, Mail, and other files/folders that I access often to a partition of my internal drive every minute.
And
I want it to back up Everything on my Mac to my external each night upon connecting it to my mac.
I take my MacBook everywhere with me and I need to make sure that the files I work on the most stay Perfectly Accessible no matter what, and I don't want to sacrifice too much space for that procedure. I would rather just be able to do constant backups of my most used files and folders, and then do a system backup each night to make sure I always have what is needed.

Let me add some more observations. I use two disks, one at home (its a mounted volume on another Mac at home) and the other is a portable disk that I attach to my MBP at work. This works fine.
About your details - TM backs up every hour. If you look around you'll find some posts that give instructions on changing the frequency (I haven't paid attention to these, so I can't help you). However, backing up to another partition on the same drive is not what I'd recommend. If the drive dies, you may lose both partitions.
As for doing constant backups of the most used files and at night doing a system backup - it seems to me you aren't "getting" TM. This sounds like the type of backup strategy one uses with "regular" backup software. I don't think I'd recommend backups every minute, but for short intervals, why not just do a default backup of everything. It doesn't really back up everything, just things that have changed. The only time it does a complete backup is the first time you use it with a specific drive. After that it no longer does complete backups, unless you reformat the drive and start from scratch.

Accidentally converted my external hard drive to a time machine backup

Hi there, got a problem. I accidentally converted my external hard drive to a time machine backup and it re-formats my hard drive. What should i do to get back my data? It happened during my first time using a Mac book Air...
Please help. Thank you.

As Link pointed out in that thread, there's a lot excluded:
Dec 26 12:29:11 Branch-iMac com.apple.backupd[3876]: Backup content size: 340.7 GB excluded items size: 256.3 GB for volume Media Server
Thus there should be about 80 GB that's included.
And part of it WAS backed-up:
Dec 26 15:43:56 Branch-iMac com.apple.backupd[3876]: Copied 3986 files (13.6 GB) from volume Media Server.
He's also shown some things that aren't being backed-up, and suggested a couple of things to do, but you haven't responded to his last post.

HT204053 can I use 2 different apple id's and one itunes id for two seperate I-phones?

can I use 2 different apple id's and one itunes id for two seperate I-phones?

Welcome to the Apple Community.
Yes.

HT4413 What if migration assistant isn't recognizing my external hard drive with my time machine backup on it.

Tech department updated my computer to Lion and wiped it clean. I'm trying to restore my documents/photos/etc from a Snow Leopard time machine backup. When trying to use Migration Manager, when it asks for me to "Select my system," my hard drive with the time machine backup doesn't appear.

See Pondini's TM FAQs for starters.

When I get to the select disk page it says that the HD is uesd as time machine drive. How can I remove time machine backup from my Mac.

I am tring to installe OS X Mavericks. When I get to the select disk page it says that the HD is uesd as time machine drive. How can I remove time machine backup from my Mac.

Open up your Finder and click on Go on the top menu bar. Select Computer and then double click Macintosh HD. In here delete the backup folder. Might be called backups.backupdb.

How to transfer a single Application from an old Time Machine backup

Hi
My old G5 unexpectedly died so i picked up a new iMac. When I set it up I used migration assistant to transfer everything but was told by a Genius not to "check" applications as I would need to re-install any apps that used a key anyway and there may be issues with snow leopard.
Turns out the new machine didn't have Snow Leopard after all and the one key application that I forgot to account for was my Palm Desktop. This of course has all of my addresses etc. and was far more up to date then the handheld which I haven't used in a couple years.
Is there any way to selectively retrieve this application from the Time machine backup for my old G5? I would even be happy if I could just get the data but I have no idea where to even look for it.
Thoughts?
Thanks to any caring sole who thinks they can help
SDK

This is what I would do, if you absolutely had to run the old Palm Desktop app on your new iMac.
The last version of Palm Desktop appears to still be available from palm.com
http://kb.palm.com/wps/portal/kb/common/article/33219_en.html
Note: This is probably an old PowerPC application, so your Intel iMac will be using Rosetta to run it. That is fine, but a window letting you know may pop up if it is the first PowerPC app you have run.
Hopefully, the installer and application will work properly on a new Mac with Leopard or Snow Leopard.
When it sets up the new user, it should create a folder in your user home folder somewhere. I do not know where this will be, but I would look in places like
<user home folder>/Library/
<user home folder>/Library/Application Support/
<user home folder>/Documents/
for a folder with Palm in the name.
If you can find that folder, note where it is located. Connect the Time Machine backup drive from the G5. In Finder, go into the backup folder to the latest date/time folder. You should be able to navigate to that same location and find that same +Palm data+ folder. First, just copy it over to the iMac's Desktop. Once you have it on the iMac, the idea here (with Palm Desktop NOT running) is to replace the new folder it created with the one from the old iMac. When you run Palm Desktop, hopefully, it will use your old data from the iMac G5.
I have not done this myself for Palm Desktop, but this technique works in other similar situations.

Need to reformat hard drive and restore Time Machine backup. What's the safest way to proceed?

I have a Mac desktop, purchased in 2007. We upgraded last year to Snow Leopard. It has been slow for a few days, and yesterday wouldn't go past the gray screen. Tried booting in recovery with no success, same for safe mode. Even tried fsck -fy. Eventually went to the Snow Leopard install disk and tried to repair disk, but got an "Disk Utility can't repair this disk. Back up as many of your files as possible, reformat the disk, and restore your backed-up files" message. I've got Time Machine back ups on an external hard drive, but I want to make sure I do this right and don't make things worse. What steps do I need to take?

In most of the cases, that Disk Utility message means that the hard drive is damaged.
However, you can try to erase the disk and restore the Time Machine backup to see if it works. Follow these steps:
1. Insert the Snow Leopard DVD and press the C key while your Mac is starting.
2. Go to Utilities menu > Disk Utility, select Macintosh HD on the sidebar, go to Erase tab and erase the disk. If there's an error during this step, take the Mac to an Apple Store to get a new hard drive.
3. Close Disk Utility, go to Utilities menu, choose the option to restore a Time Machine backup and follow the steps.
If the computer is slow after doing this, take the Mac to an Apple Store as soon as you can

Is it possible to restore a single deleted note from a time machine backup? If so how?

is it possible to restore a single deleted note from a time machine backup? If so how?

Hi James,
I was able to use VI server to invoke LV 6.1 VI's using LV 7.0 without issue.
After discovering this and mentioning it in a post somewhere, Rolf Kalbermatter indicated that was expected. and I should not be suprised.
So....
Vi Server may help you.
James Mamakos wrote:
Is there a separate place for me to post VIs to be converted? What's a ballpark figure for the maximum file size i could put on to be converted?
Do you know if the LabVIEW developers can/will create a way to overcome this problem rather than having to convert a VI through all the intermediate versions?
To the best of knowledge NO.
For each versino of LV there isw code included that runs behind the scenes when you open a VI from an earleir version which replaces old functions with the new versions. This is called Mutation code. To accomplish its task it has to know everything that changed between version X and Y. Since it is possible to baby step the versions up and the number of user that jump multiple major versions is small, I don't think any effort will go into that work.
THe largest attachment I have managed to upload was 3 or 4 Meg.
Just trying to help,
Ben
Message Edited by Ben on 04-28-2009 08:58 AM
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

Can I use a single external drive to maintain time machine backups for two Mac computers?

Similar Messages

Maybe you are looking for