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#30244 - 06/05/14 07:48 PM Back up advice please
Kate Offline


Registered: 08/18/09
Loc: Australia

MacBook Pro Retina running Mavericks 10.9.3

I am looking for reliable back up software and considering Apple Capsule.

I am the only mac user in our house, while five other people use Windows, so am wondering if I am inviting problems.

We currently use Apple Airport Extreme as a router and it has been problem free, but back up is what I am after.
Is Apple capsule the way to go or, if not, can anyone please recommend reliable, independent backup, preferably bootable ,software.
Kate





Edited by Kate (06/05/14 07:49 PM)

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#30245 - 06/05/14 08:01 PM Re: Back up advice please [Re: Kate]
ryck Offline


Registered: 08/04/09
Loc: Okanagan Valley
I've been using SuperDuper for a few years now and it works well. I back up to a separate drive and, as well as having it as my "in case the worst happens" backup, I also use it to boot from when using maintenance software.


Edited by ryck (06/05/14 08:01 PM)
_________________________
ryck

iMac (Retina 5K, 27", 2017), 3.4 GHz Intel Core i5, 8GB RAM, 2400 MHz DDR4
OS Mojave 10.14.6
Canon MX710 Printer
Epson Perfection V500 Photo Scanner
Time Machine on 1TB LaCie USB-C
Carbon Copy Clone on 500GB OWC Mercury OTG Pro

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#30246 - 06/06/14 02:55 AM Re: Back up advice please [Re: ryck]
jchuzi Online


Registered: 08/04/09
Loc: New York State
I second Ryck's endorsement of SuperDuper. I have four internal drives but you can easily add external drives. One drive is dedicated as a SuperDuper clone, another is devoted to Time Machine, and a third is used for manual backups of files. The fourth, of course, is my boot drive. I have had occasion to use all three backups, depending on the situation. So, I'm glad to have redundancy.

I can also recommend Carbon Copy Cloner although I have not used it in a long time.
_________________________
Jon

OS 10.15.3, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365

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#30247 - 06/06/14 08:34 AM Re: Back up advice please [Re: Kate]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
I have used an Apple Time Capsule for a few years now to back up three Macs and it has been absolutely trouble free. Additionally I have had the occasion to do a complete restore of one machine when its hard drive cratered and I have often retrieved individual data files on any one of the three machines. Building the "time" universe can sometimes take a bit long and that is exacerbated by the time lag on the network, but it just takes a little patience.

Many people like clones and I too have a clone of my system, but to be honest, it tends to get badly out of date and a clone is merely a snapshot in one instance of time whereas the Time Machine backup consists of hundreds or even thousands of instances in time. Far more flexible.

Having PCs on the network should have zero impact on the Time Capsule backups, but I would not attempt to back the PCs up to the Time Capsule. It needs to be pristine Apple.
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#30250 - 06/06/14 11:14 PM Re: Back up advice please [Re: ryck]
Kate Offline


Registered: 08/18/09
Loc: Australia
Thank you.That sounds encouraging, might I ask which separate drive do you use?

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#30251 - 06/06/14 11:18 PM Re: Back up advice please [Re: jchuzi]
Kate Offline


Registered: 08/18/09
Loc: Australia
Thank you, Suggestions regarding SuperDuper sound good.
Mine is a very simple set up but knowing that back ups are all important I want to be as close to bullet proof as I can get.

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#30252 - 06/06/14 11:37 PM Re: Back up advice please [Re: joemikeb]
Kate Offline


Registered: 08/18/09
Loc: Australia
Thank you. You made a good point about the temporary nature of clones, that I hadn’t thought of.
Sharing anything with Window users is not something I encourage; would it be a waste of money to buy the Apple Time Capsule and then use it only for backing up a MacBook Pro Retina?
Pristine Apple rules!

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#30253 - 06/07/14 01:14 AM Re: Back up advice please [Re: Kate]
ryck Offline


Registered: 08/04/09
Loc: Okanagan Valley
Originally Posted By: Kate
….might I ask which separate drive do you use?

Yes. I use a Mercury On-the-Go Pro from Other World Computing. The drive is extremely well built and was simply 'plug it in and it works' - and it has worked flawlessly since. I like the size and I like the fact that it is 'bus powered', which means it does not need to get power from a wall socket - the computer provides it.

I am a careful shopper and had done all the homework prior to purchase, finding that a lot of people recommended Other World Computing not only for their products but also for the quality of their service. When I spent time on the phone with their chat folks, I found they were very informative without being the least bit pushy.
_________________________
ryck

iMac (Retina 5K, 27", 2017), 3.4 GHz Intel Core i5, 8GB RAM, 2400 MHz DDR4
OS Mojave 10.14.6
Canon MX710 Printer
Epson Perfection V500 Photo Scanner
Time Machine on 1TB LaCie USB-C
Carbon Copy Clone on 500GB OWC Mercury OTG Pro

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#30264 - 06/07/14 05:48 PM Re: Back up advice please [Re: ryck]
artie505 Online


Registered: 08/04/09
Just in case Kate's thinking of acting on your post, I'll mention that I just bought an OWC Mercury On-The-Go enclosure, and I had the option of a Pro or non-Pro, the latter being $18 cheaper, and since all the $18 buys is a full, rather than limited, (1 year) warrantee and some software

Intech® SpeedTools Utilities™ OEM (For Mac OS 8.6 - X only)
ProSoft Engineering® Data Backup for Mac OS X v10.2.8 or later
NovaStor NovaBACKUP® for Windows 2000 or later
Carbon Copy Cloner® for Mac OS X 10.4 or later (which, in another place, is not included, so caution before acting will be wise)

I didn't think it was much of an investment and passed.
_________________________
The new Great Equalizer is the SEND button.

In Memory Of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire

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#30265 - 06/07/14 07:10 PM Re: Back up advice please [Re: Kate]
artie505 Online


Registered: 08/04/09
Don't forget that a Time Capsule is no more than a wireless Time Machine implementation; the latter does not require the former.
_________________________
The new Great Equalizer is the SEND button.

In Memory Of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire

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#30266 - 06/07/14 10:55 PM Re: Back up advice please [Re: Kate]
Kate Offline


Registered: 08/18/09
Loc: Australia
Thanks to all who have posted advice and suggestions.
For the now I will use SuperDuper, then reconsider when I have set up my squeaky new MacBookPro Retina.

I am grateful for all you advice and suggestions.
Kate


Edited by Kate (06/07/14 10:56 PM)

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#30298 - 06/11/14 08:23 PM Re: Back up advice please [Re: Kate]
pbGuy Offline


Registered: 08/04/09
Loc: Portland, Oregon
Here's another approach you might consider...

Use a large external, USB (or Thunderbolt) drive partitioned into 2 drives (Disk Utility makes this task simple) - 1 partition can be set up as a Time Machine & 1 for SuperDuper clones. The direct connect will enable really fast backups, and with the TM partition always connected (and the drive On), you'll take advantage of the hourly backups like a Time Capsule (when your MBP Retina isn't in Sleep mode) as well as being able to do periodic clones.

For real safety, you might consider using 2 external drives (both partitioned as above) so you can periodically swap the drives for respective backups. So, if one of the external drive fails, you've got a recent backup. I employ this strategy by swapping my 2d drive once a week (minimally); and by doing so, I rest easy about possible drive failure.
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MBP15 i7 (2017) - 1TB PCIe-SSD - 10.15.3, iPhone X & iPadPro 11 WiFi, Watch4

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#30301 - 06/12/14 07:14 AM Re: Back up advice please [Re: pbGuy]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
Originally Posted By: PBGuy
Use a large external, USB (or Thunderbolt) drive partitioned into 2 drives (Disk Utility makes this task simple) - 1 partition can be set up as a Time Machine & 1 for SuperDuper clones. The direct connect will enable really fast backups, and with the TM partition always connected (and the drive On), you'll take advantage of the hourly backups like a Time Capsule (when your MBP Retina isn't in Sleep mode) as well as being able to do periodic clones.

For real safety, you might consider using 2 external drives (both partitioned as above) so you can periodically swap the drives for respective backups. So, if one of the external drive fails, you've got a recent backup. I employ this strategy by swapping my 2d drive once a week (minimally); and by doing so, I rest easy about possible drive failure.

Apple does not recommend partitioning the Time Machine drive. They want the maximum possible space available to put off the time that files start dropping off the back end of the backup as long as possible.

Swapping out the Time Machine drive defeats the purpose of Time Machine backups because neither of the two copies would ever be complete thus rendering the Time Machine backups essentially useless. If you want a belt and suspenders approach then clone the Time Machine drive on a regular basis and store it in a fire and flood proof environment off premises. By-the-way banks safe deposit boxes may be fireproof, but most are not flood proof.

Perhaps a better alternative would be to regularly (daily?) copy the Time Machine sparse disk image file to an online cloud storage service — or wait until Yosemity (OS X 10.10) is released and store the image on iCloud.
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#30307 - 06/12/14 03:21 PM Re: Back up advice please [Re: joemikeb]
ganbustein Offline


Registered: 08/04/09
Swapping TM drives leaves each one incomplete, but hardly useless. Most of the time, you want to restore from the latest (or at least a very recent) snapshot, and whichever drive is TM's current quickly catches up.

But I use a different approach.

I have four external drives. One is for SuperDuper backups, one is my normal Time Machine backup, and the other two get rotated: one is always onsite, the other offsite.

The rotated drives are also Time Machine backups. Once a week, I tell TM to use the onsite disk for backup, let TM do one backup, then switch TM back to the normal drive. I take the currently onsite drive offsite and bring back the previously offsite drive. I plug it in, and tell TM to do one backup to it before switching TM back to its normal drive.

TM's normal drive is thus always complete. The drives I rotate offsite essentially contain only weekly backups, but those weekly backup go way back.

The time it takes TM to make one of those weekly backups is longer than it takes for a normal backup, but is still much faster than a SuperDuper backup.


Independently of the above, my normal boot disk and the SuperDuper clone of it are actually partitioned into a "normal" and a "emergency" partition. The emergency partition contains only the basic OS plus whatever utilities I might need to do emergency repairs of the normal partition.

I should do SuperDuper backups at least weekly. In practice, I wait for an OS upgrade, and then perform the following steps:
  1. Log out of my normal account into my admin account. Turn on the drive I use for SuperDuper backups.
  2. Use SuperDuper to clone the emergency partition from the internal drive to the external.
  3. Force one last TM backup, then turn TM off.
  4. Boot from the emergency partition of the internal drive.
    This emergency partition is always configured so that TM is off, and Software Update checks only manually. I don't want anything touching any backup volumes or the normal boot volume except at my explicit command. iCloud is configured to not update Photo Stream. (iPhoto is not installed on the emergency volume. iCloud will try to use the helper tool from the normal boot volume, which will later prevent me from unmounting it.)
  5. I use SuperDuper to clone the normal boot partition from the internal to the external.
  6. I eject and turn off the drive I use for SD backups. (I don't want anything, most especially Software Update, touching this drive.).
  7. I unmount the normal boot volume, and run Software Update manually. (Software Update is very aggressive about finding things to update. I want it at this time to update only what little software I have on the emergency partition, so it's necessary to remove any distractions.) I update anything else on the emergency partition that needs updating. (TextWrangler, for example.)
  8. I remount the normal partition and boot from it.
  9. I let Software Update bring the normal partition up to date. (The emergency partition is already up to date, so Software Update will leave it alone.) I update anything else that needs updating. (BBEdit, for example.)
  10. I resume automatic TM backups, log out of my admin account, and log back into my normal account. TM backs up both the normal and the emergency volumes.

That's a lot of steps, but they're all there for a reason.
  • Software updates are occasionally buggy. I have both a full TM snapshot and a SuperDuper clone taken just before any updates. I can always roll back a buggy update.
  • You can never have too many backups. The SD and TM backups are on different drives, so no single hardware failure can take them both out. They're backed up by two different backup utilities, so that a single bug cannot take them both out. The offsite backups ensure that a single house fire or burglary cannot take out all my backups. (If I lose both local backups, I've probably lost the computer as well. It might take me a week to replace it and whatever else I lost, so weekly backups are fine for offsite.)
  • My SD backup drive is turned off most of the time, so it cannot be accidentally modified. It's on only while SD is actually running.
  • SD is never asked to clone a volume that is in use. This is a general maxim. You cannot reliably copy something that is changing. Your current boot volume is always changing, much more that you might believe. Databases use very sophisticated mechanisms (locking, transactions, etc.) to get around this problem. TM goes to extraordinary lengths to mitigate it, because almost by definition TM is always copying a changing system. But neither SuperDuper nor Carbon Copy Cloner are able to do anything about it. If you clone a volume that's changing, the clone may have errors. (Or it may not. Murphy's Law tells you the errors will be there only when they matter.) You will not be notified of these errors; the absence of a warning does not imply the absence of an error. (So, don't write back and say you've been using SD or CCC to clone your running boot volume and never had an error. I'm not interested, and you should not be so convinced you haven't had errors.)
  • I never boot off a backup, not even during an emergency. Once you boot off a backup, it's not a backup anymore. (Booting from a backup is still there as an option, but one to be used only in a dire emergency, and only after satisfying yourself that whatever put you into this situation is not perilous to the backup. It's OK to test your backup procedures by booting into a clone just to be sure you're really making bootable clones, but only as a test. Get back to your normal volume as soon as possible.)
  • TM is off while I'm updating software. I don't want TM to take a snapshot in mid-install. Also, during updates a lot of files are changing. It's more efficient to let TM see those changes as a batch.
  • Software Update on the emergency partition has been configured to not check automatically, and not download in the background. The emergency partition does not contain "normal" apps, only those that I might need in an emergency, but some of those normal apps come from the App Store. Software Update will notice that the versions on other volumes are out of date, and try to update them. I cannot let it update the version on the normal boot volume that SuperDuper is busy cloning it, because then the clone may end up incomplete or inconsistent. I really cannot let it update the version on the clone SD is writing to. SD freaks out when that happens. (Bug report filed.) Software Update cannot distinguish between the normal boot volume and its clone, so it's a crap shoot which one it tries to update.
  • All software updates are done from my admin account. This is critical for the few remaining apps that still ask you to drag-and-drop updates. Drag-and-drop produces copies that are owned by (and modifiable by) whatever user did the update. I take steps to ensure that all such third-party software, and the folders that contain them, are writable only by my admin user or by root. This is less critical than it used to be, now that most apps automatically update using tools (Software Update, for example) that set ownership correctly no matter who runs them, but there are still some that don't. You don't want malware that manages to run as your default non-admin user to be able to burrow deeper into your system, modifying software that your admin user may later run. If you ever do get infected, you need to know that your admin user is not, and can dig you out of the mess.

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#30308 - 06/12/14 04:25 PM Re: Back up advice please [Re: joemikeb]
pbGuy Offline


Registered: 08/04/09
Loc: Portland, Oregon
Let me clarify my partitioning scheme - I use a 1 TB LaCie drive, one partition being 750 GB for my TM backups & the 2d 250 GB partition just for an SD clone. I'm only using about 100 GB (of 500 GB) on my MBP.

So to date (in 2 years), I've still got just over 300 GB of available space (on the TM partition) for my TM backups. 99% of the time, my primary external drive is plugged in and On and my TM mounted (TM is ON is Sys Pref). During most of the time my TM is mounted, my clone partition is dismounted.

When I do a clone - after mounting that partition, I quit all apps and cease all activity until the clone is completed. I usually also Stop TM in Sys Pref before starting the cloning.

When I do any OS X major update (after completing new TM backup & a new clone), I dismount both the TM (as well as turning Off TM in Sys Pref) and clone partitions, and then, disconnect the LaCie drive.

Based upon observing a manual start of my 2d TM (after switching external drives), it appears - since the TM goes into an initial preparing before backup actually begins - that the TM is calculating what it needs to backup since the previous; and as result, it would make sense that upon completion of the most recent backup, the (2d) TM would be capable of a full restore based upon the state of the computer at the time it was made. Is that correct?

[I agree that having all my backups within the same location is contrary to a truely safe strategy involving an offsite storage, but as I'm retired, I've been simply attempting to safeguard against mechanical hard drive failure. If I take a trip, I actually take one of my external drives out of my house.]

...I've actually never done a full restore from a TM (other than using my TM in the update process going from Mountain Lion to Mavericks); in previous emergencies, I've successfully restored from a most recent clone.

A follow-up about cloning and in regards to the name of the clone... Say, one's internal drive is named MBP HD, and cloud based syncing, between devices, is being used (say, using Dropbox for 1Password) for specific apps. Additionally say, one names the clone as - MBP HD 2; and then, a clone restore is completed to the internal drive. Must all sync paths, for apps using sync, be manually renamed to correspond to the original, named path; or post clone-restore, will the respective app-syncs on the newly re-cloned internal drive work fine without intervention other than simple renaming the clone-restored HD back to the original name (in this case, MBP HD)?

Here's a fairly up-to-date site providing usage details about Time Machine: James Pond's TM FAQ
_________________________
MBP15 i7 (2017) - 1TB PCIe-SSD - 10.15.3, iPhone X & iPadPro 11 WiFi, Watch4

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#30316 - 06/13/14 09:56 AM Re: Back up advice please [Re: pbGuy]
tacit Offline


Registered: 08/03/09
Loc: Portland, Oregon, USA
Originally Posted By: pbGuy
For real safety, you might consider using 2 external drives (both partitioned as above) so you can periodically swap the drives for respective backups. So, if one of the external drive fails, you've got a recent backup. I employ this strategy by swapping my 2d drive once a week (minimally); and by doing so, I rest easy about possible drive failure.


The approach I use is something like this--I don't use Time Machine, but I use Carbon Copy Cloner on two rotating external backup drives. I also have two computers, a laptop and a desktop, that I keep mirrored to each other. That means my files always exist in at least 3 and often 4 places, and particularly critical files (copies of a manuscript, for instance) are also backed up onto a cloud server I run as well.

This paid off recently when one of my external drives took a crapper and suddenly started developing bad sector all over. Fortunately, I didn't lose anything. Many decades of owning computers, with more than a few lost files along the way, has made me very cautious.
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#30317 - 06/13/14 12:39 PM Re: Back up advice please [Re: pbGuy]
ganbustein Offline


Registered: 08/04/09
Originally Posted By: pbGuy
When I do a clone - after mounting that partition, I quit all apps and cease all activity until the clone is completed. I usually also Stop TM in Sys Pref before starting the cloning.

You cannot cease all activity. OS X is always updating an astonishing amount of stuff in the background.

I learned this back in the days when I used Retrospect to do my backups. For all its faults, Retrospect had one very nice feature: after calculating what files had changed since the last backup and copying them to the backup, it went back and compared original vs. copy of every file it had copied, and report as copy errors any that did not match. I was appalled at how many files were repeatedly on that list. Not because they were actual mis-copies, but because OS X is constantly updating them even when you think nothing is going on.

I could exclude some of those files from backup, but there were many (my Address Book database, for example) that I really wanted backed up. To get a clean backup, I had to disconnect from the internet and go into half a dozen different applications and temporarily disable features. Then I had to remember to re-enable all those features after the backup. (I cannot remember what feature I had to turn off in Address Book (now called Contacts), but it's normally updating its data every half hour or so even when it's not running. The copy phase of a Retrospect backup took longer than a half hour, so it was always catching this as an improperly backed up file.

The file updates that OS X does in the background are mostly limited to files on the boot volume (Software Update being the main exception now) or to files that don't get cloned anyway (Spotlight index, for example). I finally worked out that the only way to get a clean Retrospect backup was to be booted off a different volume than the one I was trying to back up. (But then, to get a backup of that different volume, I had to have a different Retrospect backup set just for it.)

You absolutely should not be actively using your computer while cloning your boot volume. Odds are, that's enough. It's unlikely that a miscopy caused by copying a file that's being updated in the background is going to bite you. I don't like gambling with my backups, though. I never clone my current boot volume.

Originally Posted By: pbGuy
it would make sense that upon completion of the most recent backup, the (2d) TM would be capable of a full restore based upon the state of the computer at the time it was made. Is that correct?

Yes. Each Time Machine snapshot is complete as of the time it's made. You can use any TM snapshot (including the latest) to restore to exactly the state you were in when TM made the snapshot.

Originally Posted By: pbGuy
...I've actually never done a full restore from a TM (other than using my TM in the update process going from Mountain Lion to Mavericks); in previous emergencies, I've successfully restored from a most recent clone.

A full-disk TM restore is essentially the same experience as when you used Migration Assistant to restore your data from TM. You boot off any other volume (Recovery HD will work, as will the copy of it that TM made on the backup volume.) Use the menu option to restore from TM, and the system will walk you through the steps. The procedure was well thought out. TM will tell you what information it's going to need from you (which backup volume, which snapshot on that volume, which volume you're going to restore onto), then it collects that data, then it reminds you exactly what it's going to do (including the fact that it's going to erase the volume you're restoring onto), and waits for your final OK. Once you give the OK, you can walk away until it's done. Your files will be restored at full disk copy speed. When it's done, it'll ask one final question: do you want to now boot into the volume you just restored?

Originally Posted By: pbGuy
A follow-up about cloning and in regards to the name of the clone... Say, one's internal drive is named MBP HD, and cloud based syncing, between devices, is being used (say, using Dropbox for 1Password) for specific apps. Additionally say, one names the clone as - MBP HD 2; and then, a clone restore is completed to the internal drive. Must all sync paths, for apps using sync, be manually renamed to correspond to the original, named path; or post clone-restore, will the respective app-syncs on the newly re-cloned internal drive work fine without intervention other than simple renaming the clone-restored HD back to the original name (in this case, MBP HD)?

As a general rule, you do not need to update any paths. Apps remember where key files (including files they sync) are in one of three ways: as POSIX paths, as HFS paths, or using aliases. (Symbolic links are based on POSIX paths.) All of these can be either relative or absolute. The relative paths will take care of themselves; they'll be relative to something found one of the first three ways. POSIX paths pointing to files/folders on the boot volume refer to it as "/", so the name of the boot volume never shows up.

HFS paths and aliases do contain the volume name (assuming they're absolute), even if the target is on the boot volume. Some backup software will update aliases based on the boot volume so that their copies will be aliases based on the clone. But they can only catch the aliases stored in alias files. Aliases and HFS paths stored in preference files and such-like won't get caught, and will still point back to the original disk.

But when you clone again to restore your original disk, and give it the original name, it all comes out right. Aliases that were updated during the original clone will be updated again during the restore. Either way, anything that pointed to the original disk will now point to its restored copy.

One way you can get into trouble is if, when you restore, you don't give the restored disk the same name it had before. Absolute HFS paths and absolute aliases won't find the restored disk. (That is, if you back up by cloning "MBP HD" to "MBP HD 2", and then restore by cloning "MBP HD 2" to "Restored MPB HD", you may find apps still looking for "MBP HD" and not finding it. You should restore by cloning "MBP HD 2" back to a possibly reformatted disk "MPB HD".)

The other way you can get into trouble is by booting off the clone. Some apps will find the files they want to update on the "boot volume" (or relative to something on it, like your home folder), which is now "MBP HD 2", but others will continue looking for and updating them on "MBP HD", because they use absolute HFS paths or aliases. When you later restore by cloning "MBP HD 2" back to "MBP HD", all those changes will be lost. This is another reason why I advise never to boot off your clone (except maybe once to verify your backup procedure, but you should then consider that backup suspect, and make another).

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#30328 - 06/14/14 09:26 AM Re: Back up advice please [Re: ganbustein]
Ira L Online


Registered: 08/13/09
Loc: California
Originally Posted By: ganbustein
or to files that don't get cloned anyway (Spotlight index, for example)


Are you saying that all cloning software bypasses the Spotlight index? Is that a feature built into the cloning software or a characteristic of the System?

There actually seems to be an Applescript created just for the purpose of not creating a new Spotlight index on the destination disk of a clone, presumably so that the cloned version is used??
_________________________
On a Mac since 1984.
Currently: 27" iMacs, Macbook Air, macOS 10.15.x,; iPhones, iPods and iPads galore!

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#30332 - 06/14/14 12:43 PM Re: Back up advice please [Re: Ira L]
ganbustein Offline


Registered: 08/04/09
Originally Posted By: Ira L
Are you saying that all cloning software bypasses the Spotlight index? Is that a feature built into the cloning software or a characteristic of the System?

I won't go so far as to say that all cloning software does bypass the Spotlight index.

Indeed, a sector-level clone (dd, asr, etc.) copies everything, including the Spotlight index, the catalog, and any catalog damage. I do not recommend a sector-level copy except in very specific circumstances. (For example, if you know the catalog is bad, and you're about to attempt repair, but you're concerned the repair may make things worse, you should make a sector-level copy first.)

But a file-level copy should bypass the Spotlight index. After cloning volume A onto volume B, you want the Spotlight index on volume B to tell you about files on B. It should not be telling you about files on A.

If, as I suspect, the Spotlight index tracks files by their file ID (aka inode number) and/or the directory ID (aka inode number) of the parent directory, then copying a Spotlight index to another volume would produce a useless mishmash. (inode numbers are volume-specific. They are not preserved in a file-level copy.) Even if it doesn't, a copied Spotlight index would be incorrect unless both volumes had exactly the same files. That is, if the clone skips any files, or ignores any extra files on the destination, it must skip the Spotlight index.

There's the additional problem that you don't want Spotlight to be indexing files on B while you're copying lots of files to B. As the copy progresses, immediately after each file gets copied, Spotlight would try to index it, which requires the heads to move to that file so it can be read. Then Spotlight wants to move the disk heads to wherever the Spotlight index is, to write what information it has gleaned. Meanwhile, the clone operation wants to move the disk heads to wherever it's writing the next file. This contention dramatically slows down the clone operation, often by orders of magnitude. The drive spends much more time moving the heads than it does reading or writing. Additionally, moving the heads generates heat, so the drive can get very hot. (Neither Spotlight nor any other software actually knows where the heads are, of course, but not knowing about the contention doesn't make it go away.)

What you want to do, before copying A to B, is temporarily turn off Spotlight indexing on B, copy whatever you're going to copy, and then turn Spotlight indexing of B back on (if it was on previously). Spotlight will use the FSEventLog to quickly locate and index the new files, basking in its now unfettered access to the drive heads.

Not coincidentally, both SuperDuper and Time Machine do just that. I assume Carbon Copy Cloner does too (unless it decides to do a sector copy). rsync does not. If you use rsync in a situation where you know it will (or may) copy a large number of files, you should consider adding these Spotlight-befriending steps to your workflow.

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#30350 - 06/16/14 09:33 AM Re: Back up advice please [Re: ganbustein]
Ira L Online


Registered: 08/13/09
Loc: California
Originally Posted By: ganbustein
But a file-level copy should bypass the Spotlight index. After cloning volume A onto volume B, you want the Spotlight index on volume B to tell you about files on B. It should not be telling you about files on A.


A good explanation all around. Thank you for that.

If indeed it is a clone (not sector level) then everything on B is what was on A and a cloned Spotlight index would be an accurate reflection of B and not a problem. What happens next depends on whether the clone is left mounted and can be indexed or ejected.

Quote:
There's the additional problem that you don't want Spotlight to be indexing files on B while you're copying lots of files to B. As the copy progresses, immediately after each file gets copied, Spotlight would try to index it, which requires the heads to move to that file so it can be read. Then Spotlight wants to move the disk heads to wherever the Spotlight index is, to write what information it has gleaned. Meanwhile, the clone operation wants to move the disk heads to wherever it's writing the next file. This contention dramatically slows down the clone operation, often by orders of magnitude. The drive spends much more time moving the heads than it does reading or writing. Additionally, moving the heads generates heat, so the drive can get very hot. (Neither Spotlight nor any other software actually knows where the heads are, of course, but not knowing about the contention doesn't make it go away.)

What you want to do, before copying A to B, is temporarily turn off Spotlight indexing on B, copy whatever you're going to copy, and then turn Spotlight indexing of B back on (if it was on previously). Spotlight will use the FSEventLog to quickly locate and index the new files, basking in its now unfettered access to the drive heads.


I suspect this is the purpose of the Applescript I referenced in my post above and your reasoning supports the need to turn off the idexing during the process.

Thanks again.
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#30376 - 06/21/14 07:20 PM Re: Back up advice please [Re: Ira L]
slolerner Offline


Registered: 08/25/09
Loc: New York City
I use Silverlining instead of SuperDuper. Is there a difference?
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#30382 - 06/22/14 11:36 AM Re: Back up advice please [Re: slolerner]
MikeS Offline


Registered: 08/04/09
I have a very similar set up to yours and use Silverlining - have done for many years - and have never had a problem.

I think Silverlining is super-duper. shocked

Don't know if this is of any significance to this item though. blush

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#30387 - 06/24/14 01:44 PM Re: Back up advice please [Re: MikeS]
tacit Offline


Registered: 08/03/09
Loc: Portland, Oregon, USA
My understanding is Silverlining isn't compatible with OS X Mavericks (or later) and likely never will be.
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