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Mac OS X 10.5 Leopard's Time Machine

What about using a RAID as the BUD?

Can the Time Machine Backup disk (BUD), be a RAID instead of a single physical disk?

If I am going to set something like this TM, I may want to get a mini and connect a bunch of external drives and create a Raid 0 and Raid 1 set or maybe a raid 5 but do not think apple supports it.

Can I use a raid like that as the BUD?
 
Multimedia said:
Wow what an advanced concept. :rolleyes:
Click to expand...

You know I'm pretty excited about this. I don't make regular backups, but I'd like to. No one else has given me a way this intuitive, so yeah, I think it's pretty advanced.

As a software developer, I'm really excited about the hourly backups. It gives me versioning without have to set anything up :).
 
EagerDragon said:
Can the Time Machine Backup disk (BUD), be a RAID instead of a single physical disk?

If I am going to set something like this TM, I may want to get a mini and connect a bunch of external drives and create a Raid 0 and Raid 1 set or maybe a raid 5 but do not think apple supports it.

Can I use a raid like that as the BUD?
Click to expand...
I've never seen a RAID done of individual external drives attached through firewire/usb. That's a scary concept, I wouldn't touch. If you're really that interested in RAID, use a SAN, one of those drive cages, or setup your own server.
 
I'm looking forward to TM, but I have a question.

does anyone know what happens if I delete something that I want to stay deleted, no matter what? Say someone sends me some stupid email jokes or worse, pictures, or I want to erase all history of my association with a certain political organization before the Stasi arrives to seize my hard drives, or I simply don't want to waste backup space on something that I am certain I will never, ever need?

And this is more complex than just "telling TM what to back up when you set it up". I'm talking about, on the fly, day to day, make this file vanish from present and past, forever. This email is spam or some stupid 4 meg video sent by someone who hasn't learned about Youtube, or it's a 50-slide powerpoint that wasn't funny, and i don't want it using up my valuable archive space, and I don't want Big Brother to be able to find it either.

Can Time Machine manage this or do i have to go through and delete all the hard links?
 
chrisgeleven said:
I imagine the best way to handle that is get an Airport Extreme or similar router and plug your external HD directly into it.

That way, your laptop would do its time machien backup when you are home and on your wireless network.
Click to expand...

True for when I am at home, but 70% of my usage happens away from the friendly confines. (and not Wrigley Field)
 
Does anyone know the ratio of Back-up Space to Actual Space Time Machine is going to require - ie. I have 750 gig iMac, should I have a 750 external?
 
ltcol266845 said:
I am curious to see TM usage when working on a Laptop. I have a MacBook Pro which only attaches to an external storage once and a while. I work on the go, in different places like work, school or even a coffee shop. How protected are my files then? If I delete something while I am at school, is it gone? Do these backups only happen when I plug in my external hard drive at home? Or are these backups stored on my laptop until they can be dumped onto my external drive at home?
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Judging from what it says in the article, that these backups are created based on system software that keeps track of differences, it sounds like it would back up whenever connected to a drive with whatever differences have occurred between then and when you last backed up. I don't think it could possibly keep track of changes to individual files on an hourly basis while you're not hooked up to an external, only because that would require the "old" data to be saved on the local hard drive and then transfered to the external later. This would be much more potentially possible if Leopard were running ZFS and you could save only the small bites and bits that had changed locally instead of re-writing whole files if only a small part of them had changed. These kind of small changes could potentially be catalogued locally and then moved to an external drive, assuming you have a certain amount of open space on the internal drive you were willing to sacrifice until your next "sync."

But from the sound of things, yes, this sounds like it's aimed more towards desktop users for the full-featured nature of the beast, but it still offers a very convenient, OS-level way to back up your files even if you're on a laptop.

Anyone think that Apple is potentially considering shipping computers with a secondary, "hidden" drive (possibly flash-based) that could hold if not all of your back-ups, then at least the changes to files that have occurred between backup "sync"s? I could see them doing this as a way of making the backup issue transparent to the laptop user, especially after ZFS is implemented (even though it would seem to go against the basic "data pooling" nature of ZFS).
 
zedsdead said:
Does anyone know the ratio of Back-up Space to Actual Space Time Machine is going to require - ie. I have 750 gig iMac, should I have a 750 external?
Click to expand...

I believe Time Machine will use what it can. So if you have a 750 gig internal and a 750 gig external, it just simply won't keep a history.

Of course you probably don't have all 750 gigs filled up.

I, myself, have a 250 gig iMac, 160 external, 40 gig iBook and 100 gig MBP (in my household) that I plan on shoving into a 1 terabyte drive. None of those disks are full.
 
BrianMojo said:
Anyone think that Apple is potentially considering shipping computers with a secondary, "hidden" drive (possibly flash-based) that could hold if not all of your back-ups, then at least the changes to files that have occurred between backup "sync"s?
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no they are not otherwise someone would have found it while dissasembling their computer. and why can people not understand that Time Machine has nothing to do with ZFS.
 
Orng said:
does anyone know what happens if I delete something that I want to stay deleted, no matter what? ...Can Time Machine manage this or do i have to go through and delete all the hard links?
Click to expand...

That's a very, very good question. And if it's not a feature yet, I'm sure people will be clamoring for it soon enough.
 
overcast said:
I've never seen a RAID done of individual external drives attached through firewire/usb. That's a scary concept, I wouldn't touch. If you're really that interested in RAID, use a SAN, one of those drive cages, or setup your own server.
Click to expand...

DiskUtility lets you take several disks, format them and combine them as 2 raid 0, then again combine them as raid 1. This capability been there for a while, I am just not sure if TM can use it.
 
mrkramer said:
no they are not otherwise someone would have found it while dissasembling their computer. and why can people not understand that Time Machine has nothing to do with ZFS.
Click to expand...

Er, you missed the words "potentially" and "considering." And you don't understand that it has everything to do with ZFS: Right now it has nothing to do with it, sure, but everyone sees the potential and Apple would have to be blind not to see it too, considering Time Machine seems to be set up in a way that will be perfect to implement via ZFS once the file system switches over.
 
Raids for TM

Anyone knows if TM can use a software raid (raid 0 and 1) created by DiskUtility as the target disk to hold the TM backups?

Would be nice to have a 2 terabyte mirror set:
1) Would take a while to fill
2) Would allow me to repair a bad drive and recover from the hardware failure.

Thinking of doing this with a mini, and pointing TM from the other systems to the raid.
 
I brought a Buffalo Linkstation 500GB several months ago in preparation for this very application, (before Leopard got delayed :eek: ).

It links to our office network via ethernet. Now on reading the FAQ, I am completely confused as to whether it will work with TM or not.

I don't mind dedicating the whole drive to TM, but according to the FAQ,

7a) When Apple say backed up to a server do they just mean any network storage?
No, It must be a server or drive. It cannot just a remote drive on the network as 10.5 still sees the remote drive as a folder AFP mount.
Click to expand...

But Question 9 says:

"It will work with any non-bootable volume formatted in Apple’s HFS Extended format. That drive can be stowed inside a Mac Pro, attached on the end of a FireWire or USB cable, or even mounted on your desktop from elsewhere on your network."
Click to expand...

So will it work with a Buffalo Linkstation or not? These network drives seem to be quite popular with Apple users, which is one reason why I brought one.

Call me stupid, but I don't understand the terminology here. Q7 says it won't work with a remote drive on the network, but Q9 says it will work with a drive mounted from elsewhere on the network. It's not clear.
 
What I'm curious about is whether Time Machine does anything to protect against bit rot. Does it checksum the files so it can tell if the backup (or original) is corrupted, or does it just keep a series of links to the corrupted file as though nothing happened? My fear is that one of my pictures gets corrupted and I'll never know until I try to open it. The corruption won't show up in FSEvents, because it wasn't intentional.

ZFS has a mechanism to handle this, so if it's not in TM now, I hope to see it soon.

Lepton said:
Time machine makes regular copies of the files it backs up - it doesn't compress them. And if you have a large file and make one tiny change, the whole file is re-backed up. The advantage is, you can look through the archives yourself if you want to and just drag a backup onto your regular disk to get it back. The disadvantage is the space it takes.

In the future, I believe Apple will address this issue of it making a backup of full, uncompressed files, even when the files have only changed a teensy bit. Remember the fuss over this new ZFS file system? Once fully implemented, it can do proper, partial backups of files with no extra overhead. Once that ability is in Leopard, obviously we will see it going straight into Time Machine. If a huge file like a database gets a teenly little change, only that teeny part will need to be backed up, rather than making a new full backup copy of the file. ZFS also lets you add new hard disks to the backup pool on the fly. ZFS and Time Machine go hand in glove. I'm sure we will see Time Machine making huge gains once ZFS gets into OSX. My guess is it will happen way before OSX 10.6.
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This is very similar to how Network Appliances does it's snapshots. We used this at work for a while and the whole backup system crashed and burned because we were re-generating multi-GB binary files several times a day. Didn't take long before all those snapshots choked the NAS.

ZFS isn't really a complete answer to this problem. It's a help, but not an answer. Imagine you store your data in encrypted format-- change one byte of that file and the whole file contents change. I believe ZFS snapshots at the block level, so simply inserting a byte in the middle of an unecrypted file will shift all of the data in all of the blocks, forcing a full copy to be made. I'm not an expert in ZFS though, so they might be smarter than this but I'm not sure how you could be unless the snapshots are done at the byte level.

The solution Apple has been pushing ever since Spotlight is to avoid monolithic files. Break your data into a bundle of many small files-- so only small parts of the bundle change. In user space, this still looks like a single entity, but in file system space it's a full directory structure. This is how iLife and iWork operate. Not everything can be atomized this way, but if you think about the data structure for a while you can usually find a way.
 
TM will definitely work on a partition on a network drive. Whether it will work in a folder on a partition is open to conjecture, one of the earlier betas did by using a sparse bundle but if that makes it to the final release who knows.(haven't tried with 559)
 
pgwalsh said:
.. Will it makes it unnecessary to have a mirror raid?
.
Click to expand...


Do you want to protect your self from a hardware failure of the Time Machine disk drive? If so then you might want to use a mirror or other RAID for Time Machine

Also your Time Machine backup drive needs to be a bit larger then all the other drives on all the Macs that you need to backup. You might want to use a RAID5 setup
 
EagerDragon said:
Anyone knows if TM can use a software raid (raid 0 and 1) created by DiskUtility as the target disk to hold the TM backups?

Would be nice to have a 2 terabyte mirror set:
1) Would take a while to fill
2) Would allow me to repair a bad drive and recover from the hardware failure.

Thinking of doing this with a mini, and pointing TM from the other systems to the raid.
Click to expand...
If you can actually create a RAID of external harddrives there is no reason TM can not use it. As far as the OS and TM is concerned, RAID is a single drive.
 
BrianMojo said:
That's a very, very good question. And if it's not a feature yet, I'm sure people will be clamoring for it soon enough.
Click to expand...

I'm sure some smart developer will create "iShredder" to get rid of those files that you don't need to save, but would cause problems if your backup drive was stolen and fell into nefarious hands.

Imagine a well meaning mother sending her son a credit card number or bank access info via email, so he can buy some books for classes. Yeah, I know, BAD mom! but being a smart kid, the son deletes the email. He should have a way of saying, okay, we don't want this email archived on a stealable HD.
 
Orng said:
Imagine a well meaning mother sending her son a credit card number or bank access info via email, so he can buy some books for classes. Yeah, I know, BAD mom! but being a smart kid, the son deletes the email. He should have a way of saying, okay, we don't want this email archived on a stealable HD.
Click to expand...

You can tell Time machine to encrypt the entire backup drive. This would solve this problem.

Knowing now, how TM stores data it would be easy to write a one line shell script to track down and kill all copies of a file. (See the man page for "find") It is not hard to put a simple point and click GUI around "find" for those who can't use keyboards. So technically easy to do but what needs to be done is to build this feature into the Finder. Maybe Apple needs to build a "shedder" application and attach it to the right click menu so you could "right click -> shred a file"
 
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