Time Machine: Spit!!!
in [UK Mac]
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From: T i m on 24 Nov 2009 08:11 On Tue, 24 Nov 2009 12:58:42 +0000, Tim Streater <timstreater(a)waitrose.com> wrote: >>> Not so much in my case because all those drives are run through an APC >>> battery backup. >> >> Is that an on-line or off-line UPS Tim? > >Online (I guess). It's an APC ES 550, with 4 sockets which have battery >power when needed, and 4 which are merely protected. I decided to get >this as the power here is occasionally flaky (not so much since though). Dad managed to persuade the Electricity Co who were randomly taking the power away from his house for a week or so to provide him one. ;-) > >> Have you tried simulating a power failure with it doing a TB backup? >> If you haven't please don't just on my behalf). ;-) > >If I unplug it from the all then it starts to beep but everything >continues to run (well, I don't have the ADSL router or network switch >connected through it. Just the Mini and external drives). It then gives >about 20 mins run-time. Sweet, that's a good enough test then. I once saw someone test a UPS by turning it off at the front <blush>. Cheers, T i m
From: zoara on 24 Nov 2009 09:05 T i m <news(a)spaced.me.uk> wrote: > On Tue, 24 Nov 2009 11:50:32 +0000, Jim <jim(a)magrathea.plus.com> > wrote: > > >On 2009-11-24, T i m <news(a)spaced.me.uk> wrote: > >> > >> And understand that leaving your backup 'on-line' also has risks.If > >> you were to leave your TM drive (and I assume that would have to be > >> external to be of any real value), connected to the computer and > > > mains > >> power in between cycles then you could lose your computer and all > > > 57 > >> backups in one foul swoop? ;-( > > > >Time Machine[0] only mounts the drive during backup and restore > > operations. > >During the rest of the time the drive/share is unmounted, so at much > > less > >risk of corruption during power cycles. > > Ok and in a 'files' sense then. It is still vulnerable from a mains > spike taking out the hardware at any time and (to a much lesser > degree) the files during what may even be an unneeded backup cycle > (ie, there may not be anything of importance to back up). If you are worried about this sort of thing then just unplug the drive when you aren't backing up. Your arguments seem to be straw men; the chance of losing data on a time machine drive due to a power spike is far lower than losing data because the ClickFree either didn't back it up or overwrote the good backup with a bad copy (as in the weekly file scenario I outlined). -zoara- -- email: nettid1 at fastmail dot fm
From: Andy Hewitt on 24 Nov 2009 09:24 T i m <news(a)spaced.me.uk> wrote: > On Sat, 21 Nov 2009 22:11:02 +0000, thewildrover(a)me.com (Andy Hewitt) > wrote: > > >One thing to consider as a possibility is the chance of copying a > >corrupt file into a backup. With the types that overwrite existing > >files, this is a very high possibility, and means you could easily copy > >a corrupt file at the time of an imminent system failure. > > Of course (so you will have lost nothing in that instance) but none of > that is what this ClickFree solution is all about (and this isn't > particularly to you). ;-) > > 1) It provides a hands off provision of 'a backup' [1] where one might > not otherwise be done at all. If you wanted a history of backups then > there is nothing stopping you copying the backup folder onto another > drive / computer or simply renaming the folder, forcing a fresh backup > next time. All too complicated for a std user though. Also, how big > might a backup drive need to be to *guarantee* you weren't carrying a > corrupt backup file with a first in first out overwrite system (like > TM)? [2] Oh indeed, it's the 'how long's a bit of string' question. All you can do is minimise the risks. > 2) The backup media is (typically) disconnected once the backup is > complete so no chance of a power surge destroying computer AND backup > hardware / data. [2] Ok, although, as I understand it, a laptop's PSU and battery should act as a buffer, and protect the main system anyway. If I ever do get an iMac, I'd probably get a UPS as well. > 3) Because of it's portability (and the fact that it's *normally > disconnected*) it is easier to take > leave off site. [2] No less with TM though. You can unplug that anytime you like, with a current backup, and put somewhere offsite. As soon as you plug it in again, the backups get updated automatically. > 4) It's faster than a complete (system) backup and a system backup > would be little use to most std users. Possibly. I've had the odd time when I screwed up, and simply cloned back my complete system to get up and running in a short time. > 5) It also lends itself to being used as a portable data drive (rather > than backup per-se). For sure, but so does TM in that context, it can be accessible from any Mac. > eg. Mate runs garage. He uses Sage for his accounts and the old > Windows 3.1 'Cardfile' for his phone book,vehicle history and a couple > of others.[3] He also types the odd document and saves the odd > vehicle related picture. As he's about to finish for the night he > plugs in his ClickFree drive and it automatically copies all new / > modified files to the drive and he puts the drive in his pocket. When > he gets home he can 'restore' any / all of his data to his home PC for > extra access (He can't use Macs as many of the apps he uses are > Windows only, like the Autodata CD's [4]). <pedantry> He could use a Mac (using Windows on it), just not Mac OS </pedantry> > Simples. ;-) Hmm, it is, but using it that way, I certainly still wouldn't consider it as a sole backup solution. > Did you read Elliott's proposed final solution for his backup? No. > Cheers, T i m > > > [1] And we are particularly talking Windows / non TM here, since I > found out the Mac use was far too restricted. Plus, it's probably that > 'Mac users' are a) actually going to be producing 'data' and b) more > likely to understand the risks and already doing something about it. > > [2] Better to have access to a reasonable backup than no access to a > perfect one. They are the only choices for many. That's a consideration, yes. > [3] I wrote him a little batch file that copies said Cardfile > data-files to the daily_pen_drive_backup_system I instigated for him a > while back. There is a very good chance he doesn't use it, not because > he would like to lose his data but because the effort isn't worth the > perceived (and proven to be 'nil' over many years so far) risk. OK, I really don't see the difference here, other than perhaps a pen-drive might be considered more volatile as a backup media. > [4] Windows 2000, XP or Vista. Microsoft Internet Explorer 5.5 > upwards. > > http://www.autodata.ltd.uk/technical-specifications.asp Understandably, most of the motor trade is technologically decades behind the rest of the world. In many cases garage systems have only moved to Windows in the last few years (seriously). Over the last 30 years I've used systems running on, well, firstly a proprietry system, then Xenix, and Unix. We only moved to a Windows based system in about 2003, and indeed there was only one serious Dealer Management System that did run on Windows up to then. -- Andy Hewitt <http://web.me.com/andrewhewitt1/>
From: T i m on 24 Nov 2009 10:03 On Tue, 24 Nov 2009 14:24:21 +0000, thewildrover(a)me.com (Andy Hewitt) wrote: >> 2) The backup media is (typically) disconnected once the backup is >> complete so no chance of a power surge destroying computer AND backup >> hardware / data. [2] > >Ok, although, as I understand it, a laptop's PSU and battery should act >as a buffer, and protect the main system anyway. Yep (should). >If I ever do get an >iMac, I'd probably get a UPS as well. I've probably got half a dozen kicking around here in varying sizes (mainly APC but also a couple of MG units) and I considered re-batterying one and sticking it on. However, I'm not sure the extra energy it might consume or the space it would take up would equal the very rare time we get power issues here (although I could be speaking too soon etc) and their consequences. <fingers crossed> > >> 3) Because of it's portability (and the fact that it's *normally >> disconnected*) it is easier to take > leave off site. [2] > >No less with TM though. You can unplug that anytime you like, with a >current backup, and put somewhere offsite. As soon as you plug it in >again, the backups get updated automatically. Indeed, but if the point of TM (specifically over this dongle or the drive) is that it can take regular / historic type backups so the tendency would be to leave it on wouldn't it? > >> 4) It's faster than a complete (system) backup and a system backup >> would be little use to most std users. > >Possibly. I've had the odd time when I screwed up, and simply cloned >back my complete system to get up and running in a short time. You did because you could. They wouldn't know where to start (generically). > >> 5) It also lends itself to being used as a portable data drive (rather >> than backup per-se). > >For sure, but so does TM in that context, it can be accessible from any >Mac. I meant more because of the concept of it being 'plugged in when needed' rather than typically being 'left on all the time and removable'. Think of it like tank mixing 2/ V autolube (this ClickFree being the pre/ tank mix). With one the oil is in yer pannier and used when needed. With the other it's in the oil tank and used / available on demand. The tank can run out if not checked regularly and you can suffer damage (all be it completely predictably, as Elliott found out). With tank mix you put the oil in as you put in the petrol (if you remember) and whilst it might not be as accurate it's pretty obvious that it's going on and where the oil is (and if you crash the bike your oil might not pour all over the road as easily). ;-) > > ><pedantry> He could use a Mac (using Windows on it), just not Mac OS ></pedantry> True, he could, but it's bad enough to get him to do a backup of his own (valuable) data! > >> Simples. ;-) > >Hmm, it is, but using it that way, I certainly still wouldn't consider >it as a sole backup solution. Nor me, but yep, versus no backup solution it's great. ;-) > >> Did you read Elliott's proposed final solution for his backup? > >No. Ah, worth a read (seriously). >> [3] I wrote him a little batch file that copies said Cardfile >> data-files to the daily_pen_drive_backup_system I instigated for him a >> while back. There is a very good chance he doesn't use it, not because >> he would like to lose his data but because the effort isn't worth the >> perceived (and proven to be 'nil' over many years so far) risk. > >OK, I really don't see the difference here, other than perhaps a >pen-drive might be considered more volatile as a backup media. Because my batch file *just* copies a few fairly specific files from one directory (well, it uses a bit of a wildcard but only for the file names), not scans the entire machine for over '400 file types'. > >> [4] Windows 2000, XP or Vista. Microsoft Internet Explorer 5.5 >> upwards. >> >> http://www.autodata.ltd.uk/technical-specifications.asp > >Understandably, most of the motor trade is technologically decades >behind the rest of the world. So being in advance technologically may not be a good thing in this case. I built the PC for him a few years back out of bits n bobs and he's happy enough with it. ;-) > In many cases garage systems have only >moved to Windows in the last few years (seriously). He's been ahead of the pack then, running Windows 3.1 a good 10 years ago. ;-) > Over the last 30 >years I've used systems running on, well, firstly a proprietry system, >then Xenix, and Unix. We only moved to a Windows based system in about >2003, and indeed there was only one serious Dealer Management System >that did run on Windows up to then. And now it seems many of them do (BMW Diagnostics, the Suntune systems are two for sure). And the John Deere forward harvesters as I found out previously. ;-) Cheers, T i m
From: Andy Hewitt on 24 Nov 2009 10:40
T i m <news(a)spaced.me.uk> wrote: > On Tue, 24 Nov 2009 14:24:21 +0000, thewildrover(a)me.com (Andy Hewitt) > wrote: [..] > >No less with TM though. You can unplug that anytime you like, with a > >current backup, and put somewhere offsite. As soon as you plug it in > >again, the backups get updated automatically. > > Indeed, but if the point of TM (specifically over this dongle or the > drive) is that it can take regular / historic type backups so the > tendency would be to leave it on wouldn't it? Indeed, that is the whole idea. Nothing stopping you plugging in as you come into work and disconnecting it and taking it home at the end of day. Homers have a different problem of course, and probably don't have two locations they could easily, and regularly, take the drive unit to, so will end up staying put. Mine does, although it is in a steel cased PC tower. > >> 4) It's faster than a complete (system) backup and a system backup > >> would be little use to most std users. > > > >Possibly. I've had the odd time when I screwed up, and simply cloned > >back my complete system to get up and running in a short time. > > You did because you could. They wouldn't know where to start > (generically). Yes, and I've been able to do it for family too. Leaving them with Super Duper running, I have been able to restore them to a reasonable point quite easily. > >> 5) It also lends itself to being used as a portable data drive (rather > >> than backup per-se). > > > >For sure, but so does TM in that context, it can be accessible from any > >Mac. > > I meant more because of the concept of it being 'plugged in when > needed' rather than typically being 'left on all the time and > removable'. Think of it like tank mixing 2/ V autolube (this ClickFree > being the pre/ tank mix). With one the oil is in yer pannier and used > when needed. With the other it's in the oil tank and used / available > on demand. The tank can run out if not checked regularly and you can > suffer damage (all be it completely predictably, as Elliott found > out). With tank mix you put the oil in as you put in the petrol (if > you remember) and whilst it might not be as accurate it's pretty > obvious that it's going on and where the oil is (and if you crash the > bike your oil might not pour all over the road as easily). ;-) Indeed (analogy not needed), it does show that whatever backup system you choose, no one of them is ideal - you need to consider running at elast two different types of backup. [..] > >> Did you read Elliott's proposed final solution for his backup? > > > >No. > > Ah, worth a read (seriously). Righto, have now. It's not too dissimilar to mine actually. I don't use sparsebundles, but have a mix of data on different drives, I backup the most important data into Time Machine, clone my internal hard drive to an external partition, my Aperture Library is on an external drive, with the Vault on another. Along with another store of my photos in Finder, I have three copies of all my photos (which I'd be most miffed about losing). > >> [3] I wrote him a little batch file that copies said Cardfile > >> data-files to the daily_pen_drive_backup_system I instigated for him a > >> while back. There is a very good chance he doesn't use it, not because > >> he would like to lose his data but because the effort isn't worth the > >> perceived (and proven to be 'nil' over many years so far) risk. > > > >OK, I really don't see the difference here, other than perhaps a > >pen-drive might be considered more volatile as a backup media. > > Because my batch file *just* copies a few fairly specific files from > one directory (well, it uses a bit of a wildcard but only for the file > names), not scans the entire machine for over '400 file types'. Yeah, that's fair enough, but my point was the volatility of the pen drive format. > >> [4] Windows 2000, XP or Vista. Microsoft Internet Explorer 5.5 > >> upwards. > >> > >> http://www.autodata.ltd.uk/technical-specifications.asp > > > >Understandably, most of the motor trade is technologically decades > >behind the rest of the world. > > So being in advance technologically may not be a good thing in this > case. I built the PC for him a few years back out of bits n bobs and > he's happy enough with it. ;-) > > > In many cases garage systems have only > >moved to Windows in the last few years (seriously). > > He's been ahead of the pack then, running Windows 3.1 a good 10 years > ago. ;-) > > > Over the last 30 > >years I've used systems running on, well, firstly a proprietry system, > >then Xenix, and Unix. We only moved to a Windows based system in about > >2003, and indeed there was only one serious Dealer Management System > >that did run on Windows up to then. > > And now it seems many of them do (BMW Diagnostics, the Suntune systems > are two for sure). And the John Deere forward harvesters as I found > out previously. ;-) They do now yes, and IME much less reliable for it. The simplest was Hondas idea of a flashing LED on the ECU. It simply flashed a two digit code, which you cross-referenced with the manual, and found what was wrong in a couple of minutes. More recently I've seen the Windows based units getting to the point of being chucked across the workshop, or attacked by a welding torch (that kind of thing), when you spent an hour trying to communicate with the vehicle. In fact the agricultural stuff has been way ahead of cars for years. -- Andy Hewitt <http://web.me.com/andrewhewitt1/> |