Interesting details raised in this discussion (new topic may be warranted).
Can I add a further detail, only applicable I believe to Mac OS 10.8.
I found inadvertently that the hidden partition Recovery HD is not able to
be cloned in this OS by Super Duper. Only the paid version of Carbon Copy
Cloner is able to do that. See the following:
http://macsolvers.wordpress.com/2012/09/20/cloning-a-mountain-lion-installa=
tion/
https://discussions.apple.com/thread/4386330?start=3D0&tstart=3D0
On Thu, Apr 4, 2013 at 11:36 AM, Eric Fassbender <>wr=
ote:
> Kin, I thought I was paranoid about data security but your system is
> outstandingly clever. I am very impressed!
>
> As you suggest, I do the incremental Time Machine backup continuously and
> a fully bootable image using SuperDuper once a month. This way I at least
> have all my tools and entire work setup handy (on the bootable backup)
> should the laptop give up. I can just plug the external hard drive into a
> second Macbook Pro and I am able to work. I can then restore individual
> files from the Time Machine backup as needed while I sort out the problem=
s
> with the broken down laptop. Once the broken laptop is repaired I can use
> the incremental Time Machine backup to restore everything to its former
> glory. That is, if the Time Machine backup disk does not break down in th=
e
> meantime!
>
> However, I only store the finished versions of sound recordings, albums,
> photos and videos on my Macbook. This takes up significantly less space o=
n
> the internal drive and makes the backup much easier/faster while protecti=
ng
> me from running out of internal HDD space too quickly. However, it also
> means that only these final versions get the royal treatment of the doubl=
e
> backup. The raw and intermediate versions are stored on the RAID system
> that I mentioned earlier. I only need them very rarely but still want to
> retain them as I have had some instances where I just needed a particular
> recording that I knew I hadn't used because it was not relevant in the pa=
st
> but had now become the perfect sound effect, for example.
>
> This RAID server is indeed set up as a RAID 5, however, I only do this
> because it features 4 HDD so I can be reasonably sure that there are enou=
gh
> HDD left to re-sync after a failure. Plus, I am not sure that I could jus=
t
> take one of the drives out and plug it into an external case should the
> RAID server itself give up the ghost. With a RAID 1 I can do that since a=
ll
> HDD in the array are an exact clone of the others. So for that reason I
> would use a RAID 1 if I was to use two standard external HDD for a
> (Software) RAID system.
>
> And I might do that soon as my current RAID server solution comes with
> some more restrictions. Apart from the slow connection it takes about 5
> minutes to boot. Plus, in the case of a sudden power outage it needs to
> re-sync the HDD for 2 days! Since in Darwin we have power outages at leas=
t
> once a month and I don't have time to wait for 2 days after each outage f=
or
> my data to sync (while praying that everything works as expected) I have
> given in and purchased a UPS so at least the RAID server is protected fro=
m
> the power outage for up to 30 minutes and I can shut it down properly.
> However, all of this is a bit too cumbersome so for my upgrade of this
> system I really like your solution. I might just compare Retrospect and
> SoftRAID and see what the pro's and con's are. As for HDD's I thought abo=
ut
> Thunderbolt, however, USB 3 provides 5GB/s which is plenty enough for my
> and the extra 5BG/s do not justify the significantly higher costs of thes=
e
> drives for me. All that said, the pain is not big enough yet with my
> current solution so that I would shell out another couple hundred dollars
> for a new solution. I am getting a bit more into videos though lately, so
> this may change the situation very quickly.
>
> Anyway, thanks for sharing your solution, it is very good indeed.
>
> Lastly to answer Peter's "how do you know for sure that it's really
> working as a set? And how will you know when one drive has died?" - The
> RAID server takes care of that. If everything is sweet and dandy it
> displays 4 green lights (one for each HDD) and it says something along th=
e
> lines of "all drives are synchronised". Should there be a problem, I get =
a
> warning. The RAID server even notifies me if a HDD is showing some odditi=
es
> like producing defect sectors. The server then alerts me that this is
> happening and that there is a risk that the HDD might fail in the future =
so
> I can already purchase a replacement before this happens. I've never had =
to
> do this though (knock on wood).
>
> Eric
>
>
> On 03/04/2013, at 11:29 PM, Kin Corning <> wrote:
>
> > Hi Eric,
> >
> > With apologies to others on the list if I'm responding with too much
> detail on this specific topic...
> >
> > Yes, one external drive acts as primary storage for all media files
> (photographs, sound recordings, etc.) and gets backed up to each of 2 oth=
er
> identical external drives. My current drives are 6TB each, which is more
> than enough for all the data I have. To be a bit more detailed, one of
> those backups is a straight clone and the second is an "incremental"
> backup, both maintained using Retrospect (more on this in a moment). The
> advantage of this approach is that the clone is a "warm" copy identical t=
o
> the primary (except for any intervening work since the last backup, which
> as I mentioned is never more than 1 day's work), and thus ready to use
> immediately should the primary drive fail. The clone, however, only has t=
he
> current version of each file on disk. The 2nd "incremental" backup retain=
s
> time history of any changed files, so for example, if a file is
> accidentally deleted or saved in an unintended edited state, or is someho=
w
> corrupted, it is possible to go back and restore an earlier version of th=
e
> file. This "incremental" backup is, however, in a particular format
> specific to the backup software and therefore needs to be restored to a
> clean disk before the data can be used. Having dual backups in this fashi=
on
> gives the best of both worlds. The 3rd offsite backup is also incremental=
,
> and is swapped back and forth with its onsite twin as often as possible.
> >
> > (A small aside is that in this setup it is probably desirable to swap
> the primary drive and the "warm" clone from time to time, so that the
> run-time is evened out between the two drives and the primary is therefor=
e
> less likely to fail. I have done this once over the course of 2 years or
> so.)
> >
> > (Another small aside is that whenever I download new digital photograph=
s
> or sound recordings, I perform the two backups immediately notwithstandin=
g
> my 1-or-2-times-per-day guideline before I do anything else to the files,
> and before I re-format the memory cards from the recorder/camera.)
> >
> > As mentioned I am using Retrospect for both types of backup. At the tim=
e
> I chose it some years ago, it was considered the enterprise-class standar=
d
> for backup up Macintosh computers. Other than reputation, I picked it
> because it did some things I specifically needed which other software did
> not: network backups, backups of mixed Mac and PC machines, and it drives
> my Sony AIT drive which I use to back up selected data to tape. Retrospec=
t
> has gone through several changes in corporate ownership, and I believe is
> now operating as an independent company. There was one period where it
> seemed to be receiving minimal support, though as best I can tell that is
> no longer the case.
> >
> > There are probably simpler solutions if you don't need any of the
> "corporate" type features. If you are on a Mac, Time Machine would do a
> perfectly fine job of the "incremental" backups and any one of a number o=
f
> products (Carbon Copy Cloner for example) could manage the "warm" clone.
> >
> > Incremental backups impose a storage overhead (to keep the earlier
> versions of the file), so if your working practices lead to large files
> changing regularly (for example if regular metadata changes are saved
> within a media file), you may need to think about how this interplays wit=
h
> your backup strategy. The backup software which performs the incremental
> backups will allow you to specify policies about how many past stages are
> retained and at what intervals.
> >
> > There is nothing wrong with using a RAID configuration as the "primary"
> in this strategy -- in fact it would be an improvement over my approach i=
n
> providing some level, albeit imperfect, of intra-day protection. I just
> didn't go down this route again to keep the cost and complexity down. But=
I
> know people who are using Drobos, and others who are using G-Technology
> RAID boxes, and are very happy with them. You just need to recognise they
> are not a complete solution in themselves, and can be costly if they fail=
,
> as per my first note.
> >
> > My units connect to my Mac tower by eSATA, but in today's world USB3 or
> Thunderbolt would be better and more future-proof. As you say, any of the=
se
> will be faster than Ethernet to a network storage box.
> >
> > I am aware that you can construct RAID arrays in the way you suggest
> with software, either with external devices or indeed with internal drive=
s
> within your Mac/PC, but I do not have any direct experience with this
> approach.
> >
> > I'm repeating what you already said to some degree, but there are indee=
d
> different RAID strategies. As you said, RAID Level 1 is a mirror, and is
> often combined with RAID Level 0 ("striping"). RAID 0 often confuses peop=
le
> because it has nothing to do with redundancy -- it simply spreads data
> across 2 or more drives for speed in access. Many of the larger capacity
> drives you can buy today (including the ones I have) in fact have 2 drive=
s
> internally in a RAID 0 configuration for speed, but look like a single
> large drive to the computer, and the RAID provides no backup protection.
> RAID Level 1 (a mirror) is the most secure but least space-efficient of t=
he
> redundant RAID configurations. RAID Level 5 is possibly a better choice f=
or
> redundancy -- in practice is is very secure and is much more space
> efficient than RAID 1.
> >
> > Kin
> >
> > --- In Eric Fassbender <>
> wrote:
> > >
> > > Hi Kin,
> > >
> > > I agree that there is still the element of the RAID server that can
> fail and in your case it has happened, so apparently it is not unlikely. =
So
> I really like your solution/approach. Am I assuming correctly that you us=
e
> one drive that always stays the primary and that then gets backed up to t=
he
> two other external drives? If so, what software are you using to perform
> this feat or do you do it manually? I would be very interested to hear yo=
ur
> feedback as although I am still confident in my RAID, it has the limitati=
on
> that it is slowed down by its only I/O connection - a 1GBit Ethernet
> connection. So I was eyeing a USB3 RAID solution using 2 or 3 standard
> external HDD and SoftRAID 4.5 (Mac), however, I am wondering whether your
> solution offers any benefits over a software RAID?
> > >
> > > For anyone who is not that familiar with RAID systems, there are
> different types of RAID. What we need for data protection/safety is RAID =
1,
> a 'Mirrored Set'. This can be 2 or 3 even 4 drives and they all hold the
> same mirrored data. So always check the specifications because there are
> many RAID solutions out there that offer RAID 0, which makes data transfe=
r
> super fast but does not offer protection against data loss. So if you are
> in the market, look for RAID 1.
> > >
> > > Cheers,
> > >
> > > Eric
> > >
> > >
> > > On 03/04/2013, at 7:49 PM, Kin Corning <> wrote:
> > >
> > > > I would offer some comments about using desktop RAID systems, which
> have been mentioned in this thread.
> > > >
> > > > When RAID arrays are used in Storage Area Networks or other such
> configurations in professional datacenters, *everything* is redundant --
> the servers, the disk storage, power supplies, RAID controllers, and the
> interconnections between server and disk. In a desktop RAID unit, typical=
ly
> it is only the disk drives themselves which are protected. And, while a
> disk is the part most likely to fail, other failures can occur as well.
> > > >
> > > > I was reminded of these limitations the hard way a couple years ago
> when I had a desktop RAID unit fail, apparently (I'll never know for sure=
)
> due to a failed controller board in the box. The device was (just) out of
> warranty, the manufacturer (a major well-known firm) would not offer any
> servicing, and their only suggestion was to buy another identical unit,
> transfer the drives, and see if the data was intact. I did a fair bit of
> exploration and could not find any third-party who had the expertise to
> service the unit, which became an expensive scrap job.
> > > >
> > > > I was backed up separately, so my data was protected, but out of
> curiosity I contacted one of the best known firms in the UK for a quote o=
n
> data restoration, and the answer was =A33000 to give it a try with no
> guarantee of success. This may sound crazy but is understandable given th=
e
> complexity of how data is distributed across drives in the various RAID
> strategies, and the fact that the data may or may not have been corrupted=
.
> > > >
> > > > These desktop RAID units may still be attractive to some in offerin=
g
> a degree of real-time protection against a drive failure, but in my own
> setup (used primarily for photography) I have concluded this benefit isn'=
t
> worth the expense and complexity. I have moved to a simpler system with 4
> identical large-capacity drives, 3 of which are onsite and 1 of which is
> always offsite. Every day (twice a day if I am doing a lot of work) the
> primary drive gets backed up to each of the 2 other onsite drives, and as
> often as is practical one is swapped with the offsite device, to keep the
> data protected from fire or burglary as up-to-date as possible. In this
> setup, I may lose a few hours of work if a drive fails, but on the other
> hand the system is instantly restorable and the cost of replacing the
> failed unit is much lower.
> > > >
> > > > Not to state what may be obvious, but if you choose to use one of
> these units notwithstanding, it is important to remember it is not a back=
up
> device. RAID offers real-time protection against a drive failure, but an
> accidentally-deleted file will be deleted across the RAID array, and any
> software-generated file corruption likewise may be duplicated in each
> 'copy' of the file. So even if you employ one of these units to protect
> your work intra-day, you still need to back up to separate devices
> regularly.
> > > >
> > > > Kin
> > > >
> > > > --- In "sounds.images"
> <sounds.images@> wrote:
> > > > >
> > > > >
> > > > > Many thanks everyone for you words of support and replies, a new
> laptop has been ordered and I do have a caddy already, so will put it in
> ther and have a go at transferring it of it is possible to recover them..
> > > > >
> > > > > Seen in PC world.co.uk is a USB 3.0 1tb external drive for =A359.=
00
> so may grab one..
> > > > >
> > > > > Will update as soon as I can.
> > > > >
> > > > > Simon
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > --- In "sounds.images"
> <sounds.images@> wrote:
> > > > > >
> > > > > > Last night the other half shut down the laptop as normal before
> bed. This morning it was dead. It would power on and fans would spin but
> nothing. Took it to my parents and tried their hard drive in my machine..=
..
> Nothing..
> > > > > >
> > > > > > Tried my hd on their machine and it tried to boot but went
> straight to blue screen of death twice...
> > > > > >
> > > > > > So never put off your back ups. I have lost every recording I
> made since September. It was on the cards to do this little job this
> weekend, but it is too late.. Will try again when I get a replacement
> machine. This was completely unforeseen..
> > > > > >
> > > > > > Oh well... Lesson learned. Never put off the most important job
> of all.
> > > > > >
> > > > > > Simon.
> > > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> > >
> > >
> >
> >
>
>
>
>
>
>
> ------------------------------------
>
> "While a picture is worth a thousand words, a
> sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.
>
> Yahoo! Groups Links
>
>
>
>
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