Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Computing > NZ Computing > Re: 1.5TB drives due in August!

Reply
Thread Tools

Re: 1.5TB drives due in August!

 
 
Lawrence D'Oliveiro
Guest
Posts: n/a
 
      07-14-2008
In message <48785eae$(E-Mail Removed)>, thing wrote:

> get 2 and raid1 it...and dont back up...


Or get 2, put the second one in an older machine, and use it to backup the
first one. That's the most reliable option.
 
Reply With Quote
 
 
 
 
Enkidu
Guest
Posts: n/a
 
      07-15-2008
Lawrence D'Oliveiro wrote:
> In message <48785eae$(E-Mail Removed)>, thing wrote:
>
>> get 2 and raid1 it...and dont back up...

>
> Or get 2, put the second one in an older machine, and use it to backup the
> first one. That's the most reliable option.
>

I like the idea of disk to disk backup in a second machine. But if you
are talking TBytes that a considerable expense. Also you have to have a
reliable method of keeping the two in sync. (I use rsync as I'm sure you
remember). But disk to disk doesn't protect you against lost or damaged
files, does it?

Cheers,

Cliff

--

"I LOVE IT!!" - someone on a newsgroup, somewhere.
 
Reply With Quote
 
 
 
 
JohnO
Guest
Posts: n/a
 
      07-15-2008
On Jul 15, 8:34 pm, Enkidu <(E-Mail Removed)> wrote:
> Lawrence D'Oliveiro wrote:
> > In message <(E-Mail Removed)>, thing wrote:

>
> >> get 2 and raid1 it...and dont back up...

>
> > Or get 2, put the second one in an older machine, and use it to backup the
> > first one. That's the most reliable option.

>
> >

> I like the idea of disk to disk backup in a second machine. But if you
> are talking TBytes that a considerable expense. Also you have to have a
> reliable method of keeping the two in sync. (I use rsync as I'm sure you
> remember). But disk to disk doesn't protect you against lost or damaged
> files, does it?
>
> Cheers,
>
> Cliff


Disk to disk backups don't provide iterations of backups. What if a
file got corrupted a week or month ago and you just realised it now?
Too late if it's a disk backup runs daily.

I'm speaking from a business perspective rather than a home computing
one though. In my world, there is currently no feasible alternative to
tapes. So what if your 1.5Tb database requires 4 LTO3 400Gb tapes in
an automated library to back up? It's a small cost when weighed
against the risk of going out of business due to a loss of enterprise
critical data.
 
Reply With Quote
 
Enkidu
Guest
Posts: n/a
 
      07-15-2008
JohnO wrote:
> On Jul 15, 8:34 pm, Enkidu <(E-Mail Removed)> wrote:
>> Lawrence D'Oliveiro wrote:
>>> In message <(E-Mail Removed)>, thing wrote:
>>>> get 2 and raid1 it...and dont back up...
>>> Or get 2, put the second one in an older machine, and use it to backup the
>>> first one. That's the most reliable option.
>> >

>> I like the idea of disk to disk backup in a second machine. But if you
>> are talking TBytes that a considerable expense. Also you have to have a
>> reliable method of keeping the two in sync. (I use rsync as I'm sure you
>> remember). But disk to disk doesn't protect you against lost or damaged
>> files, does it?

>
> Disk to disk backups don't provide iterations of backups. What if a
> file got corrupted a week or month ago and you just realised it now?
> Too late if it's a disk backup runs daily.
>

Absolutely.
>
> I'm speaking from a business perspective rather than a home computing
> one though. In my world, there is currently no feasible alternative to
> tapes. So what if your 1.5Tb database requires 4 LTO3 400Gb tapes in
> an automated library to back up? It's a small cost when weighed
> against the risk of going out of business due to a loss of enterprise
> critical data.
>

Well, actually a 1.5TB database would likely require 6 or more tapes,
because the quoted 400GB is only a theoretical capacity, but it's the
time that it takes which is the major problem.

Cheers,

Cliff

--

"I LOVE IT!!" - someone on a newsgroup, somewhere.
 
Reply With Quote
 
EMB
Guest
Posts: n/a
 
      07-15-2008
Enkidu wrote:
> Well, actually a 1.5TB database would likely require 6 or more tapes,
> because the quoted 400GB is only a theoretical capacity, but it's the
> time that it takes which is the major problem.



I see a consistent 300GB/hr throughput on a single LTO4 drive on a
mixture of shitty small files. With only larger files things should run
a fair bit quicker. Even at 300GB/drive/hr a decent 3 drive tape robot
would manage a 1.5TB backup in well under a couple of hours.

That's pretty much as quickly as you could copy the data off to a SAN
(which is what we do each night during the available backup window, then
we backup the static copy on the SAN to tape via a single drive during
the day when timeframes aren't an issue).
 
Reply With Quote
 
JohnO
Guest
Posts: n/a
 
      07-15-2008
On Jul 15, 10:12 pm, Enkidu <(E-Mail Removed)> wrote:
> JohnO wrote:
> > On Jul 15, 8:34 pm, Enkidu <(E-Mail Removed)> wrote:
> >> Lawrence D'Oliveiro wrote:
> >>> In message <(E-Mail Removed)>, thing wrote:
> >>>> get 2 and raid1 it...and dont back up...
> >>> Or get 2, put the second one in an older machine, and use it to backup the
> >>> first one. That's the most reliable option.

>
> >> I like the idea of disk to disk backup in a second machine. But if you
> >> are talking TBytes that a considerable expense. Also you have to have a
> >> reliable method of keeping the two in sync. (I use rsync as I'm sure you
> >> remember). But disk to disk doesn't protect you against lost or damaged
> >> files, does it?

>
> > Disk to disk backups don't provide iterations of backups. What if a
> > file got corrupted a week or month ago and you just realised it now?
> > Too late if it's a disk backup runs daily.

>
> Absolutely.
> >> I'm speaking from a business perspective rather than a home computing

> > one though. In my world, there is currently no feasible alternative to
> > tapes. So what if your 1.5Tb database requires 4 LTO3 400Gb tapes in
> > an automated library to back up? It's a small cost when weighed
> > against the risk of going out of business due to a loss of enterprise
> > critical data.

>
> >

> Well, actually a 1.5TB database would likely require 6 or more tapes,
> because the quoted 400GB is only a theoretical capacity, but it's the
> time that it takes which is the major problem.
>


The time is only a problem if it interrupts production. All my clients
run 24/7 with online backups null problemo.

 
Reply With Quote
 
Enkidu
Guest
Posts: n/a
 
      07-15-2008
EMB wrote:
> Enkidu wrote:
>> Well, actually a 1.5TB database would likely require 6 or more tapes,
>> because the quoted 400GB is only a theoretical capacity, but it's the
>> time that it takes which is the major problem.

>
> I see a consistent 300GB/hr throughput on a single LTO4 drive on a
> mixture of shitty small files. With only larger files things should run
> a fair bit quicker. Even at 300GB/drive/hr a decent 3 drive tape robot
> would manage a 1.5TB backup in well under a couple of hours.
>
> That's pretty much as quickly as you could copy the data off to a SAN
> (which is what we do each night during the available backup window, then
> we backup the static copy on the SAN to tape via a single drive during
> the day when timeframes aren't an issue).
>

What brand hardware? If you are willing to say? I'm looking at huge
numbers of tiny files in a deep file system hierarchy. It takes 20 - 40
minutes just to list the files in one of the systems, without actually
reading them.

Cheers,

Cliff

--

"I LOVE IT!!" - someone on a newsgroup, somewhere.
 
Reply With Quote
 
Bruce Sinclair
Guest
Posts: n/a
 
      07-15-2008
In article <487c612c$(E-Mail Removed)>, Enkidu <(E-Mail Removed)> wrote:
>Lawrence D'Oliveiro wrote:
>> In message <48785eae$(E-Mail Removed)>, thing wrote:
>>
>>> get 2 and raid1 it...and dont back up...

>>
>> Or get 2, put the second one in an older machine, and use it to backup the
>> first one. That's the most reliable option.
> >

>I like the idea of disk to disk backup in a second machine. But if you
>are talking TBytes that a considerable expense. Also you have to have a
>reliable method of keeping the two in sync. (I use rsync as I'm sure you
>remember). But disk to disk doesn't protect you against lost or damaged
>files, does it?


A good point. First you need to decide what you are trying to protect
against. Having multiple 'backups' will not save you if they are all in the
same room and the building burns down ... for example. Similarly if the room
is insecure, allowing someone to delete all files and backups.

Different backup methods protect against different risks.

 
Reply With Quote
 
Enkidu
Guest
Posts: n/a
 
      07-16-2008
JohnO wrote:
> On Jul 15, 10:12 pm, Enkidu <(E-Mail Removed)> wrote:
>> JohnO wrote:
>>> On Jul 15, 8:34 pm, Enkidu <(E-Mail Removed)> wrote:
>>>> Lawrence D'Oliveiro wrote:
>>>>> In message <(E-Mail Removed)>, thing wrote:
>>>>>> get 2 and raid1 it...and dont back up...
>>>>> Or get 2, put the second one in an older machine, and use it to backup the
>>>>> first one. That's the most reliable option.
>>>> I like the idea of disk to disk backup in a second machine. But if you
>>>> are talking TBytes that a considerable expense. Also you have to have a
>>>> reliable method of keeping the two in sync. (I use rsync as I'm sure you
>>>> remember). But disk to disk doesn't protect you against lost or damaged
>>>> files, does it?
>>> Disk to disk backups don't provide iterations of backups. What if a
>>> file got corrupted a week or month ago and you just realised it now?
>>> Too late if it's a disk backup runs daily.

>> Absolutely.
>> >> I'm speaking from a business perspective rather than a home computing
>>> one though. In my world, there is currently no feasible alternative to
>>> tapes. So what if your 1.5Tb database requires 4 LTO3 400Gb tapes in
>>> an automated library to back up? It's a small cost when weighed
>>> against the risk of going out of business due to a loss of enterprise
>>> critical data.
>> >

>> Well, actually a 1.5TB database would likely require 6 or more tapes,
>> because the quoted 400GB is only a theoretical capacity, but it's the
>> time that it takes which is the major problem.
>>

>
> The time is only a problem if it interrupts production. All my clients
> run 24/7 with online backups null problemo.
>

How much data? How do you back up?

Cheers,

Cliff

--

"I LOVE IT!!" - someone on a newsgroup, somewhere.
 
Reply With Quote
 
Enkidu
Guest
Posts: n/a
 
      07-16-2008
I LOVE IT! wrote:
> Enkidu wrote:
>> EMB wrote:
>>> Enkidu wrote:
>>>> Well, actually a 1.5TB database would likely require 6 or more
>>>> tapes, because the quoted 400GB is only a theoretical capacity,
>>>> but it's the time that it takes which is the major problem.
>>> I see a consistent 300GB/hr throughput on a single LTO4 drive on
>>> a mixture of shitty small files. With only larger files things
>>> should run a fair bit quicker. Even at 300GB/drive/hr a decent 3
>>> drive tape robot would manage a 1.5TB backup in well under a
>>> couple of hours. That's pretty much as quickly as you could copy
>>> the data off to a SAN (which is what we do each night during the
>>> available backup window, then we backup the static copy on the
>>> SAN to tape via a single drive during the day when timeframes
>>> aren't an issue).
>>>

>> What brand hardware? If you are willing to say? I'm looking at huge
>> numbers of tiny files in a deep file system hierarchy. It takes 20
>> - 40 minutes just to list the files in one of the systems, without
>> actually reading them.

>
> I use Acronis True Image to backup (incremental) my C: drive and data
> drives to an external WD 500GB HD every night after I go to bed.
> Works great. But I can see the day approaching where a bigger backup
> HD will be needed.
>
> Perhaps one of these..
>
> http://www.pp.co.nz/products.php?pp_id=AA07436
>
> http://www.pp.co.nz/products.php?pp_id=AA06034 Raid
>

Thanks John, but I'm talking about much larger arrays spread over many
machines.

Does Acronis do a true backup or is it an image copy (plus
incrementals)? If so, how many backup sets can you keep?

Cheers,

Cliff

--

"I LOVE IT!!" - someone on a newsgroup, somewhere.
 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Re: 1.5TB drives due in August! Enkidu NZ Computing 33 07-18-2008 11:43 PM
Re: 1.5TB drives due in August! Mike Dee NZ Computing 9 07-15-2008 09:23 PM
Re: 1.5TB drives due in August! Enkidu NZ Computing 6 07-13-2008 09:29 PM
How to due with "warning LNK4075: ignoring '/INCREMENTAL' due to Fresh C++ 2 04-22-2008 09:03 PM
Losing Drives - Finding Drives - Losing Drives mel@no.spam.com Computer Support 2 09-21-2007 10:16 PM



Advertisments