@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
Nope - I don't think Netbackup is making checksums.
Tape hardware seems to be reasonably adept at detecting big tape errors,
though. This, of course, goes away with disk based backups.
bpverify is just a check of the tape
PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of A Darren
Dunham
Sent: Thursday, October 25, 2007 1:02 PM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
Did I read in this list that netbackup was supposed to do some kind of
checksum on the data
.
-M
-Original Message-
From: Len Boyle [mailto:[EMAIL PROTECTED]
Sent: Monday, October 22, 2007 6:37 PM
To: Donaldson, Mark - Broomfield, CO; veritas-bu@mailman.eng.auburn.edu
Subject: RE: Re: [Veritas-bu] Tapeless backup environments
Hello Mark,
Did I read in this list that netbackup
Did I read in this list that netbackup was supposed to do some kind of
checksum on the data written to tape?
If so would a bpverify check this. I would assume that if netbackup does
this it would find the error.
because netbackup would do it's calc before passing the block to the
dedupe
Why don't we just move on..
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Curtis
Preston
Sent: Friday, October 19, 2007 6:52 PM
To: Eagle, Kent; veritas-bu@mailman.eng.auburn.edu
Cc: [EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup
: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Hall,
Christian N.
Sent: Monday, October 22, 2007 2:55 PM
To: Curtis Preston; Eagle, Kent; veritas-bu@mailman.eng.auburn.edu
Cc: [EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments
Why don't we just move
Here is some required reading on the topic from Val Henson, a noted
academic/storage-guru.
An Analysis of Compare-by-hash
www.nmt.edu/~val/review/hash.pdf
Of particular interst is why hardware error rates can't be compared
with deterministic software errors.
Austin
: Monday, October 22, 2007 10:47 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
Here is some required reading on the topic from Val Henson, a noted
academic/storage-guru.
An Analysis of Compare-by-hash
www.nmt.edu/~val/review/hash.pdf
Of particular
Cc: [EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments
Why don't we just move on..
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Curtis
Preston
Sent: Friday, October 19, 2007 6:52 PM
To: Eagle, Kent; veritas-bu
@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
I don't know. I, for one, am now thoroughly engrossed given Curtis'
honor has been impugned. =P
-Jonathan
From: [EMAIL PROTECTED] on behalf of Hall,
Christian N.
Sent: Mon 10/22/2007 9:55 AM
, October 22, 2007 10:28 AM
To: Austin Murphy; veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
This paper looks to be 5 years old (based on newest references it cites
- it actually cites others that go back nearly 10 years). It would be
interesting to see
I would not think that one would.
len
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED]
Sent: Monday, October 22, 2007 4:52 PM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
I think that part
I wish we had a white board and could sit in front of each other to
finish the discussion, but it's obvious that it's not going to be
resolved here.
You believe I'm missing your point, and I believe you're missing my
point.
what matters is if you use a shorthand to track the
values which can't
Since you've impugned my honor, I feel the need to defend myself a bit,
but I don't want to spend much more time on this topic either:
My first point was that you quoted a Wikipedia article as a source.
The debate as to whether Wikipedia articles have any value is an ongoing
one, and no point in
-Original Message-
From: Jeff Lightner [mailto:[EMAIL PROTECTED]
Sent: Friday, October 19, 2007 12:36 PM
To: Eagle, Kent; Curtis Preston; veritas-bu@mailman.eng.auburn.edu
Cc: [EMAIL PROTECTED]
Subject: RE: [Veritas-bu] Tapeless backup environments
Not an attack - just a question: Did someone
PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments
O.k., at the risk of seeming like I wrote more than you, therefore I
must be right...
2nd. (and last) post on this -
My first point was that you quoted a Wikipedia article as a source.
For me, it really had nothing to do
: [Veritas-bu] Tapeless backup environments?
I wish we had a white board and could sit in front of each other to finish
the discussion, but it's obvious that it's not going to be resolved here.
You believe I'm missing your point, and I believe you're missing my point.
what matters is if you
At the risk of chasing windmills, I will continue to try to have this
discussion, although it appears to me that you're already made up your
mind. I again say that no one is saying that hash collisions can't
happen. We are simply saying that the odds of them happening are
astromically less than
What you must grasp is that it is *impossible* to
represent/re-create/look up the values of 2^65536 bits in fewer than
2^65536 bits--unless you concede that each checksum/hash/fingerprint
will represent many different values of the original data--any more
than
you can represent three bits of
-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Iverson,
Jerald
Sent: Thursday, October 18, 2007 11:52 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
What you must grasp is that it is *impossible* to
represent/re-create/look
] Tapeless backup environments?
What you must grasp is that it is *impossible* to
represent/re-create/look up the values of 2^65536 bits in fewer than
2^65536 bits--unless you concede that each checksum/hash/fingerprint
will represent many different values of the original data--any more
than
---
Message: 1
Date: Thu, 18 Oct 2007 04:06:52 -0400
From: Curtis Preston [EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments?
To: [EMAIL PROTECTED], veritas-bu@mailman.eng.auburn.edu
Message-ID:
[EMAIL PROTECTED]
Content-Type
:[EMAIL PROTECTED] On Behalf Of Eagle,
Kent
Sent: Thursday, October 18, 2007 12:59 PM
To: [EMAIL PROTECTED]; veritas-bu@mailman.eng.auburn.edu
Cc: [EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments
Sorry, but I just can't keep from jumping in at this point.
Not taking either
Glad to have another person in the party. What's your birthday? ;)
Are you seriously suggesting that a quote from Wikipedia constitutes
empirical scientific research?
NO. He said that I was misusing the Birthday Paradox, and I merely
pointed to the Wikipedia article that uses it the same way.
On Thu, Oct 18, 2007 at 01:44:03PM -0400, Curtis Preston wrote:
So you're OK with hash-based de-dupe, which everyone acknowledges has a
chance (although quite small) that you could have a hash-collision and
potentially corrupt a block of data somewhere, sometime, when you least
expect it...
On 10/18/07, Iverson, Jerald [EMAIL PROTECTED] wrote:
...
that is why i have turned off all hardware and software compression on
my tape drives. imagine trying to store more than 400GB of data onto a
single lto3 tape! they say that you can store up to and even more
than 800GB, but i don't
discussion, although it appears to me that you're already made up your
mind.
I'd prefer to say I have little interest in a technology which, by
design, will retrieve a completely different chunk of data than what was
written, with no notice whatsoever. BTW, before you bring out tape
errors
On Tue, Oct 16, 2007 at 12:09:30AM -0400, bob944 wrote:
One of us still doesn't understand this. :-)
Your blog raises a red herring in misunderstanding or misrepresenting
the applicability of Birthday Paradox. The number of possible values in
BP is 366; there is no data reduction in it, no
cpreston [EMAIL PROTECTED]:
As promised, I looked into applying the Birthday Paradox
logic to de-duplication. I blogged about my results here:
http://www.backupcentral.com/content/view/145/47/
Long and short of it: If you've got less than 95 Exabytes of
data, I think you'll be OK.
One
As promised, I looked into applying the Birthday Paradox logic to
de-duplication. I blogged about my results here:
http://www.backupcentral.com/content/view/145/47/
Long and short of it: If you've got less than 95 Exabytes of data, I think
you'll be OK.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf
Of Curtis Preston
Sent: 01 October 2007 06:35
To: [EMAIL PROTECTED]; veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
...
These are odds based on the size
Chris Freemantle said:
It's interesting that the probability of any 2 randomly selected hashs
being the same is quoted, rather than the probability that at least 2
out of a whole group are the same. That's probably because the minutely
small chance becomes rather bigger when you consider many
Bob,
I'll try to respond as best as I can.
No importa. The length of the checksum/hash/fingerprint and the
sophistication of its algorithm only affect how frequently--not
whether--the incorrect answer is generated.
You and I don't disagree on this. The only thing we differ with is the
odds of
On Wed, Sep 26, 2007 at 05:15:08PM -0400, bob944 wrote:
Perhaps anything can have a failure mode where it doesn't alert--but in
a previous lifetime in hardware and some design, I saw only one
undetected data transformation that did not crash or in some way cause
obvious problems (intermittent
cpreston:
Simplistically, it checksums the block and looks in a table of
checksums-of-blocks-that-it-already-stores to see if the identical
ahem, anyone see a hole here? data already lives there.
To what hole do you refer?
The idea that N bits of data can unambiguously be represented by
Just a teensy point - LTO3 tapes should store 400Gb natively. They're
marketed as having a capacity up to 800Gb, but that's with 2:1
compression. We normally get about 550GB for MRI data.
LTO4 are available with 800Gb native capacity. The drives can also
encrypt data.
Dave Markham wrote:
- not the cksum
alone.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of bob944
Sent: Wednesday, September 26, 2007 4:03 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
cpreston:
Simplistically, it checksums
: Wednesday, September 26, 2007 4:03 AM
To: veritas-bu@mailman.eng.auburn.edu
Cc: Curtis Preston
Subject: RE: [Veritas-bu] Tapeless backup environments?
cpreston:
Simplistically, it checksums the block and looks in a table of
checksums-of-blocks-that-it-already-stores to see if the identical
It's interesting that the probability of any 2 randomly selected hashs
being the same is quoted, rather than the probability that at least 2
out of a whole group are the same. That's probably because the minutely
small chance becomes rather bigger when you consider many hashs. This
will still
On Wed, Sep 26, 2007 at 04:02:49AM -0400, bob944 wrote:
Bogus comparison. In this straw man, that 1/100,000,000,000,000 read
error a) probably doesn't affect anything because of the higher-level
RAID array it's in and b) if it does, there's an error, a
we-could-not-read-this-data,
On Wed, Sep 26, 2007 at 09:58:12AM -0400, Jeff Lightner wrote:
I also suggest the argument is flawed because it seems to imply that
only the cksum is stored and no actual the data - it is original
compressed data AND the cksum that result in the restore - not the cksum
alone.
It's not that
On Wed, Sep 26, 2007 at 04:22:01PM +0100, Chris Freemantle wrote:
For our data I would certainly not use de-duping, even if it did work
well on image data.
There are different ways of doing deduplication. Not all of them rely
on hash signature matching to find redundant data. You should talk
Most of this while well documented seems to boil down to the same
alarmist notion that had people trying to ban cell phones in gas
stations. The possibility that something untoward COULD
happen does NOT
mean it WILL happen. To date I don't know of a single gas pump
I can't speak for car
Pls read my other post about the odds of this happening.
With a decent
key space, the odds of a hash collision with a 160=bit key
space are so
small that any statistician would call them zero. 1 in 2^160. Do you
know how big that number is? It's a whole lot bigger than it looks.
And
On Wed, Sep 26, 2007 at 04:02:49AM -0400, bob944 wrote:
Bogus comparison. In this straw man, that
1/100,000,000,000,000 read error a) probably doesn't
affect anything because of the higher-level RAID array
it's in and b) if it does, there's an error, a
we-could-not-read-this-data,
Data Protection, GlassHouse Technologies
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Ed Wilts
Sent: Saturday, September 22, 2007 9:35 AM
To: 'Jeff Lightner'; veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments
]
Sent: Saturday, September 22, 2007 9:47 AM
To: Curtis Preston; 'Justin Piszcz'; 'Jeff Lightner'
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: RE: [Veritas-bu] Tapeless backup environments?
But Curtis, a disk drive by itself isn't very useful either - you'll
need to
a controller or two.
And don't
Ed Wilts said:
1) Disk ages and breaks too.
But with RAID, no longer will the failure of a piece of media cause a
backup or restore failure.
2) Transport is cheap. I'd be surprised if I couldn't transport a
thousand tapes for the cost of a terabyte of storage. Bandwidth to
move data is
connection.
Paul
--
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Ed Wilts
Sent: September 22, 2007 9:35 AM
To: 'Jeff Lightner'; veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup
--
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf
Of Clem Kruger
Sent: September 22, 2007 5:12 AM
To: Jeff Lightner; Justin Piszcz
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Compression on a VTL
Guys i've just read this thread and can say im very interested in it.
The first thing is i learned a new term called deduplication which i
didn't know existed.
Question : I gather Deduplication is using other software. DataDomain i
think i saw mentioned. Where does this fit in with Netbackup and
On Mon, 24 Sep 2007, Dave Markham wrote:
Guys i've just read this thread and can say im very interested in it.
The first thing is i learned a new term called deduplication which i
didn't know existed.
Question : I gather Deduplication is using other software. DataDomain i
think i saw
: Re: [Veritas-bu] Tapeless backup environments?
Guys i've just read this thread and can say im very interested in it.
The first thing is i learned a new term called deduplication which i
didn't know existed.
Question : I gather Deduplication is using other software. DataDomain i
think i saw
.
Atlanta
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Justin
Piszcz
Sent: Saturday, September 22, 2007 10:28 AM
To: Ed Wilts
Cc: veritas-bu@mailman.eng.auburn.edu; 'Jeff Lightner'
Subject: Re: [Veritas-bu] Tapeless backup environments?
Don't even get me
12:43 PM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
On a similar note how does NDMP play with Disk de-dup? All of
the de-dups
I've seem are NAS devices. NDMP only talks to tape or VTL.
Are there VTL's
with De-dup that would solve
Markham
Sent: Monday, September 24, 2007 8:35 AM
To: Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Guys i've just read this thread and can say im very interested in it. The
first thing is i learned a new term called deduplication which i
Time, Saving me Space
and Saving me Money :)
Kind Regards,
Clem Kruger
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Dave
Markham
Sent: 24 September 2007 17:35 PM
To: Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Dave
Markham
Sent: 24 September 2007 17:35 PM
To: Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Guys i've just read this thread and can say im very
PROTECTED]; Jeff Lightner;
veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Do you need a special license for 6.5 or can those with 6.0 licenses
upgrade? I assume you need to open a case with NetBackup to get the
download links?
Justin.
On Mon, 24 Sep 2007
Markham
Sent: Monday, September 24, 2007 11:35 AM
To: Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Guys i've just read this thread and can say im very interested in it.
The first thing is i learned a new term called deduplication which i
Question : I gather Deduplication is using other software.
DataDomain i
think i saw mentioned. Where does this fit in with Netbackup and does
the software reside on every client or just a server somewhere?
In the technologies I'm familiar with--one of them is old, another new,
it's
Simplistically, it checksums the block and looks in a table of
checksums-of-blocks-that-it-already-stores to see if the identical
ahem, anyone see a hole here? data already lives there.
To what hole do you refer? I see one in your simplistic example, but
not in what actually happens (which
On Mon, Sep 24, 2007 at 05:08:31PM -0400, bob944 wrote:
In the technologies I'm familiar with--one of them is old, another new,
it's conceptually simple. The system, whether that's a standalone
system or a box of disk with some smarts or an agent on the backup
client, receives data and
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of A Darren
Dunham
Sent: Monday, September 24, 2007 5:59 PM
To: Veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
On Mon, Sep 24, 2007 at 05:08:31PM -0400, bob944 wrote
PROTECTED] On Behalf Of Clem Kruger
Sent: Monday, September 24, 2007 11:32 AM
To: [EMAIL PROTECTED]; Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Hi Dave,
Yes it is a difficult decision I have looked at DataDomain with
NetBackup. I
Subject: Re: [Veritas-bu] Tapeless backup environments?
I'm not convinced that writing to a DataDomain is going to be faster
than
writing to multiple LTO-3 drives over a SAN. The DD is limited to about
90MB/sec which is on par with 1-2 LTO-3 drives and not much more than
that.
Unless, of course, you
tag.
-Jonathan
From: [EMAIL PROTECTED] on behalf of Ed Wilts
Sent: Sat 9/22/2007 9:35 AM
To: 'Jeff Lightner'; veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Here's some simple math that may help (complements
September 2007 16:34 PM
To: Justin Piszcz
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Disk is not cheaper? You've done a cost analysis?
Not saying you're wrong and I haven't done an analysis but I'd be
surprised if disks didn't actually work out
Wilts, RHCE, BCFP, BCSD
Mounds View, MN, USA
mailto:[EMAIL PROTECTED]
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Jeff
Lightner
Sent: Friday, September 21, 2007 8:44 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: [Veritas-bu] Tapeless backup environments?
Yesterday
To: Justin Piszcz
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Disk is not cheaper? You've done a cost analysis?
Not saying you're wrong and I haven't done an analysis but I'd be
surprised if disks didn't actually work out to be cheaper over
Subject: Re: [Veritas-bu] Tapeless backup environments?
First, you can't compare the cost of disk and tape directly like that.
You have to include the drives and robots. A drive by itself is
useful;
a tape by itself is not.
Setting that aside, if I put that disk in a system that's doing 20:1
To: Justin Piszcz
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Disk is not cheaper? You've done a cost analysis?
Not saying you're wrong and I haven't done an analysis but I'd be
surprised if disks didn't actually work out to be cheaper over
To: Jeff Lightner; veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
We have it on our plan. We will be using tape for only long term retention
of data.
Our plan is to purchase another EMC CDL, and mirror our existing EMC CDL to
the EMC CDL
, 22 September 2007 3:37 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
I think what I'm reading here is that no one has done a true 1-to-1
comparison on Tape versus Deduplication / disk. I guess the next
question is, what would go
Yesterday our director said that he doesn't intend to ever upgrade
existing STK L700 because eventually we'll go tapeless as that is what
the industry is doing. The idea being we'd have our disk backup
devices here (e.g. Data Domain) and transfer to offsite storage to
another disk device so as
On Fri, 21 Sep 2007, Jeff Lightner wrote:
Yesterday our director said that he doesn't intend to ever upgrade
existing STK L700 because eventually we'll go tapeless as that is what
the industry is doing. The idea being we'd have our disk backup
devices here (e.g. Data Domain) and transfer
[Veritas-bu] Tapeless backup environments?
Yesterday our director said that he doesn?t intend to ever upgrade
existing STK L700 because eventually we?ll go tapeless as that is what the
industry is doing. The idea being we?d have our disk backup devices here
(e.g. Data Domain) and transfer
: Friday, September 21, 2007 10:08 AM
To: Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
On Fri, 21 Sep 2007, Jeff Lightner wrote:
Yesterday our director said that he doesn't intend to ever upgrade
existing STK L700 because
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
On Fri, 21 Sep 2007, Jeff Lightner wrote:
Yesterday our director said that he doesn't intend to ever upgrade
existing STK L700 because eventually we'll go tapeless as that is what
the industry
@mailman.eng.auburn.edu;
[EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments?
Discovery Channel
=
Carl Stehman
IT Distributed Services Team
Pepco Holdings, Inc.
202-331-6619
Pager 301-765-2703
[EMAIL PROTECTED]
Jeff Lightner [EMAIL PROTECTED]
Sent by: [EMAIL
Sent: Friday, September 21, 2007 9:44 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: [Veritas-bu] Tapeless backup environments?
Yesterday our director said that he doesn't intend to ever upgrade
existing STK L700 because eventually we'll go tapeless as that is what
the industry is doing
Thanks.
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Friday, September 21, 2007 10:46 AM
To: Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu;
[EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments?
This was in response
-bu@mailman.eng.auburn.edu;
[EMAIL PROTECTED]
Subject: Re: [Veritas-bu] Tapeless backup environments?
Discovery Channel
=
Carl Stehman
IT Distributed Services Team
Pepco Holdings, Inc.
202-331-6619
Pager 301-765-2703
[EMAIL PROTECTED]
Jeff Lightner [EMAIL
]
cc
veritas-bu@mailman.eng.auburn.edu,
[EMAIL PROTECTED]
Subject
Re: [Veritas-bu] Tapeless backup environments?
Cartoon Network.
Did your post have a point? Discovery Channel had a special on this?
You?re annoyed at theoretical questions? wtf?
From: [EMAIL PROTECTED] [mailto:[EMAIL
To
[EMAIL PROTECTED]
cc
veritas-bu@mailman.eng.auburn.edu,
[EMAIL PROTECTED]
Subject
Re: [Veritas-bu] Tapeless backup environments?
Cartoon Network.
Did your post have a point? Discovery Channel had a special on this?
You?re annoyed at theoretical questions? wtf?
From: [EMAIL
@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
We have it on our plan. We will be using tape for only long term
retention of data.
Our plan is to purchase another EMC CDL, and mirror our existing EMC CDL
to the EMC CDL at our DR site. Our master server already is duplicated
@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
I believe disks are 33c/gigabyte and tapes are 3-9cents/gigabyte or even
cheaper, I do not remember the exact figures, but someone I know has
done
a cost analysis and tapes were by far cheaper. Also something that
nobody
Yes, we are in the middle of this (trying to replace D2T2T with D2D2D)
process now.
What I am seeing is that while disk media costs more than tape per TB,
de-duplication is the difference-maker, the enabler, making extra weeks
or months retention of D2D data inexpensive. Buy another appliance
, September 21, 2007 1:10 PM
To: Justin Piszcz; Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
First, you can't compare the cost of disk and tape directly like that.
You have to include the drives and robots. A drive by itself is useful;
a tape
, September 21, 2007 10:38 AM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
Yes, we are in the middle of this (trying to replace D2T2T with D2D2D)
process now.
What I am seeing is that while disk media costs more than tape per TB,
de-duplication
, September 21, 2007 2:06 PM
To: Martin, Jonathan; veritas-bu@mailman.eng.auburn.edu
Subject: RE: [Veritas-bu] Tapeless backup environments?
Oh, I wouldn't say that. ;) We've been doing a lot of comparisons
lately, and the comparisons include all of what you listed plus the cost
differential in cost
-bu@mailman.eng.auburn.edu
Subject: RE: [Veritas-bu] Tapeless backup environments?
I stand corrected. Curtis has all the answers and he's sitting on them.
=P
Worrying about multiplexing settings and tape failures? Come on, that's
about as soft a cost as you can dream up.
-Jonathan
Preston
Sent: Friday, September 21, 2007 1:10 PM
To: Justin Piszcz; Jeff Lightner
Cc: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
First, you can't compare the cost of disk and tape directly like that.
You have to include the drives and robots. A drive
: Curtis Preston [mailto:[EMAIL PROTECTED]
Sent: Friday, September 21, 2007 2:06 PM
To: Martin, Jonathan; veritas-bu@mailman.eng.auburn.edu
Subject: RE: [Veritas-bu] Tapeless backup environments?
Oh, I wouldn't say that. ;) We've been doing a lot of comparisons
lately, and the comparisons
Of Martin,
Jonathan
Sent: Friday, September 21, 2007 12:37 PM
To: veritas-bu@mailman.eng.auburn.edu
Subject: Re: [Veritas-bu] Tapeless backup environments?
I think what I'm reading here is that no one has done a true 1-to-1
comparison on Tape versus Deduplication / disk. I guess the next
On 9/21/07, Jeff Lightner [EMAIL PROTECTED] wrote:
Yesterday our director said that he doesn't intend to ever upgrade existing
STK L700 because eventually we'll go tapeless as that is what the industry
is doing.
snip
Tape has been dying for 30 years.
96 matches
Mail list logo
