Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Rob Findlay

Hi Backup People,

I have set up one of my clients with an Ecrix VXA tape drive using the above
media. It was my understanding that with the hardware compression built into
the drive turned on I would get the full 66 Gig capacity. My client has just
rung me to say that Retrospect is requesting a new tape  a quick inspection
(over the phone via my client) of the original tape in the scheduled backup
set revealed that it has used 33 Gig. I will have to go  investigate this
but could someone who knows please tell me if I need to have software
compression turned on to get 66 Gig out of the tape or is there something
else making Retrospect ask for another tape.

The backup set which was due to be used tonight was set A  Retrospect is
saying that it will call the new tape 2-set A which makes me think it
probably is full.

Thanks in advance to anyone who takes the time to reply
Regards
-- 
Rob Findlay
Mactherapy - Solutions  Support
For Macintosh Computers
http://www.mactherapy.com
*



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How can a client name change?

2001-03-01 Thread David Ross

I use a Mac to backup a Dell PIII to a DAT drive. (This was an
evolution, not a new setup.) Yesterday I realized that the backup wasn't
working because the name of the PC had changed from "Dell PIII
Accounting" to "111ES" about a week ago.

Any ideas as to what could have done this? And the odds of intentional
action by the direct staff are quite low. The machine is on the internet
via an ADSL line through IPNR on a 7100. No ports are mapped to the
Dell. And email isn't used on the Dell. Only surfing.

So are there any reasonable accidental ways this could have happened.
Could it be a virus picked up via surfing?

TIA


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Re: Error -36 (i/o error, bad media?)

2001-03-01 Thread David Ross

The drive where the shap shots are stored is full or corrupt. I had a
similar one a while back and it turned out the drive directory was all
messed up.

 Up until recently, I was running Retrospect 4.3 on a Power Mac 9600, and
 backing up servers and workstations (I work for a book publisher) to a
 Quantum DLT8000 tape drive. A few weeks ago, however, I got a brand new
 G4/466. It's a fairly standard setup (512MB RAM, 30GB IDE HD, Adaptec 2906
 SCSI card, Adaptec 2940UW card, Virex 5.9.1). However, as soon as I ran a
 backup, I began receiving client errors similar to the following
 
 -2/28/2001 11:02:17 PM: Copying Susan McBride on Susan McBride
  Couldn't write Snapshot, error -36 (i/o error, bad media?)
  2/28/2001 11:22:11 PM: 1 execution errors
  Completed: 2479 files, 1.7 GB
  Performance: 85.2 MB/minute
  Duration: 00:19:54 (00:00:13 idle/loading/preparing)
 
 This happens both during normal and recycle backups, but not on all
 machines. Each computer generates a single error during the backup. In
 addition, I receive numerous errors on my G4 (940 of them this morning, as a
 matter of fact), similar to the following
 
 -   Can't read file 3Macintosh HD:Applications (Mac OS 9):Acrobat Reader
 4.0:Resource:CMap:AdobeFnt.lst2, error -36 (i/o error, bad media?).
 
 These files, obviously, aren't getting backed up.
 
 Norton Utilities doesn't show anything amiss on the hard drive, and I've run
 other utilities as well. I have dumped preferences, reinstalled Retrospect
 (along with the ADK v1.8 and Driver Update 2.1), swapped out media, and
 recreated my backup scripts. The computer works great, except for this
 little problem. Looking at the restore options, the snapshots look fine, and
 I can restore files, even from the backups that are generating errors. But
 still, I get this error every morning...and that makes me nervous.


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Re: Macintosh IDE CD-R/RW Support?

2001-03-01 Thread David Rostenne

I tried that as well, but it does not add support for any IDE CD-RW devices...

There's an RDU 2.1 (Retrospect Driver Update) on their site.
It adds support for new CD-RW and tape drives from LaCie, Panasonic,
QPS, Quantum, Seagate, Sony, Yamaha, and others.

For Mac users, the update also allows Retrospect to correctly recognize
the Ecrix VXA AutoPAK and corrects a media spanning issue with certain
TEAC CD-RW drives.

(above is paraphrased from their ReadMe, I think)


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Re: Error -36 (i/o error, bad media?)

2001-03-01 Thread Pam Lefkowitz

On 3/1/2001 7:37 AM, "Brian Caskey" wrote:

 The computer works great, except for this
 little problem. Looking at the restore options, the snapshots look fine, and
 I can restore files, even from the backups that are generating errors. But
 still, I get this error every morning...and that makes me nervous.

Experience tells me that if Retrospect is saying there's a problem, then
there's a problem. You might try running DiskWarrior on the drive. It
frequently fixes things that Norton doesn't (you don't say what version of
Norton you're using or what version of the OS is running, btw). Of course,
just because the computer is new doesn't mean it's perfect. Sometimes even
new stuff doesn't work (don't even get me started here...).

Also check the PowerDomain control panel to be sure the scsi cards are
configured correctly.

It's also possible that your cables inside the computer aren't connected
perfectly. You might want to reseat the ATA cable to the drive.

Just some thoughts,

Pam



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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Garret J. Cleversley

on 3/1/01 6:59 AM, Douglas K Wyman at [EMAIL PROTECTED] wrote:

 I have set up one of my clients with an Ecrix VXA tape drive using the above
 media. It was my understanding that with the hardware compression built into
 the drive turned on I would get the full 66 Gig capacity. My client has just
 rung me to say that Retrospect is requesting a new tape  a quick inspection
 (over the phone via my client) of the original tape in the scheduled backup
 set revealed that it has used 33 Gig. I will have to go  investigate this
 but could someone who knows please tell me if I need to have software
 compression turned on to get 66 Gig out of the tape or is there something
 else making Retrospect ask for another tape.

66gig is the maximum at optimum performance. IE: backing up word files on a
local drive.

I have the latest firmware in my drive and while it helped I still only get
about 34-38 gig per tape.

My setup is a dedicated machine running over a switched 100baseT network
backing up mainly graphics files. I get 180meg/min.

I am very happy with this as graphics files are very compressible (sp?).

Garret

---
Garret J. Cleversley | Vice President | Apple Product Professional
CPI Digital Services, Inc. | Center Page, Inc. | 716-822-2212
• Certified Apple Technician | • Apple Solution Experts, Consultant
A+  Network+ Certified, Member - CompTIA IT Professionals
---



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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Irena Solomon

Retrospect will detect that the drive has compression and will override the
software settings, so having software compression enabled should not affect
performance if you are running Retrospect 4.3 with Ecrix's latest firmware.

Regards,

Irena Solomon
Dantz Technical Support
925.253.3050



 From: Rob Findlay [EMAIL PROTECTED]
 Subject: Re: Ecrix VXA 33/66 tapes with Retrospect
 
 That's what I wanted to know
 Thanks Garret. Thanks also to Douglas who suggested I upgrade the firmware.
 Does anyone use software compression or is this a waste of time? I'm sure it
 slows things down even more.
 -- 
 Rob Findlay
 Mactherapy - Solutions  Support
 For Macintosh Computers
 http://www.mactherapy.com
 *
 
 From: "Garret J. Cleversley" [EMAIL PROTECTED]
 Reply-To: "retro-talk" [EMAIL PROTECTED]
 Date: Thu, 01 Mar 2001 11:04:19 -0500
 To: retrospect [EMAIL PROTECTED]
 Subject: Re: Ecrix VXA 33/66 tapes with Retrospect
 
 on 3/1/01 6:59 AM, Douglas K Wyman at [EMAIL PROTECTED] wrote:
 
 I have set up one of my clients with an Ecrix VXA tape drive using the
 above
 media. It was my understanding that with the hardware compression built
 into
 the drive turned on I would get the full 66 Gig capacity. My client has
 just
 rung me to say that Retrospect is requesting a new tape  a quick
 inspection
 (over the phone via my client) of the original tape in the scheduled backup
 set revealed that it has used 33 Gig. I will have to go  investigate this
 but could someone who knows please tell me if I need to have software
 compression turned on to get 66 Gig out of the tape or is there something
 else making Retrospect ask for another tape.
 
 66gig is the maximum at optimum performance. IE: backing up word files on a
 local drive.
 
 I have the latest firmware in my drive and while it helped I still only get
 about 34-38 gig per tape.
 
 My setup is a dedicated machine running over a switched 100baseT network
 backing up mainly graphics files. I get 180meg/min.
 
 I am very happy with this as graphics files are very compressible (sp?).
 
 Garret



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Re: Backup Problems

2001-03-01 Thread Jeff Grossman

I got a 40G Maxtor Firewire Drive.  I just got it yesterday, so not sure
about the whine yet.  But, it is a room which is not very quick anyway, so I
doubt I would hear it anyway.

I have a Lacie DDS-3 Tape Drive.  I have had it for at least a year now, and
it is working pretty well.  No complaints.

Jeff
-- 
Jeff Grossman ([EMAIL PROTECTED])
Director - Information Systems, Turner's Outdoorsman
http://www.turners.com

 From: [EMAIL PROTECTED]
 Organization: CropCircle Research International
 Date: Thu, 01 Mar 2001 01:57:27 -0500
 To: Jeff Grossman [EMAIL PROTECTED]
 Subject: Re: Backup Problems
 
 jeff -
 
 you're describing my soon-to-be situation to a 'T':  I'll be buying an
 EXTERNAL IEEE 30gig probably tomorrow, using it for backup of my G4/400
 AGP/9.0.4  --  I don't have a tape drive yet, but am plannng on buying
 one in the near future.
 
 questions:
 1) what kind of IEEE drive do you have?  So many brands:  Maxtor,
 Western Digital, EZQuest, IBM.  Is yrs QUIET (ie, it doesn't have a
 high-pitched whine that goes thru yr head and gives you a fever from the
 neck up), and is it reliable?
 
 2) what kind of tape backup system did you decide on?  are you happy
 with it?  is it reliable?  I'm leaning towards an HP DDS-3 or -4 ... IF
 it's compatible with Macs ... I'm not sure about this
 
 3) pls, if anyone writes to you privately, I'd appreciate getting a Fwd
 re: what the fix will be to get the Firewire drive synched-up with yr
 'puter.  (I figure the more info I have going in, the easier my own
 set-up ... I'm out here in the boonies, no helpers around at all ...)
 
 thanks kindly,
 
- ilyes



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Re: Error -36 (i/o error, bad media?)

2001-03-01 Thread Irena Solomon

Hello,

Sometimes the Disk First Aid utility and even Norton can not detect the -36
error. 

Apple's Drive Setup does not do a "low level format" on IDE hard disks,
which means that bad blocks (-36 errors) will not be fixed by using the
format option in Drive Setup. Zero all data is also not helpful.

You should run the "test disk" option in Drive Setup. This will look for and
repair bad blocks (sector sparing as Apple calls it).

Apple's TIL entry for this error:

Type -36 error (I/O Errors) This file is having difficulty while
either reading from the drive or writing to the drive. The file may have
been improperly written data to the drive or the hard drive or disk may be
damaged. This is almost always indicative of a media error (hard error on
the disk). Sometimes (rarely) it is transient.

Solutions: Try copying the file to another drive. Use a disk recovery
software, such as Disk First Aid to examine the disk. You can try rebooting
with all extensions off. Once in a while this will allow you to read the
data. The file in question should be restored from a backup that was stored
on a different disk. Regular backups can reduce the time to recover from
this error.

Regards,

Irena Solomon
Dantz Technical Support
925.253.3050

Try our new Searchable Knowledgebase at:
http://partners.dantz.com:591/faq/


 From: Pam Lefkowitz [EMAIL PROTECTED]
 Subject: Re: Error -36 (i/o error, bad media?)
 
 On 3/1/2001 7:37 AM, "Brian Caskey" wrote:
 
 The computer works great, except for this
 little problem. Looking at the restore options, the snapshots look fine, and
 I can restore files, even from the backups that are generating errors. But
 still, I get this error every morning...and that makes me nervous.
 
 Experience tells me that if Retrospect is saying there's a problem, then
 there's a problem. You might try running DiskWarrior on the drive. It
 frequently fixes things that Norton doesn't (you don't say what version of
 Norton you're using or what version of the OS is running, btw). Of course,
 just because the computer is new doesn't mean it's perfect. Sometimes even
 new stuff doesn't work (don't even get me started here...).
 
 Also check the PowerDomain control panel to be sure the scsi cards are
 configured correctly.
 
 It's also possible that your cables inside the computer aren't connected
 perfectly. You might want to reseat the ATA cable to the drive.
 
 Just some thoughts,
 
 Pam



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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Rob Findlay

That's what I wanted to know
Thanks Garret. Thanks also to Douglas who suggested I upgrade the firmware.
Does anyone use software compression or is this a waste of time? I'm sure it
slows things down even more.
-- 
Rob Findlay
Mactherapy - Solutions  Support
For Macintosh Computers
http://www.mactherapy.com
*

 From: "Garret J. Cleversley" [EMAIL PROTECTED]
 Reply-To: "retro-talk" [EMAIL PROTECTED]
 Date: Thu, 01 Mar 2001 11:04:19 -0500
 To: retrospect [EMAIL PROTECTED]
 Subject: Re: Ecrix VXA 33/66 tapes with Retrospect
 
 on 3/1/01 6:59 AM, Douglas K Wyman at [EMAIL PROTECTED] wrote:
 
 I have set up one of my clients with an Ecrix VXA tape drive using the above
 media. It was my understanding that with the hardware compression built into
 the drive turned on I would get the full 66 Gig capacity. My client has just
 rung me to say that Retrospect is requesting a new tape  a quick inspection
 (over the phone via my client) of the original tape in the scheduled backup
 set revealed that it has used 33 Gig. I will have to go  investigate this
 but could someone who knows please tell me if I need to have software
 compression turned on to get 66 Gig out of the tape or is there something
 else making Retrospect ask for another tape.
 
 66gig is the maximum at optimum performance. IE: backing up word files on a
 local drive.
 
 I have the latest firmware in my drive and while it helped I still only get
 about 34-38 gig per tape.
 
 My setup is a dedicated machine running over a switched 100baseT network
 backing up mainly graphics files. I get 180meg/min.
 
 I am very happy with this as graphics files are very compressible (sp?).
 
 Garret
 
 ---
 Garret J. Cleversley | Vice President | Apple Product Professional
 CPI Digital Services, Inc. | Center Page, Inc. | 716-822-2212
 • Certified Apple Technician | • Apple Solution Experts, Consultant
 A+  Network+ Certified, Member - CompTIA IT Professionals
 ---
 
 
 
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 To subscribe:[EMAIL PROTECTED]
 To unsubscribe:  [EMAIL PROTECTED]
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 Search:  http://www.mail-archive.com/retro-talk%40latchkey.com/
 
 For urgent issues, please contact Dantz technical support directly at
 [EMAIL PROTECTED] or 925.253.3050.
 



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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Garret J. Cleversley

on 3/1/01 11:28 AM, Rob Findlay at [EMAIL PROTECTED] wrote:

 Does anyone use software compression or is this a waste of time? I'm sure it
 slows things down even more.

It slows it down and is unneeded as hardware compression is built in.

Garret

---
Garret J. Cleversley | Vice President | Apple Product Professional
CPI Digital Services, Inc. | Center Page, Inc. | 716-822-2212
• Certified Apple Technician | • Apple Solution Experts, Consultant
A+  Network+ Certified, Member - CompTIA IT Professionals
---



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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Jon Stevens

on 3/1/01 8:04 AM, "Garret J. Cleversley" [EMAIL PROTECTED] wrote:

 I am very happy with this as graphics files are very compressible (sp?).
 
 Garret

Eh? It really depends on the type of file you are compressing.

If the image (or any data for that matter) is already stored in a compressed
format (for example, .gif images are stored compressed), then there is
absolutely no gain and in fact, you might have a negative effect.

For example, a quick and dirty test:

I have a .gif file on disk that is:

12,461 bytes

Compressed with Stuffit, the image becomes:

12,677 bytes

It is actually LARGER in compressed format!

Just wanted to clarify that statement lest anyone become enamored with the
idea that all graphic files compress well.

thanks,

-jon



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RE: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Stephen Jones

You do run the risk of expanding your data if you back it up with
compression... but that depends on the drive technology.

For example, the AIT algo for compression checks to see if the data is
compressible before writing it.  If the data is compressible, it writes a
compressed block.  If the data is not compressible (.gif, .jpg, etc), then
it writes an uncompressed block.  It's able to do that on-the-fly and still
meet the rated transfer speed.

By using this method, you do not run the risk of expanding your data when it
is pre-compressed.  That's why I encourage all of our AIT customers to keep
hardware compression activated.  With other technologies that we distribute,
I advise that they turn compression off when dealing with non-linear video,
audio or pre-compressed graphics, otherwise they will not store the full
capacity.

Steve
www.cybernetics.com
[EMAIL PROTECTED]


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf
Of Daniel O'Donnell
Sent: Thursday, March 01, 2001 2:12 PM
To: retro-talk
Subject: Re: Ecrix VXA 33/66 tapes with Retrospect


I was puzzled by the statement as well. The biggest files these days
tend to be motion graphics or animations such as QuickTime or MPEG.
QT and MPEG are already compressed and will show very little if any
subsequent compression.

At 10:23 AM -0800 on 3/1/01, Jon Stevens wrote:
on 3/1/01 8:04 AM, "Garret J. Cleversley" [EMAIL PROTECTED] wrote:

  I am very happy with this as graphics files are very compressible (sp?).

  Garret

Eh? It really depends on the type of file you are compressing.

If the image (or any data for that matter) is already stored in a
compressed
format (for example, .gif images are stored compressed), then there is
absolutely no gain and in fact, you might have a negative effect.

For example, a quick and dirty test:

I have a .gif file on disk that is:

12,461 bytes

Compressed with Stuffit, the image becomes:

12,677 bytes

It is actually LARGER in compressed format!

Just wanted to clarify that statement lest anyone become enamored with the
idea that all graphic files compress well.

thanks,

-jon



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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Ben Liberman

At 18:48 +0800 3/1/01, Rob Findlay wrote:
Hi Backup People,

I have set up one of my clients with an Ecrix VXA tape drive using the above
media. It was my understanding that with the hardware compression built into
the drive turned on I would get the full 66 Gig capacity. My client has just
rung me to say that Retrospect is requesting a new tape  a quick inspection
(over the phone via my client) of the original tape in the scheduled backup
set revealed that it has used 33 Gig. I will have to go  investigate this
but could someone who knows please tell me if I need to have software
compression turned on to get 66 Gig out of the tape or is there something
else making Retrospect ask for another tape.

For maximum capacity...

1.  make sure VXA drive has the latest firmware
2.  make sure VXA drive has hardware compression turned on
3.  make sure VXA drive favors capacity over speed

There are 2 settings, when configuring the VXA drive, that that 
affect tape capacity...

 capacity [ device] [capacity] [y or n]
 set_compression  [ device] [set_compression] [y or n]

I believe that the factory defaults are:
set_compression  y
capacity n

At 11:42 -0600 3/1/01, Douglas K Wyman wrote:
Streaming tape drives (virtually all modern drives including Exabyte,
DDS-DAT, AIT, VXA, DLT, LTO etc) have a real-time requirement for
data flow. If the backups system is not able to keep the tape drive buffer
above its low water mark, the drive will start writing extended record
gaps (tape with no user data; the lexicon and semantics vary from
vendor to vendor) in order to avoid stopping the tape motion while
waiting for data. Obviously this consumes more tape than if all data
records were written contiguously without record gaps.


Doug,

My understanding is that the VXA drive does packet writes and has a 
variable speed writing mechanism and thus has much less of a problem 
with inter-record gaps (gaps of about 100k per pause with capacity 
turned on with about a 10% loss in speed)

(I'll Bcc: Ecrix tech support on this just in case I have the info wrong.)
-- 
--
  [EMAIL PROTECTED]  Ben Liberman
--


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Re: Ecrix VXA 33/66 tapes with Retrospect

2001-03-01 Thread Douglas K Wyman

At 1:41 PM -0600 3/1/01, Ben Liberman wrote:
1.  make sure VXA drive has the latest firmware
2.  make sure VXA drive has hardware compression turned on
3.  make sure VXA drive favors capacity over speed

There are 2 settings, when configuring the VXA drive, that that affect tape 
capacity...

capacity [ device] [capacity] [y or n]
set_compression  [ device] [set_compression] [y or n]

I believe that the factory defaults are:
   set_compression  y
   capacity n

My understanding is that the VXA drive does packet writes and has a variable speed 
writing mechanism and thus has much less of a problem with inter-record gaps (gaps of 
about 100k per pause with capacity turned on with about a 10% loss in speed)

Ben,
I agree that Ecrix is the company most visibly in touch with this problem.

The principals of the company came from Exabyte and learned from the
experience. The VXA drives do a great deal to compensate for data
starvation, particularly considering the low price point of the product.

Setting the VXA drive parameter to favour capacity, however, will still
increase the number of shoe-shines due to data starvation and therefore
increase the backup time.

You make your choices and take your chances, as they say.

Good comments, taken in context!

Doug.Wyman
Houston TX


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