Problems with Quantum LTO4 & Retrospect 6.1 on OS X

[warwickt]

Well... I restored everything off of the first BRU tape just fine. The second tape verified OK when making it, and seemed to restore fine, but after two separate restore attempts, half the data is corrupt and it's all data from the RAID volume that went down.

At this point, I think BRU needs a bit more testing to know for sure what's going on. However, I'm of the opinion that the backup is corrupt because the drive had already failed, just not catastrophically at the point of making the backup.

I will do some more testing this weekend.

Hi Jeff, yeah that's a bummer. I would concur with your thoughts on the source being corrupt.

I'm using BRU-PE (beta) at present with the verify option on (autoscan option on by default).BRU-PE is native Intel code for the MACs that use intel not PPC like the BRU-LE.

Data rates from a good disk array to my HP ULTRIUM lTO4 tape drive and my ATTO EXPRESSAS R380 HBA are in excess of 103MB/sec-108MB/sec (uncompressed of course) for archive. I'm using DVCPROHD 1080P 110Mbs footage.

The recall from archive speeds are around 100MB/sec or less depending on the content.. small objects slow the tape drive down.

I am using 2MB (2048KB) buffer size (block size). All these available on the CLI for the old BRU-LE too (-s 4096 etc) .

Yu need something fast as the source else the tape drive will slow down. So you need to sustain at least 100MB/sec from the source else the tape drive will slow down and wait.

This this is an excellent storage device for contemporary media formats such as R3D and DVCPROHD etc.

I recall content from the archive all the time. It works well.

I'd advise most readers to always make two instances ofthe material on two seperate tape volumes.

However this would not have helped in your situation. :waaa:

My workflow is an ARCHIVE workflow more than a backup. I use the HP Ultrium tape drive to archive and restore material onto either of my two raids (MAC interbnal and external pROAVIO).

What i'm looking into is a FCP workflow using SQUAREBOX's CATDV as an SME MAM.

I believe Tolisgroup and SQUAREBOX are working together on something. This would be a terrific workflow if this would be possible.

fwiw

w

[warwickt]

OMFG!!! I had a hard drive crash today! Lost a 1TB HDD in a 3-drive internal RAID-0. Bay #4 in my Mac Pro that has the LTO-4 on it. So BRU is getting put to the test here in just a few minutes. I have a current backup with Retrospect that I did sunday night. But the only backup I have of what I've done over the last 2.5 days is on the tapes I've made today with BRU. A few hours ago, I sat down at this system to start testing the recovery of data through BRU and was greeted by notifications from the RAID utility.

Damn, this is surreal.... After a couple hours, I gave up trying to recover the drive and RAID volume. The drive will spin up, but it grinds, it's toast. I replaced it with another and will be restoring from the BRU tapes shortly. Unfreakingbelievable.

Oh yeah, this is still with the Quantum SAS kit -- LTO-4HH table top drive with LSI 3442E PCI-E SAS HBA. BRU LE 30-day trial edition. The RAID volume is alive again, I'll report back once I have a verdict on restoration.

HI Jeff. reading back through this thread I noted you have elected to use an LSI 3442E PCI-E SAS HBA on your MAC pro with the Quantum HH SAS tape drive.

IS this model Quantum desktop/external HH SAS i/F Ultrium LTO 4 tape drive model TC-L42BN-EY?

1. Does this configuration work ok on OSX at 10.5.5 on your mac pro?
2. what slot did you put it in the mac pro (x4 or x8?)
3. the LSI does tape PASSTHRU then it should work ok with QUANTUM HH SA ULTRIUM 4? IS this true?

FWIW, Tolisgroup support and PAige Jones advised me that LSI HBA did not work with Quantum LTO4 SAS I/Face tape drives on OSX.

I'm still waiting for a microcode/firmware fix from Quantum for there 'out of spec' LTO4 tape drive for one of mine that doesn't work now with ATTOtech EXPRESSAS HBAs on OSX. (see http://attotech.com/support/trouble/sas.html ). Frankly I will NEVER again buy anything from Quantum. They are dreadful for support and trully clueless about media and production (except for STORNEXT) and also quite ignorant OSX.

w
HK

[Jeff Kilgroe]

My Quantum kit is the "LTO-4 HH tape drive tabletop kit SAS HBA bundle, model: TC-L42BN-EZ

It is identical to the TC-L42BN-EY kit except the 'EY kit does not include a SAS cable I think.

It works just fine under OSX 10.5.5
The LSI 3442E is an x8 card, therefore it's installed in an x8 slot.

I had heard that the Quantum + LSI combo was not supported by Tolis Group software. However, I had someone tell me they had just tried it and it seemed to work, so I gave it a shot. Actually, the Quantum LTO-4 HH drive is on their list of supported hardware, but TolisGroup only officially supports Atto and Acard HBA's under OSX. Anyway this drive with the LSI card does seem to work and I will be testing it in greater detail tomorrow.

After losing that 1TB HDD earlier this week, I pulled a 1TB HDD out of a 2-drive CalDigit enclosure and got my array back up so I could restore my data. But I spent all day today re-doing this Mac Pro system. I went ahead and did a clean install of OSX 10.5.5 and cleaned off a lot of crap I don't need. I rebuilt the RAID with 3 new 1.5TB HDDs in a RAID-5 and backed up the new system, I just restored all my data to the new RAID a few minutes ago. I also have an external CalDigit HDPro RAID on this sytem 8x1TB in a RAID-5 and it sustains about 450MB/s. I haven't fully benchmarked the new 3x 1.5TB internall array, but it seems like it's just about as fast and just about as big as the previous 3x1TB, but now with the extra benefits of a RAID-5.

Anyway, I'm going to give BRU another shot tomorrow. Make the same sets of backups and try to restore them to see how it goes.

As for performance, I have found the write speed with Retrospect to be absolutely terrible. It's clear down in the 30MB/s range. Read speed for recall or verify is almost double, but still way lower than what it should be.

With ATempo, there is a few bugs with this hardware combo. ATempo supports the LSI card, but they haven't got around to testing and fine-tuning for the Quantum drive yet. But performance is close to 80MB/s write and 100MB/s reads, but I've had it screw up with drive errors.

In the brief bit I have used BRU LE, I found the speed to be great. I was getting over 100MB/s writes to tape and faster when restoring the data. If the tests work out good, I may contact them about the PE version as it may be a better overall solution and I wouldn't mind testing it out if their beta is still open.

[Jeff Kilgroe]

Having an issue with BRU, but not sure what's causing it or if this is simply the way it works.

BRU is inflating data sizes that are to be written to tape. I didn't notice this last time around as my archive spanned two tapes (about 1.2TB of stuff), it fit without error, so I didn't think much of it. However, when I'm trying to do a new backup now with about 770GB of stuff, BRU is estimating the archive will be nearly 935GB in size. I chalked that up to estimation error last night started the backup and walked away. I return this morning to find BRU sitting there waiting for me to insert another tape after it had already written 800GB to the first tape and it still claimed it had nearly 150GB remaining. ...WTF? Re-checking all the settings, the actual data sizes on the drives, restarting, etc. it still happens. No matter what I attempt to feed it, BRU inflates the on-tape data sizes by about 25%.

Other than this data inflation issue, it works just fine. Files restore fine and to their proper size. It's fast, I'll give it that. Write times are smokin' especially compared to the abysmal performance with Retrospect. I'm getting almost 120MB/s average write to tape, but that is also based on BRU's overinflated numbers. Changing buffer / block sizes don't seem to have an effect on this inflation, nor any other settings I can find to change.

[Dave Blackham]

I don't know that the specific issue is. Tollis support is usually very good but mail or phone. I recall that the buffer size and other presets need to be correctly set for LTO and other devices or errors can occur or performance affected. Check under Bru presets this is from the Tollis site

http://knowledgebase.tolisgroup.com/...try&EntryID=56

TO (All Versions):
Required Hardware Timeout Settings:
The following settings are assigned in the Console Preferences panel and are described on page 78 for the Mac Admin Guide and page 43 for the Linux Admin Guide.
SCSI Timeout: 1032
Online Timeout: 300
Eject Timeout: 1024
Needs Eject Timeout: 300
Additional Suggested Buffer Settings:
The following settings are assigned on the Console Device Configuration panel and are described on page 72 for the Mac Admin Guide and page 44 for the Linux Admin Guide.
Tape Block Size: 256Kb
Write Cache Size: 256MB
Note: Please read TOLIS KB article #15 before making any changes to the tape block size.

Dave

[Dave Blackham]

Hi Jeff, yeah that's a bummer. I would concur with your thoughts on the source being corrupt.

I'm using BRU-PE (beta) at present with the verify option on (autoscan option on by default).BRU-PE is native Intel code for the MACs that use intel not PPC like the BRU-LE.

Data rates from a good disk array to my HP ULTRIUM lTO4 tape drive and my ATTO EXPRESSAS R380 HBA are in excess of 103MB/sec-108MB/sec (uncompressed of course) for archive. I'm using DVCPROHD 1080P 110Mbs footage.

The recall from archive speeds are around 100MB/sec or less depending on the content.. small objects slow the tape drive down.

I am using 2MB (2048KB) buffer size (block size). All these available on the CLI for the old BRU-LE too (-s 4096 etc) .

Yu need something fast as the source else the tape drive will slow down. So you need to sustain at least 100MB/sec from the source else the tape drive will slow down and wait.

This this is an excellent storage device for contemporary media formats such as R3D and DVCPROHD etc.

I recall content from the archive all the time. It works well.

I'd advise most readers to always make two instances ofthe material on two seperate tape volumes.

However this would not have helped in your situation. :waaa:

My workflow is an ARCHIVE workflow more than a backup. I use the HP Ultrium tape drive to archive and restore material onto either of my two raids (MAC interbnal and external pROAVIO).

What i'm looking into is a FCP workflow using SQUAREBOX's CATDV as an SME MAM.

I believe Tolisgroup and SQUAREBOX are working together on something. This would be a terrific workflow if this would be possible.

fwiw

w

Squarebox, DAX and Tollis have an offering and it works better than anything else I know.

Info is on the DAX site if interested.

Dave

[Brian Timmons]

For a Quick Update.

I just got an email from my rep at Tekserve concerning this issue.
He states that the Retrospect techs recommend the LSI 3442e card as the one to use with the Quantum LTO4 SAS drive. Sounds like Jeff Kilgroe may have had a point.

I should be receiving the new card soon.

I'll followup shortly.

Brian

I received my replacement LSI3442E and installed it to see if this
would fix the "hang" issues. Unfortunately the problems persist.

Through my dealer, Tekserve, I am now in touch with an engineer from EMC Insginia to see if they can troubleshoot the problem.

Part of me want's to ditch both this Quantum drive and Retrospect while the other part want's to play ball and see if a solution can be found. The latter is winning so far.

I'm in the process of duplicating the problem with a log file attached that has a record of all scsi bus activity. We'll see if this helps. Meanwhile I have other shoots to deal with and the dilemma of a lot of footage stored on hard drives.

If no solution is found in the next week, I'm demanding an HP LTO and BRU as this is affecting my business.

Brian

[Jeff Kilgroe]

Sorry you're having troubles, Brian...

I'm wondering if you may have a faulty LTO unit and/or cable. Have you tried different cables?

As for me here, I'm dumping Retrospect 6.x. BRU is working fine for me in my latest tests. The over-inflation was caused by a block size mismatch and I didn't understand that I had to re-launch BRU with the proper command line or update profile entries before launching, I was trying to change them from the tapectl interface while BRU was active.

FWIW, I almost bought the HP StorageWorks LTO-4 1760 SAS unit and was deciding between the LSI and ATTO SAS HBAs. But at the time, I couldn't get anyone to confirm that the HP drive worked with their software on OSX and it was $1100 more than the Quantum kit by the time I bought the HP drive and a separate HBA.

Tolisgroup is kinda funny when it comes to OSX... Because of business alliances and politics, they only test and recommend ATTO and Acard HBAs. The Quantum LTO-4 HH drive is supported, but not fully tested. Anyway, it seems to be working just fine once I entered the proper parameters.

[Brian Timmons]

Hey Jeff,

I'm very glad to hear that things are working well with BRU.

I have tried different cables but still have the same problems.
I appreciate the help Retrospect engineers are giving to this problem but I am not a big fan of their software.
While Quantum tried to be helpful, they don't provide much support for Mac users. In fact they essentially wanted me to find a PC to install the drive on to see if it works.
I'm shuttling data around hard drives to buy time.
I wonder if the firmware on the drive might be an issue. Again hard to update since Quantum's tools only allow one to update the firmware on a PC.

I hope to hear from Retrospect engineers shortly.

Brian

[warwickt]

My Quantum kit is the "LTO-4 HH tape drive tabletop kit SAS HBA bundle, model: TC-L42BN-EZ

It is identical to the TC-L42BN-EY kit except the 'EY kit does not include a SAS cable I think.

It works just fine under OSX 10.5.5
The LSI 3442E is an x8 card, therefore it's installed in an x8 slot

.

Hi Jeff, many thanks for the confirmation. I hoping this was the case. I am anxiously awaiting the same LSI HBA from NEXTWAREHOUSE in us&A. Sadly I can't find/source the LSI SAS HBA anywhere here in Hong Kong. The LSI Logic company is a bit useless in the international distributerships like this.

At this stage since firmware changes etc, looks hopeful for the Quantum HH SAS drive with OSx & LSI SAS HBA. This is quite encouraging.

As for performance, I have found the write speed with Retrospect to be absolutely terrible. It's clear down in the 30MB/s range. Read speed for recall or verify is almost double, but still way lower than what it should be.[


In the brief bit I have used BRU LE, I found the speed to be great. I was getting over 100MB/s writes to tape and faster when restoring the data. If the tests work out good, I may contact them about the PE version as it may be a better overall solution and I wouldn't mind testing it out if their beta is still open.

Yes.. especially with an Ultrium 4 tape drive which I'v had up to 113MB/sec uncompressed with BRU-PE for archiving using a 2MB blocksize (buffsize). BRU-PE has a list box with these option up tp 2MB now. I think BRU-LE is only 512KB in list box in the UI.

BRU-PE - I suggest you just contact Tolisgroup and ask. They are really helpful people.

warwick