DLT IV cleaning and poor status

[Thomas Picciani]

We are using a DLT Surestore 6/60 (upgraded from a 4/40) library. The drives are DLT 40/80 I think.

We are using Data Protector (newest version I think)

We have a tape vault containing 350 tapes. The tapes vary in age from new to 5 years old.

We do nightly backups which consume an average of 10 tapes per night.

I have a couple questions because we've had a significant number of tapes become "poor". in the past several months.

1. Does the firmware clean the tapes based on usage?

2. Does the firmware force an unscheduled cleaning if it detects I/O errors or any other problem with the tape?

In the past I've exported and formatted poor tapes because I just felt that we couldn't trust the poor status. I've had fairly new tapes that had perhaps one or two uses go poor. So I felt that the poor condition was in error.

I'd appreciate any advice you guys could give.

Thanks,

Tom Picciani,
Help Desk Technician
Millersville University.

[shah.fuzail]

That's correct Thomas we are facing the same issue since last 2 years.

Recently we have conducted some excercise and reviewd the backup retention and schedule policy, try to utilize the library according to the backup time calculation and verified other factors too.

After all these changes we are not facing this issue on utrium III tapes but ultrium II still showing the same poor mark problem.

Recently HP has recommended us few pacthes which need to upgrade on cell manager and on all the clients systems (unix / wintel) but these patches required reboot of DP server and client as well. Once we conduct this excercise then we'll able to provide you further feedback.

Before that you should review your schedule, retention and frequcy of backup and try to avoid duplication or other minor mistakes.

Thanks,

Shah Fuzail Ahmed

[Marino Meloni_1]

answering your questions:

1- no - the fw do not clean tapes based on usage

2 - depend - the fw may force a unscheduled cleaning if he detect problems reading from tape if autoclean function is set on the library, if not, a cleaning request is sent to the backup application

the poor status usualy indicate some problem with the tape, but as you know, a read/write problem may come from the tape or from the drive, that is why usualy it is better not to use the autoclean function directly on the library, because if you have some defective tapes, each time this tape is loaded, a cleaning cycle will take place. And as the cleaning cartridge are more abrasive than data tape, this unecessary overcleaning will wear the head of the drive, then the "poor" tapes will grow
Better to make the decision to clear the drive yourself when you see that several cleaning request came from a specific drive and from all the cartridges.