HP Surestore Autoloader 818

[Walter W]

Recently, I purchased new Maxell tapes for this device. The new tapes take much longer than the old ones. Does anyone know why this happens?

[Curtis Ballard]

There shouldn't be a problem with Maxell tapes in that drive. It is possible that the new tapes just need to be used a couple of times to break in. The bit error rate on new media is always higher than that of good used media.

I'd try 3 or 4 backups per tape before worrying about it. As long as your backups are completing a higher bit error rate doesn't put your data at risk.

You can run a device acceptance test using HP's Library and Tape Tools utility. It's possible that the drive may just be worn enough that the higher bit error rate of the new media is noticable.

[Walter W]

Thank you for your reply.

I am still concerned about the throughput rate of data onto the new tapes.

Here are the specifics that relate to my problem.

A typical backup starts at 22:00, backs up 114g of data, scan starts @ about 02:00 and scan completes @ 07:00.

With the new tapes, the backup starts at 22:00, one scan started @ 15:00 the next day, one scan started @ 13:30 the next day, another started @13:45 the next day. All of these backups backed-up <110g of data. The first two scans were aborted, the third completed @07:25 for a total of 33 plus hours.

Is the above scenario within noraml tolerance?

What is the URL for HP's Library and Tape Tools utility? What I thought was the link to it(see below) does not work.


http://h20000.www2.hp.com/bizsupport/jsp/ftp:/ftp.hp.com/pub/softlib/software3/COL1977/co-18222-1/hp_ltt34sr1a_win.exe

[Curtis Ballard]

It looks like that page isn't redirecting properly. If you use just the ftp portion of that URL it should work:

ftp://ftp.hp.com/pub/softlib/software3/COL1977/co-18222-1/hp_ltt34sr1a_win.exe

The rate you are getting is a little under 2MB/s which is pretty slow for DLT8000 but within the expected rate if the bit error rate is too high.

If your drive has a lot of tape motion hours it is possible that the head has worn to cornform to the media type you were using previously. Different vendors media has different wear properties even though they are all within the spec. If only one media type is used the head can wear to conform to that media type so that other media types don't work well.

What kind of media were you using before?

[Walter W]

The old media was Maxell. The new media is Maxell. Imation tapes don't even work on this unit.

[Curtis Ballard]

It doesn't sound like media type should be a problem then.

Do the old tapes still have good performance? I'm wondering if it is possible anything else has changed to cause the performance problems.

You can run some performance tests with L&TT using the Dev Perf test to test the drive and the Sys Perf to test your system.

If it is narrowed down to the tapes and you were using Maxell before I don't know of a lot of things to try. There is always the basics
- clean drive a couple of times
- write the tape several times and see if performance improves.

If the problem isn't just that the media needs broke in, I suppose it is possible that you got some bad media. It's rare but does happen that multiple pieces from the same batch can be bad. Check the serial numbers of tapes that are causing problems and see if they are close.