hp Storageworks DAT 72x6 external speed

[Chris Chan_3]

Use with Adaptec 29160 and Ultra III 68 pin at both ends cable but SCSI BIOS boot up saw speed 40 only not 160??!

Any ideas?? Thanks in advance

Regards
Chris

[Marino Meloni_1 · Accepted solution]

This is his specification, anyway a DDS tape is a serial device and it is very slow compared to HDD access, so you do not need more speed on the bus.

http://h18004.www1.hp.com/products/quickspecs/11985_div/11985_div.html#Technical%20Specifications

[Chris Chan_3]

Hi Marino,

I asked this question because when I used Arcserve with the drive the backup speed can only reach about 150M / minute which I think is too slow.

Chris Chan

[Marino Meloni_1]

Hello Chris Chan,

Usualy the Backup software give just an aproximate value, they do a pure calculation: time start minus time start of the job, reported to the ammount of data. You can understand that you have a in this calculation also the time spent for the prebackup phase, time out due to remote disk calculations, and several other extra time where data are not been transfered.
Also the transfer rate may depend of the data in the server, with highly fragmented data, you can have a slow data transfert.

You can use L&TT to check the transfer rate of your SCSI subsystem (hba > DAT) with the test "Dev Perf"

Marino