topic Re: Ultrium 4 drives in HP MSL G3 Series Library in Operating System - OpenVMS

Ultrium 4 drives in HP MSL G3 Series Library

The Brit — Thu, 29 May 2008 11:18:14 GMT

We have just installed a new MSL Tape Library and presented it to our test cluster (OpenVMS 7.3-2, and MRU Version 1.8A). No problems with the install, presentation or operation.

My question is: What is the appropriate "/Density=?" value when intitializing LTO3/LTO4 tapes??

Or should I leave off the /Density qualifier and allow the system to use "... a default density of the highest value allowed by the tape drive." (extract from "HELP Init /Density")

Any info, or suggestions appreciated.

Dave

Re: Ultrium 4 drives in HP MSL G3 Series Library

Hoff — Thu, 29 May 2008 16:11:58 GMT

AFAIK, all of the recent generation drives (LTO / Ultrium / SDLT / DDS drives) all sense the particular cartridge, and will select (or prohibit) the appropriate write automatically.

Various of these drives can usually write one or two densities (based on the cartridge loaded), and (usually) some number of additional (lower) densities can be read.

So no /DENSITY on most any recent gear.

If this detail is not in the OpenVMS section of the manual for the drive, send some feedback to HP and ask them to include it. (It's a fairly common question, and it would seem reasonable to address it in the docs.)

Re: Ultrium 4 drives in HP MSL G3 Series Library

The Brit — Fri, 30 May 2008 11:43:14 GMT

Thanks Hoff,
I kinda figured that, I just wanted to hear if anyone had any other ideas.
Just for information, moving our backups from a MSL5026/SDLT library to an MSL/LTO combination reduced our backup times from ~2 hours to ~45 mins.

Dave.

Re: Ultrium 4 drives in HP MSL G3 Series Library

Robert Atkinson — Fri, 30 May 2008 14:04:36 GMT

Might be worth specifying '/MEDIA=COMPACT' though, as not all drives use this by default, and you could reduce the time even further.

Rob.