MSL 4048 960 FC Speed Problem

[Mike J Smith]

Hello all,

The MSL tape library I have has two Ultrium drive's installed. The library is connected to a fibre switch. The First Ultrium drive appears to be fine:-

Port A status: Login complete
Speed: 4 Gb/s
Port Type: Fabric (N/F)
N Port ID: 021400

But the second Ultrium drive in the Library is only showing up as being 2 Gb/s?

Port A status: Login Complete
Speed: 2 Gb/s (??)
Port Type: Fabric (N/F)
N Port ID: 021500

Any ideas? Could it be the fibre cable from the Ultrium drive to the fibre switch?

Kind of new to all of this, so any ideas would be much appreciated.

Thanks, Mike

[Curtis Ballard]

The first thing to check is whether the drives are both 4Gb/s drives or if one of them is an older 2Gb/s drive.

There is no performance difference except with highly compressible data so you shouldn't see anything different with a 2Gb -vs- 4Gb link but if the drive is supposed to be 4Gb and is only negotiating to 2Gb then something could be corrected.

The easiest way to tell is to look at the firmware revisions of the drive with the front panel, the web interface, or L&TT. The 2Gb firmware is LxxW and the 4Gb firmware is MxxW.

[Mike J Smith]

Thanks for your reply. I've checked the Firmware version and they are both on 'M22W'.

The first drive backs up fine. The second drive, showing up as 2Gb/s come's up with inconsistency error's in Backup exec as well. Seems to fail over the 150-200Gb mark on 400Gb uncompressed Ultrium tapes.

Is it sounding like a hardware problem?

Many thanks, Mike

[Curtis Ballard · Accepted solution]

This is sounding like there is a hardware problem somewhere in the fibre between the drive and the host.

Is there any way you could just swap the cable between the drives and see if the problem follows the connection?

I'm suspicious that there the speed is due to inability to run at 4Gb and indicative of a problem somewhere.

[Mike J Smith]

Hi Curtis, thanks again for your reply. I've just swapped round the fibre cables going into the back of the Ultriums and amazingly both are now showing up as 4Gb/s??!
Don't really understand that.. but I'll see how the second drive performs in tonight's backup - hopefully no inconsistency errors on either drive!

Many thanks, Mike

[Curtis Ballard]

Fibre is pretty picky about perfectly clean connections. We have had problems in the labs with dust getting in the connectors when we have left the caps off. It doesn't take much to cause the signal to drop way off. Hopefully it was something really simple like that and you're good to go now.

[Mike J Smith]

Just a quick update.. The overnight backups worked fine last night, no inconsistency errors on either Ultrium drive in the library. Checked the second Ultrium drive again this morning and it's still showing as 4Gb/s.

Looks like the problems solved!

Many thanks, Mike