Another thought:  You really want to avoid the LTO4 drives dropping out of 
streaming mode, even if 1Gb/s is enough bandwidth to theoretically move the 
amount of data you need to move.  I believe LTO4 will operate down to 
30-40MB/s.  Worth checking, since I'm not sure, but I'm pretty sure you can 
drop as low as 40MB/s and still stay in streaming mode.  Once you drop out of 
streaming mode, your throughput will go in the dumper, and you won't get 
anything close to 1Gb/s throughput.

At 10:15 AM 2/12/2013, Michael Roesch wrote:
>Hi Stefan,
>
>one quick question: what are the numbers you are using for your
>calculation?
>
>Did you convert 240 MB/s into Gigabit/s?
>
>Thanks
>
>Regards,
>Michael
>
>
>
>On Tue, Feb 12, 2013 at 1:01 PM, Stefan Folkerts
><stefan.folkerts AT gmail DOT com>wrote:
>
>> Yes, two LTO4 drives would not be happy at all behind a 1Gb/s HBA, even two
>> 1Gb/s HBA's are not enough to fully utilize the drives.
>> I would imagine you could also run into driver/firmware issues with this
>> combination since it's a very strange one but then again....it would
>> probably work just slow.
>>
>>
>> On Tue, Feb 12, 2013 at 12:34 PM, Michael Roesch
>> <michael.roesch AT gmail DOT com>wrote:
>>
>> > Hi Stefan,
>> >
>> > the drives are LTO4 ones. So the HBA would be the bottleneck
>> >
>> >
>> > On Tue, Feb 12, 2013 at 11:36 AM, Stefan Folkerts <
>> > stefan.folkerts AT gmail DOT com
>> > > wrote:
>> >
>> > > If it is LTO1 or LTO2 you would be OK, if it is LTO3 or higher you are
>> > > limiting your drivers with your HBA.
>> > >
>> > >
>> > > On Tue, Feb 12, 2013 at 10:39 AM, Michael Roesch
>> > > <michael.roesch AT gmail DOT com>wrote:
>> > >
>> > > > Hi all,
>> > > >
>> > > > we have an old HP MSL 6030 with two drives that share one 1 GBit FC
>> > port.
>> > > > Would that be enough to use with TSM? I have a feeling that says "no"
>> > > but I
>> > > > couldn't find any minimum FC requirements.
>> > > > Anyone having more info? Maybe even an IBM technote?
>> > > >
>> > > > Thanks
>> > > >
>> > > > Regards,
>> > > > Michael Roesch
>> > > >
>> > >
>> >
>>


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