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Re: Backup / Restores slower using FC connected LT04 verses SCSI connected LT04

 
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Maddog1
Advisor

Re: Backup / Restores slower using FC connected LT04 verses SCSI connected LT04

The server is connected by fibre to a 9503 switch04. It is zoned to a Storagetek SL8500 tape library on a Cisco 9216. Did I mention the server is in Kentucky and the tape drive in Ohio? 

Hoff
Honored Contributor

Re: Backup / Restores slower using FC connected LT04 verses SCSI connected LT04

That data link is an excellent candidate for the bottleneck here.  

 

And no; you hadn't mentioned that detail.  

 

How big is that pipe?  

 

Does that capacity match (approximately) what you're seeing as your performance limit?

 

For DT, you may want to look at shadowing or some other mechanism which (when operating normally) avoids having to load the full contents of the disks over a limited link.  

 

Host-based volume shadowing (HBVS) can (with mini-merge and mini-copy) can try to avoid that, by transferring only the "delta".  

 

Some databases can also maintain these "deltas" from the last full archive, too.  

 

And there's the RMS Journaling mechanisms that can potentially be useful for these cases.

Maddog1
Advisor

Re: Backup / Restores slower using FC connected LT04 verses SCSI connected LT04

It looks like upping the blocks to 61440 has done the trick. 15 - 28Mb/Sec oppose to 2Mb/Sec

I will amend the live backups to make sure they use this block count in future.

 

Thanks for everyones contributions.