Configuring a two-RAID LUN

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Clariion 300
Dell
EMC CLARiiON
LUNs
RAID
RAID 1
I need to expand a couple of LUNs and am seeking advice regarding how to proceed. We are using a Dell/EMC Clarion 300. We have two RAID groups (1 and 2) that had multiple LUNs on each RAID group with the LUNs assigned to different servers (I know, bad idea). Only one server uses the two RAID groups now and I'd like to allocate all space in each RAID group a single LUN in each RAID group (i.e., Expand LUN 12 to use all disk space in RAID Group 1 and expand LUN 21 to use all disk space in RAID Group 2).
RAID Group 1: 
Server F is using 60 GB (LUN 12) on RAID Group 1 (configured as RAID 1). 73 GB on RAID Group 1 is free and unallocated (no LUN created). I want to allocate this unused 73 GB on RAID Group 1 to Server F (i.e., expand LUN 12 to use the additional 73 GB). 
RAID Group 2: 
Server F is using 250 GB (LUN 21) on RAID Group 2 (configured as RAID 5). Server B was using 250 GB (LUN 22) on RAID Group 2. 300 GB on RAID Group 2 is free and unallocated. I want to allocate the 250 GB (LUN 22 assigned to Server B) to Server F and allocate the 300 GB unallocated space to Server F (i.e., expand LUN 21 to use all the space on RAID Group 2). 
None of the LUNs are part of a snapshot, clone, mirror or SAN Copy session. 
Regarding RAID Group 1: 
Do I need to create a LUN from the unallocated 73 GB on RAID Group 1, then expand LUN 12 using the Expand Storage Wizard? 
If so, when I expand the LUN do you recommend I choose Stripe or Concatenate Expansion? 
Regarding RAID Group 2: 
Do I need to destroy LUN 22, then create a LUN using the unallocated space, then expand LUN 21 using the Expand Storage Wizard? If so, when I expand the LUN do you recommend I choose Stripe or Concatenate Expansion? 
ASKED: January 25, 2010  4:25 PM
UPDATED: January 25, 2010  7:41 PM

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The easiest way to do this would be to remove all the un-used LUNs from the array. Then create one new LUN in each RAID Group that takes the available free space.

Then you’ll want to stripe from the existing LUN to the new LUN that it shares the RAID Group with so that you have one meta lun which takes up the entire RAID Group.

FYI, there is nothing wrong with having multiple servers using LUNs in a single RAID Group. SAN Storage Arrays are designed to handle that without issue so long as the total IO isn’t more than the RAID Group can handle.

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