Reserved LUN Pool Relocation

Thanks for the quick reply, yes, they are in use for MV/A

those are private LUNs so i don't' think you can migrate them using Lun migration utility. Are they actually in use ? What are they used for snapview or sancopy ?

Sounds like a plan, thanks...
When you say "shut down MV for a minute or so..." I should use AdminFracture for this step, correct?

If I AdminFracture the MV/A luns, I shouldn¿t have to perform the full synch for those luns once the replication restarts, correct?

If the LUN's you're replicating have WIL's attached the re-sync will be incremental, indeed (WIL = Write Intend Log).

You don't need the LUN migration utility. If they're not in use, you can pull them out of the RLP at any time, just make sure you replace them with new ones asap just incase the Clariion needs them.

If possible yes. Most customers know have the maximum amount of LUN in the RLP, so adding just 1 isn't even possible before you take 1 out first. But you're right !

To be safe I would just add the new FC RLP LUNs in first. That way when you remove the STATA LUNs from the pool you are not at risk of not having enough RLP storage available.

Really? They either have old arrays or are really using a lot of RLP storage since the newer arrays support hundreds of LUNs in the pool.

Reserve LUNs (RLP) are used by Mirrorview/A - one for the source LUNs - a RLP gets assigned as soon as you add the secondary image, and one of the mirror when the sync is running. When sync is complete, the RLP is released from the secondary image.

For snapshots - you will need to stop the session for each snap to release the RLP.

Incremental SNA Copy - the RLP is used to track all changes on the source LUN - will need to destroy the SAN Copy session to release the RLP.

Remember that if you are using snapshots that there is a minimum size for RLP based on the largest source LUN - I believe it's 2% - so if you snap a 2TB LUN, you will need to have a 200GB RLP - but you can not manually assign RLP from the pool. when a snap session starts it will take the next available RLP.

Reserve LUNs

White Paper: EMC CLARiiON Reserved LUN Pool Configuration Considerations - Best Practices Planning

http://powerlink.emc.com/km/live1/en_US/Offering_Technical/White_Paper/H1585_clariion_resvd_lun_wp_ldf.pdf


glen

CX300 and CX3-10 and CX3-20 at most customers at the moment. Only now, since about a year are the new CX4's being installed. I remember that only 25 LUN's can be placed in the RLP on CX300 and about 50 in CX3's.... The newer CX4 can hold much more, I know.
Unfortunately most custmoers don't have fancy CX4-480's and higher The 120 and 240 are very popular....

That's why I said that you need to do it one by one and not all at the same time.



Uhm.... 2% of 2TB is 20GB, not 200....

You sure on those RLP LUN numbers for the Cx3? I thought it was 128 for the Cx3-20, 256 for the Cx3-40, and 512 for the Cx3-80. And the Cx line was 25/50/100 for the Cx3/5/700.

I did a little more digging after my post and found that when the Cx3 line was initially released, running FLARE release 22, they supported 50/100/100 RLP LUNs for the Cx3-20/40/80 respectively.

So Rob has some customers still running old FLARE on their Cx3s

yeah, i know i put at least 80 when i was SanCopy'ing from CX600 to DMX4.