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80 Posts
0
2804
June 3rd, 2014 08:00
Vmax - Expanding MetaLun 3 TB to a 7 TB
Hi All ,
I'm new to vmax and still learning , need your expertise please , we have a request to expand a metalun . My plan is as below , let me know if Im doing it right , I cant seem to find any docs reg best practises for metaluns on vmax .
Vmax 20 K - 5876 . SE -- 7.2.1.0
Concatenated :
Metalun currently at ---- 3TB= 16 TDEVS X 192000 MB
To be expand by creating -- 4TBI ~ 22TDEVS X 192000 MB ..
Im planning to create 22 TDEVS of 192000 MB each and add these to the metahead . . Is this approach good?
What other ways can I expand this other than migration .
All meta members should be at the same size for concatenatenation ?
What points to I have to keep in mind before i perform any meta expansion (other than size ) .
Peace !
Quincy561
1.3K Posts
1
June 3rd, 2014 09:00
The members do not need to be the same size for a concatenated meta, AFAIK, but it is probably not a bad thing to keep them the same size.
Not sure what the performance requirements for this 7TB volume is, as a striped meta may offer more performance. You can add FAs instead of striping and get more performance as well.
asceticenergy
80 Posts
0
June 3rd, 2014 10:00
Performance is not a problem . The concats should do just fine for the app its serving .
So overall mixing sizes for a concat meta is not a problem . Good to know this .
Yes I should get SE up soon , thanks for pointing this out .
Also any white paps /docs for meta luns alone - vmax ?
Peace!
asceticenergy
80 Posts
0
June 3rd, 2014 10:00
Cheers Quincy
M_Salem
213 Posts
1
June 3rd, 2014 10:00
For concatenated META LUNs, The members do not have to be of same size.
Meta Configuration : Concatenated
Meta Device Members (2) :
{
----------------------------------------------------------------------
BCV DATA RDF DATA
---------------------------- --------------------------
Sym Cap Std Inv BCV Inv Pair R1 Inv R2 Inv Pair
Dev (MB) Tracks Tracks State Tracks Tracks State
----------------------------------------------------------------------
--> 0C17 5250 - - N/A - - N/A
0059 1031 - - N/A - - N/A
----------------------------------------------------------------------
6281 - - - -
}
Quicny56, has a very good point which is considering converting the META device to Striped for a better performance. You can then expand the device on the fly but this will need you to create a fully preallocated thin BCV device of same size and configuration as the current 3 TB device. You will first convert the device to Striped with preserve_data_option set to yes and then expanding it with preserve_data_option set to yes.
Consider upgrading SE v7.2 as it went EOSL and the minimum we recommend with 5876 is SE v7.4
Hope that helps
Mohammed Salem
asceticenergy
80 Posts
0
June 3rd, 2014 12:00
Im creating 22 Tdevs of 192000 MB each to make it ~ 4 TB ..
the number 22 sounds odd as its not a power of 2 .. but as this is VP Im ignoring the base 2 thing .... Hope im doing it right .
AranH1
2.2K Posts
0
June 3rd, 2014 13:00
I don't think you should just consider upgrading SE to 7.6, I would consider it mandatory. SE 7.4 was the first version to offially support Enginuity 5876.
Since you are using virtual pools the meta count doesn't matter. Quincy56 likes powers of two though (or at least even numbers) so if you want to make him happy you should use even numbers ;-)
Quincy561
1.3K Posts
0
June 3rd, 2014 13:00
With VP, it really doesn't matter if it is even or powers of 2. That matters when the volumes are traditionally provisioned (thick)
asceticenergy
80 Posts
0
June 4th, 2014 06:00
Agreed ..
Cheers Quincy :-)
asceticenergy
80 Posts
0
June 4th, 2014 06:00
Thanks Aran , point noted .
Lol I know Quincy's love for the power of 2
.
snalluri
28 Posts
1
June 6th, 2014 08:00
As per best practices, powers of 2 works good if the device is thick.
asceticenergy Concatenated metalun can be expanded from 3 TB to 7 TB on fly but will have some performance issues. Not sure if we can expand a striped meta device on fly !!
AranH1
2.2K Posts
1
June 6th, 2014 09:00
Snalluri,
The ability to expand a striped metavolume online has been available for some time now. The solutions enabler array controls product guide has the details.