Unsolved
This post is more than 5 years old
7 Posts
0
620
LUN Strategy
Hi
we're getting an EMC VNX 5500 and I'm relatively new to SAN technology. We're migrating from a HP EVA and I'm taking the opportunity to re-evaluate our LUN setup. Currently we just have a series of 2TB LUNs which are used by various ESX VMs - no specific per-LUN role. I want to know what LUN design strategies you more experienced EMC folk might recommend or use? For instance, do you tend to tier your LUNs according to backup/DR requirements (where a VM is hosted on a LUN where greater replication/RPO/RTO objectives are required)? Perhaps, various "gold service" Production LUNs, several "silver service" Production LUNs, and some LUNs for non-production/testing VMs?
Would be interested to know what strategies are out there.
Thanks
dynamox
1 Rookie
1 Rookie
•
20.4K Posts
0
September 20th, 2013 10:00
in my shop we do not replicate anything on VNX (tier one goes on VMAX) so we just take advantage of FAST and Fast Cache and place everything in one pool and monitor performance to make sure we meet our requirements. For our environment anything less than 20ms response time is good enough.
Madhug1
127 Posts
0
September 20th, 2013 10:00
Hi,
First of all, I would like to say Thank You for choosing EMC VNX.
I would recommend you to take a look at below documents, which would be helpful and clear picure, how you need to proceed.
EMC VNX UNIFIED BEST PRACTICES FOR PERFORMANCE
and
Using VNX Storage with VMWARE vSphere
Thanks
Madhusudan
gingerdazza
7 Posts
0
September 20th, 2013 16:00
Perhaps I wasn't clear..., this question is not performance related. I want to understand what strategies people ploy for LUNs.... Do people assign roles to LUNs (i.e. LUN1 for producyion VMs with tight RPOs) or stick any old VM on them?
zerothehero
64 Posts
0
September 23rd, 2013 01:00
Because every LUN has it's own I/O queue, i'd say it's good to have some kind of mix of High Performing VMs and Low Performing VMs.
If the LUN I/O Queue gets filled by to many high-performers, they will suffer in performance.
On the other hand someone can argue that, if you build a pool with all your disks in there, all I/Os go to the same physical disks and it should make no big difference....but it does
gingerdazza
7 Posts
0
September 24th, 2013 04:00
Isn't the replication at a per-LUN level only? So would it not be relevant to have all VMs together that require the same LUN replication RPO?
So, for instance
LUN1 "HighRPO" (Production Critical services) Replicaiton every 15 minutes
LUN2 "MedRPO" (Production Important Services) Replicaiton every 60 mins
LUN3 "No RPO" (Non Production) Replicaiton every 1 day
??
zerothehero
64 Posts
0
September 25th, 2013 00:00
"Replication" is a different aspect.
If you want to do mirroring between two VNX for Block, you will use MirrorView and this is in general Synchronous. So you will not have to bother with Replication schedules.
But yes, right, if you will be going to mirror your VNX LUNs to another VNX, it is based on LUNs.