Solved

Snapshots in ESX Server on on the Array?

Posted on 2008-10-03
8
788 Views
Last Modified: 2013-11-14
Hi Guys
I'm looking at virtualising some of our servers but have been scaratching my head over taking snapshots. what is the best way of impklenting these. through Esx server itself or taking the snapshots on the array. The San that i'm looking to purchase is the Dell Equallogics PS5000X and i believe this has software capable of taking snapshots of servers SQL and Exchange.

Any ideas would be welcomed
0
Comment
Question by:staylor1972
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
8 Comments
 
LVL 5

Accepted Solution

by:
HeinoSkov earned 125 total points
ID: 22632559
Hi, snapshots in ESX is only for temporary usage, because it creates a delta file which can grow and grow and grow. This would leave a huge risk on running low on storage if esx snapshots are used in a more common way.

Array-based snapshots would be to prefer, again it depends on what you need to do with the snapshots. If using VMFS then you would need to retrieve the whole LUN from the snapshot to the ESX to get the data back. You could use RDMs to raw device mappings to with array based snapshots to get the features from snapshots you want to use with SQL / Exchange.
0
 
LVL 5

Expert Comment

by:HeinoSkov
ID: 22632563
Just keep in mind that you have a virtualized layer in between that you need to present the snapshot'ted LUNs to.
0
 
LVL 22

Assisted Solution

by:robocat
robocat earned 125 total points
ID: 22632620

ESX snapshots and Array snapshots are complementary.

ESX snapshots can easily rolled back, so these are ideal in case of planned changes. E.g. take a snapshot before you install patches inside a VM if you want to be able to undo these changes quickly. ESX snapshots should not be kept longtime.

Array snapshots are more a protection against logical corruption or accidental deletion of your VMs but it's more difficult to restore from a snapshot.

Remember that snapshots always have some kind of performance penalty (except if you go for a NetApp array).




0
Simple, centralized multimedia control

Watch and learn to see how ATEN provided an easy and effective way for three jointly-owned pubs to control the 60 televisions located across their three venues utilizing the ATEN Control System, Modular Matrix Switch and HDBaseT extenders.

 
LVL 5

Expert Comment

by:valheru_m
ID: 22634272
Be VERY careful using snapshots on exchange and SQL databases (or any other database that maintains state information for that matter).  If you take a snapshot on a machine with a running exchange or SQL database, reverting to that snapshot will only give you a crash-consistent copy of your database.  This is because databases are constantly being written to and often have cached data that has not been flushed to disk. If you need to take a snapshot of any server running these services, make sure that the exchange and/or sql services have been safely stopped before taking the snapshot to avoid potential severe database corruption.
0
 
LVL 5

Expert Comment

by:HeinoSkov
ID: 22636132
That count as Active Directory servers as well :-)
0
 
LVL 56

Expert Comment

by:andyalder
ID: 22641505
Snapshotting won't truncate the Exchange or SQL transction logs either, they'll just grow and grow.
0
 

Author Comment

by:staylor1972
ID: 22648316
Is there any software for ESX server that will allow you to get Exchange or SQL into a safe state before you take a snapshot, without having to stop the virtual server to take the snapshot?
0
 
LVL 22

Expert Comment

by:robocat
ID: 22650196

I'm not aware of any software on ESX level that will do this kind of integration. Of course you can always do your own scripting.

For Storage environments, most big vendors (NetApp, I think also EMC, ...) have software product that tightly integrate with Exchange/SQL to take consistent snapshot backups and also allow e.g. partial restores of databases/single mailboxes from snapshots.

I'm not sure if Equallogics can do this.

0

Featured Post

Building an interactive eFuture classroom

Watch and learn how ATEN provided a total control system solution including seamless switching matrix switch, HDBaseT extenders, PDU, lighting control to build an interactive eFuture classroom.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

A look into Log Analysis and Effective Critical Alerting.
A look at what happened in the Verizon cloud breach.
Teach the user how to install and configure the vCenter Orchestrator virtual appliance Open vSphere Web Client: Deploy vCenter Orchestrator virtual appliance OVA file: Verify vCenter Orchestrator virtual appliance boots successfully: Connect to the …
How to install and configure Citrix XenApp 6.5 - Part 1. In this video tutorial we have explained step by step installation of Citrix XenApp 6.5 Server on Windows Server 2008 R2 is explained in this video. We have explained the difference between…
Suggested Courses

632 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question