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Necessity of Backup DB (log replication) when running 11g under VMware?

Hello - i need to use Oracle standard 11g for a financial software suite. We are on a tight budget since we are starting up, and I was told we need a backup (standby) database to compliment our primary one. So I was quoted approx 30hrs of DBA time to install and build/configure the production database (which is fine), and then an additional 20hrs of DBA time to install 11g and establish standby database for the main production database.. by using log replication... including setting up all necessary scripts, etc. and on top of that I need another $6000 or so for the database log replication stool that provides redundancy in Oracle Std Edition.

Since I'm going to be running the Oracle VM on VMware, I was thinking I would be better off by getting VMware snapshots of the VM (and backup these snapshots using Veeam as well). Wouldnt this be better than going with the secondary (backup) server approach?

I assume restoring from a snapshot would be faster than running off the "standby" DB server - is this correct?

I realize I have to run a script before the snapshot to quiesce the DB prior to export, (pre-freeze/post-thaw script) after the snapshot, but if these are taken care of, would this approach be risky? and then I assume i have to put the control files in the same vmdk file so i can have everything in my snapshot in case something goes wrong.

Also just wanted to note that i am getting an ongoing monthly support package from the same firm that will be doing the initial oracle configuration, and they support vmware even though oracle officially doesn't.

Would 5 support hrs of DBA per month (proactive and reactive) be considered sufficient for a small database with 5 users?

Thank you
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3 Solutions
slightwv (䄆 Netminder) Commented:
>>Since I'm going to be running the Oracle VM on VMware

Are you aware of Oracle's Support position on VMWare?  

In a nutshell:  If you cannot reproduce a problem on a physical machine to 'show' it is Oracle related and not VM related, they will not provide support.

I would not run a production database in VMWare for this reason.

>> Wouldnt this be better than going with the secondary (backup) server approach?

What is being talked about is probably Oracle Data Guard:

It is much more than a backup/recovery tool/platform.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Veeam Backup and Replication, and replicate your Virtual Machine to another location, every 15 minutes.

But the database would be 15 minutes old, so how much data would be lost in that 15 minutes window.

As for restore of the Veeam Backups, you can start virtual machines from Veeam Backup with actually restoring, so Veeam Restores are Very fast! (if not immediate, or at least 5 minutes)
darkbluegrAuthor Commented:
I'm fine with the 15 minute window.. is there any whitepaper from veeam discussing this specifically for Oracle? why is veeam better than a VMware snapshot?

Should I just ask them to go ahead without standby database and without Oracle's log replication software?


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Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
VMware Snapshots are NOT BACKUPS!

A snapshot is NOT a backup of a VM; that is a gross misconception.  

A snap shot is a way to preserve a point in time when the VM was running OK before making changes. A snapshot is NOT a way to get a static copy of a VM before making changes.  When you take a snapshot of a VM what happens is that a delta file gets created and the original VMDK file gets converted to a Read-Only file.  There is an active link between the original VMDK file and the new delta file.  Anything that gets written to the VM actually gets written to the delta file.   The correct way to use a snapshot is when you want to make some change to a VM like adding a new app or a patch; something that might damage the guest OS. After you apply the patch or make the change and it’s stable, you should really go into snapshot manager and delete the snapshot which will commit the changes to the original VM, delete the snap, and make the VMDK file RW. The official stance is that you really shouldn’t have more than one snap at a time and that you should not leave them out there for long periods of time. Adding more snaps and leaving them there a long time degrades the performance of the VM.  If the patch or whatever goes badly or for some reason you need to get back to the original unmodified VM, that’s possible as well.  

I highly recommend reading these 2 articles on VMware Virtual Machine Snapshots:

Understanding Snapshots - http://kb.vmware.com/kb/1015180
Snaphot Best Practices - http://kb.vmware.com/kb/1025279

Also check out the following Snapshot Articles by Eric Siebert

Pt.1- http://is.gd/Lajg4p
Pt.2- http://is.gd/NdKQWC
Pt.3- http://is.gd/tp2vEK
slightwv (䄆 Netminder) Commented:
>>Should I just ask them ...

I cannot advise you on this.  Only you know your uptime/recovery requirements.

>>from veeam discussing this specifically for Oracle

I'm not a VMWare person but there does appear to be some talk on this subject:

I'm not sure if you would need Oracle VSS or not to make this work.

You did catch my comment on being unsupported in VMWare.
darkbluegrAuthor Commented:
thank you both for the insights -

hanccocka - If I may phrase the question now without snapshots, but backups of the VM with either VMware data recovery that came with my essentials plus kit, or Veeam Backup & Replication, would you recommend going this route versus log-based replication of the DB?

slightwv, thank you - understood. Without considering my specific requirements (5 users and small environment overall), in any case - wouldn't VM backup and restore be faster than restoring oracle from the standby server? or would the log-based replication be more robust than what I am suggesting/exploring?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
VMware Data Recovery, will not provided the Step DR functions of Veeam Replication every 15 minutes.
slightwv (䄆 Netminder) Commented:
>>wouldn't VM backup and restore be faster

Cannot speak to that.  I don't know how long a VM backup/restore will take.

You also need to make sure Oracle will be stable during the VM backup.  You cannot just backup live Oracle files.  I don't know veeam but you need to make sure Oracle can be properly backed up with it.  Otherwise you might not be able to restore.

FYI:  Just because you 'test' it once and Oracle recovers does not mean it will every time.  Over the I have played around with different 'backups' of Oracle where the Admins just performed a filesystem backup (including Oracle datafiles).  Some times Oracle can recover.  Other times, not and the database was trashed.

>>restoring oracle from the standby server

You really don't 'restore' from a data guard standby.  You fail over to it.  This gives you the time to rebuild your primary.  You don't have downtime.
darkbluegrAuthor Commented:
Gotcha. I will talk to veeam technical team and see what they say.

This has been very helpful, thank you both very much!

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