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Best practice ESX for File Server

SGSIt
SGSIt asked
on
Hello
We want to virtualize our File Server and Database (Sql and Oracle) Servers.
File Server size is about 1 TeraBytes
Oracle and SQL Database size are about 200 GigaBytes.
We use a Dell MD3000i iscsi storage.
So questions is:
What is the best solution to store the data? (i.e. Using standard VMDK , Raw device or other solution)

For example about the File server create a big standard VMDK file (Size 1TB) that contain all users files may be not the best solution; Because in case of corruption of this file we can lose all users data moreover if i need to create a snapshot may be very slow.
Is there a documentation about best pratices about it?
Best Regards
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The best solution would be to use RDMs since you already seem to be using iSCSI SAN to store the physical volumes.
RDMs using Virtual Compatibility Mode allow you to take Snapshots of the Virtual Machines (although in practice, it is not recommended)
You can anyway split your large files in 2Gb files and copy their contents nightly using a batch file or VMware API.

Author

Commented:
Hello
I called "Dell" and "Vmware" and they told me that the better is using standard VMDK.
why?
 
Distinguished Expert 2019

Commented:
For 1TB I'd use RDM rather than VMDK.
nagaraja75 - This would complicate the process. I hope you have not understood the question correctly.
The reason why I suggested RDMs was to make the conversion process hassle-free.
Just create your VMs and point them to the RDMs rather than going through the complex process of P2Ving 1TB of data which IMHO is totally pointless.
 
Top Expert 2010

Commented:
P2V'ing any substantial disk size will make the P2V process take quite a long time. I always recommend to posters to use RDMs (as Arun pointed out) for storage sizes of around 1TB and higher for sure, then for anything slightly less than 1TB...600-900GB...it's really up to them how to attach the storage. But, if the options are to either use RDM or P2V the volume and you want the virtualization process to go quicker and as seamless as possible, I recommend using RDMs. The data is already on your SAN and all you need to do is P2V the system volume (which is typically only around 30GB, unless there is data also stored on it), which takes typically only about an hr to P2V, then connect your SAN storage to your ESX host(s), Edit the new VM's settings by adding a Hard Disk -> RDM, and you're good to go. It's pretty easy...no initializing or formatting of disks...or copying/moving data around, because it's already there.

Hope that helps.

Regards,
~coolsport00

Author

Commented:
Hello
we have not problem of time so we don't want convert the file server but we want to start with a fresh installation of the SAN and after copy the files fron the actual storage to the new MD3000i.
In this case which is the best solution? VMDK or RDM?

Top Expert 2010

Commented:
Well, that's even better...starting fresh! :)

I still recommend using RDM for your TB storage. It keeps your data storage separate from your actual VM. And, it provides flexibility in that, if you do need to move your VM to a different location/server, you can simply move a small VM (i.e. system volume/vmdk), then connect your SAN storage to the new host and your data is there....no re-copying/moving of data is needed.

~coolsport00
I would still stick with RDMs.

Author

Commented:
The VM will be in Vmware cluster.
is there issue to migrate  the VM from an Esx host to another?

Top Expert 2010

Commented:
No...if CPUs are compatible, you can migrate it 'live' (i.e. VMotion). If you need to migrate it to a host outside the cluster, the VM will need to be off.

~coolsport00
Distinguished Expert 2019

Commented:
You won't be able to do live Storage vMotion with RDM but that's not  important, not something you do very often.
Top Expert 2010

Commented:
Actually, in ESX/i4 you can; I did it during my SAN Migration a couple mos back. :)

~coolsport00
coolsport00, just to be cent percent right on this, only VMs with Virtual Compatibility Mode in RDM can be VMotioned. I hope I am correct about this.
Top Expert 2010

Commented:
I think that was the 'before' stipulation...but either mode works (I had both). I had an Engineer here during that time that assumed the same thing (as did I), but we were able to sVmotion regardless. Good stuff!
coolsport00 - Can you confirm this ?

I was under the impression that VMotion is not possible under Physical Compatibility Mode in RDMs since the VMDK only has a index information about the RDM and all connections get initiated between the Guest OS and the RDM Drive.
Top Expert 2010
Commented:
I can confirm because I actually did it :) Both me and the engineer assisting with our SAN migration were pleasantly surprised. I hadn't researched anything on it. I was under the impression that only Virtual Compat Mode was sVmotion-able as well. It wasn't the case when I migrated to my new SAN. We actually did a test to confirm it.

~coolsport00