Does anyone know the largest supported available space for a vmfs datastore when creating a new vmfs datastore form a 3T lun mapped from a FC storage.

[dandandongdong]

I mapped a 3T lun form FC storage.

And plan to create a vmfs datastore on this lun, when creating, found that the default available space was 1024G, not 3T, so I guess maybe some limitation.

Does anyone know? Many thanks.

[AntonVZhbankov]

Limitiation is 2TB per single LUN. So if you need 3TB VMFS datastore, split it to 2 LUNs 1.5TB each.

---

VMware vExpert '2009

http://blog.vadmin.ru

[Texiwill · Accepted solution]

Hello,

The limit is actually 2TB - 512Bytes

This 512 Bytes is VERY important to not forget.

You only see 1TB as it roles over once you go past 2TBs.

As Anton suggested you can use two 1.5 TB Luns safely. However, you may actually want more 500GB LUNs or such. Going the LARGEST you can is not always the best performing division of resources.

Best regards,

Edward L. Haletky VMware Communities User Moderator, VMware vExpert 2009, Virtualization Practice Analyst[/url]
Now Available: 'VMware vSphere(TM) and Virtual Infrastructure Security: Securing the Virtual Environment'[/url]
Also available 'VMWare ESX Server in the Enterprise'[/url]
[url=http://www.astroarch.com/wiki/index.php/Blog_Roll]SearchVMware Pro[/url]|Blue Gears[/url]|Top Virtualization Security Links[/url]|Virtualization Security Round Table Podcast[/url]

[azn2kew]

I would create 4 x 500GB LUNs for performance reason. If you store too many VMDK on a single LUN, it could create disk I/O issues such as iSCSI Reservation conflicts and eventually lead to thrashing. On average, I would load between 10-15 virtual machines in a LUN. You can use Extents but its not recommended.

If you found this information useful, please consider awarding points for "Correct" or "Helpful". Thanks!!!

Regards,

Stefan Nguyen

VMware vExpert 2009

iGeek Systems Inc.

VMware, Citrix, Microsoft Consultant

[dandandongdong]

Thanks for your reply, the infomation is very important and useful.

[Josh26]

I would create 4 x 500GB LUNs for performance reason. If you store too many VMDK on a single LUN, it could create disk I/O issues such as iSCSI Reservation conflicts and eventually lead to thrashing. On average, I would load between 10-15 virtual machines in a LUN. You can use Extents but its not recommended.

That is of course dependant on how big your VMs are. If you have four VMs 400GB each as we often do, it's entirely appropriate to store them on a maximum sized data store.