unable to increase datastore capacity - can only create new datastore

[emailsling]

Added more storage to the server and I can create a new datastore from it, but I'd prefer to add the storage to an existing datastore. All reside on the same host. The Select Device window is blank:

[daphnissov]

As a general rule of thumb, spanning a VMFS datastore across multiple different devices is a really bad idea and should be avoided as it causes more problems than it resolves.

[emailsling]

thanks for the speedy response daphnissov. May I as then what is the purpose of the option to expand storage?

Is there a better way to grow a RAID10 datastore?

[daphnissov]

The option to expand storage is used for, well, expanding storage. There are multiple ways to expand storage, but the best is to increasing an existing single extent. It sounds like if you're using RAID-10 then it should be a single extent. If you've extended the underlying volume then you *should* see that additional space pop up. If you don't in the HTML5 client, try the Flex client instead.

[emailsling]

We have an existing RAID10 volume and need more storage. Since there is no easy way to grow RAID10 without a full rebuild I created a second RAID10 volume and expected that I'd be able to 'attach' that storage to the existing volume.

I now have two RAID10 volumes; one nearly full and one completely empty. Is there any way to utilize the storage of the second volume to alleviate the congestion of the first?

[daphnissov · Accepted solution]

There should be if that second virtual disk is being presented to ESXi, but now you're increasing your complexity, performance characteristics, and spreading out your failure domain in exchange for more capacity. If you're ok with the risks knowing this, then go ahead. Like I said, though, you should still be able to see this as a new extent but you may need to use the Flex client and not the HTML5 client.

[diegodco31]

The ideal would be to create another datastore.

But check this link: VMware Knowledge Base

Try to expand directly connected to the host.

[emailsling]

I ended up adding it as a separate datastore and migrating resources to it rather than growing the disk.

Thanks for the assistance!

[daphnissov]

I think that's a smart decision on your part.