Re: VIOS on S814 Power8

Kirk Goins <kirkgoins@xxxxxxxxx> wrote on Sat, 21 Jun 2014
15:49:11 GMT:

IBM ( at least in the past ) has recommended Dual VIOS servers
and when talking to support they are amazed if you are not.

This is the best practice.

Think about it, if VIOS goes down, then anything you've
virtualized with that VIOS is down. Essentially, you've wiped
out all the client LPARs too.

So
on Power7 say a 8282-E4D
6 drive Split Backplane $800 ( mirror VIOS drives ) Approx
$800 US List Pair of 5805 SAS Raid Controllers Approx $4,400
US List Total with disks, cables etc.Approx $5,200 US List

I don't understand the need for write cache on adapters nor
disks for anything other than the VIOS LPARs.

If you want internal disk for IBM i, using VIOS to host the
storage is not cost effective considering the performance
overhead. And you would absolutely want the redundancy from
dual VIOS. To get this it means doubling the disk and the
controllers so each VIOS can serve up R0 formatted storage to
each IBM i and you use mirroring in each i LPAR to protect data
on disk.