I'll add our experiences after a recent p8-vios upgrade FWIW
Previous footprint was an 8202-E4B in a development, HA environment. 8 i lpars, 2 of them each owned 1/2 the disk and hosted disks for the other LPARs.
New is 8286-41A with 2 VIOS lpars using Hitachi SAN disk served to 8 i lpars. All disk is SAN based, none in the CEC, VIOS lives on LUNs on the SAN too. Hitachi does not support NPIV for i. NPIV is used to attach to virtual tape.
Since our two disk environments were so different I can't directly compare IBMi hosted disk vs. VIOS performance, but with dual VIOSes we got multipath access to the disk, I figure that has to be better than not having it.
Since our disk is SAN based, a disk failure is completely transparent to VIOS, all handled internally by Hitachi hardware.
VIOS was a bit of a learning curve for us, but I got help from an AIX guy here, he did a lot of things under oem_setup_env that wasn't in the Redbooks.
It is nice having the redundancy of dual VIOSes, maintenance can be done non-disruptively.
Unless I'm missing something, in order to pass the optical drive around to various lpars, you have to get into SST on the sending lpar as well as the receiver! That's right out of the 80's
Dana
-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Steinmetz, Paul
Sent: Tuesday, January 13, 2015 3:06 PM
To: 'Midrange Systems Technical Discussion'
Subject: IBM i LPAR planning guidlines - traditional, hosted/client, VIOS
There have been many good discussion threads recently regarding VIOS and hosted/client LPARS.
I currently have a combination of 3 traditional and 2 hosted/client LPARS.
The hosted/client LPARs are only for testing i5/OS upgrades, Java, OpenSSH, Open SSL, PTF applies, system restores, etc.
No licenses for 3rd party products on the hosted/client LPARS.
I'm considering VIOS, but have some concerns.
My current disk requirement is 100% SSD for Production LPAR, optimal performance, (1 EXP24S) and 100% 10k spinny for R&D LPAR, optimal capacity (2nd EXP24S) If I go non-VIOS, I'm thinking only 2 LPARS, one for Production, one for R&D. The R&D LPAR would also be a host for the client LPARS.
1) From all the threads, VIOS works better with SAN DASD, not internal/external. I use internal/external.
2) We have large IO demands, I have been told I could see a DASD performance hit with VIOS, is this correct?
3) If using VIOS, and you have a disk failure, from Rob's previous thread, disk management is quite different with VIOS, is this correct?
4) If considering a P7 8205-E6C upgrade to P8 8286-42A, with the EJ0P backplane (18 + 8 ) internal DASD, VIOS may not be a good match.
5) I would like to use the EJ0N with opt EJ0S, P8 split back-plane, 1/2 for each LPAR, but no cache, no controller redundancy, no external SAS ports, not a good option.
6) The P8 CEC includes great features for performance and "hot swap availability), (not true with previous P5, P6, P7 CECS), however, not really suitable for LPARing, at least in my scenario.
I'm sort of "Stymied" at this point, reviewing all the pros/cons of various LPAR methods.
I know what I want to do, just don't sure how I will get there.
Most LPAR docs are dated.
Any new links or docs for LPAR planning.
Thank You
_____
Paul Steinmetz
IBM i Systems Administrator
Pencor Services, Inc.
462 Delaware Ave
Palmerton Pa 18071
610-826-9117 work
610-826-9188 fax
610-349-0913 cell
610-377-6012 home
psteinmetz@xxxxxxxxxx
http://www.pencor.com/
midrange.com
