AIX

Originally posted by: dingdingfish

i have a AIX host, with one HBA, connect to a EMC CX storage via one switch. although only one HBA, from switch to storage, there are two path connect to controller A and controller B.
after cfgmgr, now i can see two hdiskx, i am wondering how to configure MPIO so the two hdiskx will merge into one.
i have googled and search redbooks, no appropriate docs found. thanks a lot.

Originally posted by: SystemAdmin

I think you got confused and iam confused why you are thinking that the 2 disks are 2 different disks. The 2 hdisk...are not 2 different disks, they are 2 paths/psudo disks to a single lun. so you can't merge them. I think what you are looking for is a mpio driver/translator, since each vendor uses their own mpio tool/sw which you install on aix, ask EMC for it, like HP EVA uses Antemeta. Each vendor has their own mpio tool for management. hope this helps. Regards

Originally posted by: dingdingfish

my english is rusty, ;). yes, i know the actually refer the same lun. i just want to know how to use configure the AIX native MPIO.
i have installed EMC powerpath, and it works well. but you know powerpath is not free, so i want to configure AIX MPIO and compare the behavior, but i don't know how to do it.

Originally posted by: SystemAdmin

For many single HBA to CX configurations you can run Powerpath in unlicensed mode at no cost. You get failover but no load balancing. Check with your EMC rep. You also would want the latest ODM usually at ftp://ftp.emc.com/pub/elab/aix/ODM_DEFINITIONS

At least in our environment, AIX 6.1 with 1 HBA connected to a switch with CX storage automatically worked properly with MPIO and failover. If you're running an older version of AIX, you could try upgrading. For 5.3 and older I believe only Powerpath is fully functional.

Originally posted by: jvk

for native MPIO you must ensure that there in no "AIX ODM support for EMC powerpath" disks. That's all.

Remove all EMC disks from aix system, deinstall all EMC filesets (PowerPath & AIX ODM support fileset).
Install "AIX ODM support for MPIO" (provided by free from EMC web page)
After reboot you should get native MPIO disks with EMC ODM definitions what should be fine then.

Originally posted by: SystemAdmin

One should know that to configure storage on an AIX system, one must first have a fileset installed on the system so that the storage is properly recognized and configured. For EMC storage, there are separate filesets depending on if you are using PowerPath or MPIO (you install only one). Once you have the fileset for MPIO installed, then to configure the disk, you run cfgmgr or reboot. If the disk was configured already (not using the supporting fileset), then remove it (rmdev -dl <hdisk#>) and then run cfgmgr. Note that to remove the disk, it cannot be varied on in a VG.

Filesets supporting EMC storage for MPIO are available at ftp://ftp.emc.com/pub/symm3000/aix/ Once installed, you will see that this storage is supported via:

1. lsdev -Pc disk | grep EMC

disk MSYMMRAID1_RDF1 fcp EMC Symmetrix FCP MPIO RDF1 Raid1
disk MSYMMRAID1_RDF2 fcp EMC Symmetrix FCP MPIO RDF2 Raid1
disk MSYMMRAID5_RDF1 fcp EMC Symmetrix FCP MPIO RDF1 Raid5
disk MSYMMRAID5_RDF2 fcp EMC Symmetrix FCP MPIO RDF2 Raid5
disk MSYMMRAID6_RDF1 fcp EMC Symmetrix FCP MPIO RDF1 Raid6
disk MSYMMRAID5_RDF2 fcp EMC Symmetrix FCP MPIO RDF2 Raid6
disk MSYMMRAIDS_RDF1 fcp EMC Symmetrix FCP MPIO RDF1 RaidS
disk MSYMMRAIDS_RDF2 fcp EMC Symmetrix FCP MPIO RDF2 RaidS
disk MSYMM_1RDF1_BCV fcp EMC Symmetrix FCP MPIO RDF1 Raid1 TimeFinder
disk MSYMM_1RDF2_BCV fcp EMC Symmetrix FCP MPIO RDF2 Raid1 TimeFinder
disk MSYMM_5RDF1_BCV fcp EMC Symmetrix FCP MPIO RDF1 Raid5 TimeFinder
disk MSYMM_5RDF2_BCV fcp EMC Symmetrix FCP MPIO RDF2 Raid5 TimeFinder
disk MSYMM_6RDF1_BCV fcp EMC Symmetrix FCP MPIO RDF1 Raid6 TimeFinder
disk MSYMM_6RDF2_BCV fcp EMC Symmetrix FCP MPIO RDF2 Raid5 TimeFinder
disk MSYMM_DISK fcp EMC Symmetrix FCP MPIO Disk
disk MSYMM_DISK_BCV fcp EMC Symmetrix FCP MPIO Disk TimeFinder
disk MSYMM_RAID1 fcp EMC Symmetrix FCP MPIO Raid1
disk MSYMM_RAID1_BCV fcp EMC Symmetrix FCP MPIO Raid1 TimeFinder
disk MSYMM_RAID5 fcp EMC Symmetrix FCP MPIO Raid5
disk MSYMM_RAID5_BCV fcp EMC Symmetrix FCP MPIO Raid5 TimeFinder
disk MSYMM_RAID6 fcp EMC Symmetrix FCP MPIO Raid6
disk MSYMM_RAID6_BCV fcp EMC Symmetrix FCP MPIO RDF2 Raid5 TimeFinder
disk MSYMM_RAIDS fcp EMC Symmetrix FCP MPIO RaidS
disk MSYMM_RDF1 fcp EMC Symmetrix FCP MPIO RDF1
disk MSYMM_RDF1_BCV fcp EMC Symmetrix FCP MPIO RDF1 TimeFinder
disk MSYMM_RDF2 fcp EMC Symmetrix FCP MPIO RDF2
disk MSYMM_RDF2_BCV fcp EMC Symmetrix FCP MPIO RDF2 TimeFinder

Originally posted by: SystemAdmin

Check attached document for MPIO configuration.

Originally posted by: unixgrl

MPIO is on your system by default. You don't have to do anything to configure it.
However, once you install Powerpath, it takes over. So if you want MPIO, uninstall Powerpath.

What you'll see when MPIO is in charge is a single hdisk device. Its not like Powerpath where you have two hdisks which become one hdiskpower device. To see both paths under MPIO you have to use lspath.

$ lspath
Enabled hdisk1 vscsi0
Enabled hdisk1 vscsi1