san luns controller problem

Hi,

I'd like to share this...

I see all the luns on my aix when I do lspv, 10 of them, configured by the san contractor. I defined the first sanvg no problem, the second one no problem, but the third got problem and so on. It's random after the second, I think. The error is 0516-024 mkvg: Unable to open p v.

I did a lot of trial and error, even on another machines. I found out that the luns or vg that cannot be added is the one that is defined on controller b. I asked the san-admin to put it all on controller a. I was able to add it all.

When the san admin is creating the lun on ds4300, it is also random that it will select which controller it needs to use. He mentioned to me that the pathing or zoning is set for controller a for unix-connection.

regards,
itik

Thanks for sharing your problem itik.

AFAIK it is only random in case you don't know what you are doing. :stuck_out_tongue: I am sorry, but your description of the "problem" is so vague, that IMHO it is of little use for others. Could you be more specific? What is the exact hardware setup? Which FC adapter do you use? Which AIX os level? Which multipathing software (RDAC,MPIO,SDD,SDDPCM) with which level do you use? Which SAN switch? Which SAN switch firmwarelevel? Do you use zoning? If yes which type (wwn, port or mixed)? Which DS4K firmwarelevel? You might also want to look into the man pages of lspv and lsdev to find out what information which command returns.

Hi

Ok, when using IBM DS4x series please be sure to run the compatibilty matrix in order to install the correct RDAC fileset levels and well as the latest available firmware for your server's HBAs.

You need to place a call to IBM HW support for that DS4000 Storage System. I recently had a problem with one of my customer's DS4500 systems and it turns to be a problem with the battery that stop access to one controller so LUNs with prefered path to tha controller tried to do failover and errors we logged at AIX level.

Hope this helps

When you have DS4* disk arrays AIX uses the rDAC driver which has the limitation that it can only see one path to the disks per host bus adapter in the machine, that is fsc0 can only be zoned against controler 1 on the disk box and fsc1 against controler 2. If this is not the case, but the fsc0 zoned against both controler 1 and 2, and the same for fsc1 - these situations can ariese. I have selved had such an situation myself which was resolved by rmdev -dl on all the devices, correcting the zoning and cfgmgr again.

I was on vacation...

Thank you for all the advise. But I think it's hard to play with this especially if one of your main application is running on unsupported os aix43.

I will however buy a new san and use the old san that is working right now with one of the aix43 server.

Play safe especially if you are serving 4k client all through out North America.