topic Re: Windows Server 2008 R2 sees lun twice... Host utils are installed! in Data Protection

Windows Server 2008 R2 sees lun twice... Host utils are installed!

oweinmann — Thu, 05 Jun 2025 07:02:54 GMT

Hi,

We have a very strange problem here.

Server 2008 R2 1 Qlogic HBA FC hostutils 5.3 installed. Connected luns are shown twice. I remeber that this was a problem if hostutils are not installed. But even with hostutils installed the luns are shown twice. This server only has one connection to the fc fabric.

Any suggestions?

Regards,

Oliver

Re: Windows Server 2008 R2 sees lun twice... Host utils are installed!

ken_foster — Wed, 29 Dec 2010 18:43:17 GMT

you are having a multipathing issue. you probably have an HA pair, running in single image. without MPIO configured you will always see multiple copies of your LUNs.

Re: Windows Server 2008 R2 sees lun twice... Host utils are installed!

oweinmann — Thu, 30 Dec 2010 08:27:06 GMT

This is the only server in our environment where we have this issue. I remember we had this once on a windows 2003 machine where snap drive wasn't installed. The installation of snap drive solved this issue. I have a virtual 2008 server FC Host utils installed snap drive installed I see the lun only once. The same setup on the physical machine shows the lun twice.

Re: Windows Server 2008 R2 sees lun twice... Host utils are installed!

oweinmann — Thu, 30 Dec 2010 08:54:44 GMT

Problem Solved.

I installed the Windows MPIO Feature, restarted the machine and reconnected the lun.

I don't know why this worked. On the VM there is no Microsoft MPIO feature installed and it works out of the box.

Cheers,

Oliver

Re: Windows Server 2008 R2 sees lun twice... Host utils are installed!

ken_foster — Thu, 30 Dec 2010 14:06:27 GMT

i think i have an idea why the VM didn't have a problem.

The VM is probably accessing VIA iSCSI. the other machine is probably accessing VIA FCP. with FCP the VTIC is a valid path with iSCSI it isn't. Again, this is all supposition since i don't have a diagram but thats how it played out in my head.