HPE EVA Storage

MSA2012i: Dual controller = dual target?

 
Marcel van D
Occasional Contributor

MSA2012i: Dual controller = dual target?

I installed a MSA2012i with dual controller. On the initiator, I tried to connect to the target, but it didn't seem to work.

After a long time troubleshooting, eventually even using wireshark to sniff the raw data, I discovered the target name (iqn) had a .a and .b extension for each controller!

I tried to connect to the iqn as found in the web interface, which dosn't show that extension.

Another effect of this, is that my initiator 'sees' 2 LUNs on different targets, making them both available. It is ofcourse the same LUN, accessed through a different controller.

Is there a way to fix this?

Marcel
3 REPLIES 3
Uwe Zessin
Honored Contributor

Re: MSA2012i: Dual controller = dual target?

That is the way the MSA2012i works:

a controller 'owns' a virtual disk and you can map the volumes within the vdisk to both of its host ports. The idea is that you connect both MSA host ports to two different IP subnets and use two NIC ports on the server.

Yes, these are two targets (but they are from the same controller), so you do need a multipath filter in the operating system.
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Marcel van D
Occasional Contributor

Re: MSA2012i: Dual controller = dual target?

Thanks for your swift reply!

I use Linux, and I found some documents about dm-multipath. I'll dive into that, or do you have a better suggestion?

Marcel
Uwe Zessin
Honored Contributor

Re: MSA2012i: Dual controller = dual target?

The device mapper is exactly right:

- Multi-path Device Mapper for Linux Software - Overview
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c01475580

http://www.hp.com/go/devicemapper
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