See two uninitialized disks

[WCzar]

Created a vdisk and host for 900 GB raid 5 on our EVA3000. Presented the disk to the W2K3 server. When I did a rescan within disk administrator it displays (2) 900 GB unitialized disks. Tried rescan again and doubled checked the config on the EVA3000. Have not rebooted the server. Can someone help? Thx.

[WCzar]

Forgot to mention that I have not yet converted the disk to dynamic because I was not expecting to see two unitialized disks in Windows Disk Management.

[Uwe Zessin · Accepted solution]

'out-of-the-box' Windows does not know how to deal with multiple paths. The solution is a multipath filter (commonly called MPIO). There are two different filters available, depending on the EVA controller firmare:

- HP MPIO Basic DSM (Device Specific Module) for Windows for EVA3000/5000 VCS 3.xxx Disk Arrays:
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=18964&prodSeriesId=421492&prodNameId=421494&swEnvOID=1005&swLang=13&mode=2&taskId=135&swItem=co-54265-1

('basic' means it does not have any management functions)

- HP MPIO Full Featured DSM (Device Specific Module) for EVA3000/5000 VCS 4.xxx Disk Arrays
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=18964&prodSeriesId=421492&prodNameId=421494&swEnvOID=1005&swLang=13&mode=2&taskId=135&swItem=co-68693-1


The full featured can be enhanced with a MMC plugin:

- HP MPIO DSM (Device Specific Module) Manager for Full Featured DSMs
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=18964&prodSeriesId=421492&prodNameId=421494&swEnvOID=1005&swLang=13&mode=2&taskId=135&swItem=co-71732-1


and, if the database is not overloaded, you can even get documentation:
http://h20000.www2.hp.com/bizsupport/TechSupport/DocumentIndex.jsp?contentType=SupportManual〈=en&cc=us&docIndexId=64179&taskId=135&prodTypeId=18964&prodSeriesId=421492

[WCzar]

So then MPIO DSM must be installed on the Windows server regardless of there being only one fiber connection back to the EVA? I was thinking MPIO was necessary only when multipathing was being used.

[Víctor Cespón]

Even if the host has only one FC cable, connected to one switch, both EVA controllers are connected to that switch, so the server sees each vdisk through 2 paths.

Hence, you need MPIO multipathing software.

[Uwe Zessin]

Well, you can set up zoning in the switch so that the server has access to only one EVA controller port.

There is a minor thing: with VCS V3 the EVA is an "active/passive" storage array and you need to set up the zone so that the server has access to the controller which manages the virtual disks (he must manage all of them: assign vdisk management control on the EVA).

You can still use MPIO with one adapter port and it will take care about which controller to talk to. And the system even has small redundancy: should one controller fail, the server can still access the data through the surviving one.

[WCzar]

Went with one fiber connection back to the EVA3000. Installed MPIO\DM version 4 from HP. Now see the SAN disk as one 900 GB disk in Windows Disk Management. All is working well - thanks to all who kindly offered advice.

[WCzar]

Question answered. Thx.