Boot from MSA2012SA

 
Ambass_GPD
Occasional Contributor

Boot from MSA2012SA

Hi all

In the company we have a MSA2012SA SAN. I have Proliant DL360 G5 multiple servers that are installed SC08Ge HBA controller each.

I want to install W2K8 R2 servers booting from SAN. In the SAN I created a virtual hard disk divided as follows and I assigned all the LUN to the HBA on the test server:

* LUN 2 - 250GB
* LUN 3 - 64GB
* LUN 12 - 128 GB
* LUN 13 - 128 GB
* LUN 14 - 200 GB

When the server starts only appear LUN 2 and 3 on the controller. The Windows installation program shows me the 5 LUN, but only lets me install on the LUN 2 and 3. Why?

In this scenario the installation works without problems if I use one of two LUN showing in the beginning but as I have to install more servers, I probably need higher LUN ID and will not work for the initial installation.

Any ideas?

 
Thanks to all
5 REPLIES 5
Sebastian.Koehler
Honored Contributor

Re: Boot from MSA2012SA

I don't see a real benefit for SAS MSA boot, but anyway. This is most likely because the host is attached to a single MSA SAS port only. If this is the case, the other LUNs are not visible using that path. I would recommend check cabling and use selective LUN presentation from the MSA to make sure only the host sees the required LUNs. How many hosts are attached?

Regards,
Sebastian
Ambass_GPD
Occasional Contributor

Re: Boot from MSA2012SA

Hello

Two controllers are fitted with two ports each in our SAN. In total, four ports.

Each port is assigned to a different server. Three servers in production and test server.

To further detail the topology:

* LUN 3 - Virtual Disk 1 (RAID 10) - Owner Controller A - SAS disk - Visible at start.

* LUN 12, 13 and 14 - Virtual Disk 2 (RAID 5) - Owner controller B - SATA disk - NO visible at startup

* LUN 2 - Virtual Disk 3 (RAID 6) - Owner controller B - SATA disk - Visible to startup

All of these LUNs are assigned exclusively to the test server.

Sebastian.Koehler
Honored Contributor

Re: Boot from MSA2012SA

I've double checked. The MSA2012sa should support ULP and there should be no restriction regarding controller ownership. This means the mapping must be wrong. Please attach the command output or double check yourself.

show hosts
show port-wwn
show volumes
show volume-maps
show host-maps

Regards,
Sebastian
Ambass_GPD
Occasional Contributor

Re: Boot from MSA2012SA

Hi all

Finally, I decided to remove all LUN and start again.

I discovered that, at system startup only see the LUN with an ID that is between 1 and 7. Therefore, the LUN 12, 13 and 14 could not be seen. If I changed the ID to one that was between 1 and 7, worked perfectly to start the machine.


I don't know why? Perhaps the original SCSI standard allowed only 8 devices (7 plus the controller)?

If someone could clarify this point so I could satisfy my curiosity.

regards

 
 
 
 
Sebastian.Koehler
Honored Contributor

Re: Boot from MSA2012SA

You're most likely using a HP SC08Ge HBA SAS HBA / 488765-B21 in your hosts. Must be a restriction of the SAS boot configuration of this specific controller then. If you're doing exclicit LUN presentation on the MSA, LUN IDs does not have to be an issue, since you can assign them per host/connection. Only the boot LUN must be present during boot time. I expect the other LUNs to show up when OS is loaded with full driver stack.

 

Regards,

Sebastian