Configuring emulex BIOS to boot from SAN

[devs159]

Hi,

We have an issue where we're trying to boot from SAN on 2 hosts (ESXi 5.0 Update 1) and the boot from san LUN number is configured to 100 (LUN0 is already in use by the EMC array). The shared LUN's for the ESXi hosts start from 1 and when the host tries to boot into ESXi it fails. You can specify the LUN number in HEX format (64 should correspond to LUN100) through the emulex BIOS but this still fails when I enter the HEX number.

Any suggestion from similar set-ups?

Thanks

[kastlr]

Hi,

usually it's not a problem with EMC arrays to reuse LUN ID 0 multiple times.

Depending on the kind of array you're using it could be configured differently.

With CX/VNX, create a SG (storage group), add your LUN's and assign the LUN ID's as needed.

Each SG should contain (and could) contain an ALU device with an assigined HLU of 0.

With Symmetrix, you could use masking groups to present symm devices to a host with a LUN ID of 0.

So reconfiguring your storage array to present a device with LUN ID 0 would be the best way to avoid these problems.

Regards,

Ralf

[elxaamaya]

Hi,

to add to the thread but not sure what Fibre channel adapter or model number we are talking about. Also want to make sure you have the latest FW and BootCode installed. I am not sure if it the boot code has been applied. Boot code with the existing BIOS allows the system to boot from a connected fibre channel drive. In addition, there's documentation from both VMware and Emulex that show how to configure a Boot from SAN. Hope this helps.

http://pubs.vmware.com/vsphere-51/index.jsp?topic=%2Fcom.vmware.vsphere.storage.doc%2FGUID-8AE88758-...

The Implementers Lab has a few whitepapers with the steps on BfS process.

http://www.implementerslab.com/solution-implementers-series/deployment-guides.html

BootCode Manual just in case and it also has some info on BfS.

http://www-dl.emulex.com/support/hardware/documentation/fc/11-12/bootcode.pdf

if you still have issues in getting BfS to work after updating the fw and bootcode, give Emulex support a call to make sure you have a working adapter.

tech.support@emulex.com

[devs159]

It wasn't possible to use LUN0 in the Emulex configuration as a gatekeeper LUN was already using LUN0. As the shared LUN's started at LUN100 we tried specifying the LUN number via hex in the emulex HBA's but without success.

The hosts would only boot when the shared LUNs were not visible to the host and it could only see LUN100 (boot LUN) & this was without any changes to the Emulex BIOS. It would probably have worked if we used re-numbered LUN1 to number not in use and then assigned LUN1 as the boot from SAN volume. It wasn't an issue with the VMware configuration as it didn't even try to boot since it would have to access the boot LUN firstly (once you've a remote syslog configured it would output logs with a failed boot).

A local disk configuration setup in the end due to time constraints in resolving the issue. I'm sure we would have resolved the issue if we set-up the same config. in a test lab.

[elxaamaya]

Thank you for your message. I will be out of the office At VMware with minimal access to email or vmail. I will be returning back to the office Friday 21st.

For any urgent issues please call my cell phone 408-410-2773

Thank you

Alex Amaya

[devs159]

Just to add to my last comments, we know the boot from san worked when there was no shared LUNs present & for some reason entering the LUN number in the emulex BIOS didn't work for some reason.