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ESXI 5.1 Cisoc UCS Boot From SAN

compdigit44
compdigit44 asked
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My company has just started to get Cisoc UCS B-Series servers and we are going to set them up as boot from SAN. We have a seperate storage group than managed every aspect of or SAN. I personally have never setup ESXI to boot from SAN. I have aready read the following article but have the following question.

1) WHen you present LUN0 to one host ato install ESXI on do you then present the same LUN to other server so they  can boot from the same image.

2) If all host boot from SAN and do not have local storage where are settings like network, host name etc stored. If the host is reboot they would be lost since it would be in memory only. Does the UCS manager help with this at all? We are not using Auto Deploy
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Andrew Hancock (VMware vExpert / EE Fellow)VMware and Virtualization Consultant
Fellow 2018
Expert of the Year 2017

Commented:
We think it's rather old fashioned these days to BOOT from LUN, it was something that was done a lot in the "old days" of fibre channel, before VMware, released the Embedded Version of ESXi, e.g. the ability to use USB Flash drives or SD cards in servers, that did not have any local storage for the OS.

It was very common with ESX (not i), some organisation still boot blades from LUN0, using ESXi.


1. I'm afraid not. Each ESXi server must have it's own unique LUN0. If you configure multiple ESXi hosts to share the same BOOT (LUN0), image corruption will occur.

2. not applicable, as all hosts need their own BOOT LUN.

You will need multiple LUNs, e.g. LUN per ESXi host.
Zacharia KurianAdministrator- Data Center & Network

Commented:
WHen you present LUN0 to one host ato install ESXI on do you then present the same LUN to other server so they  can boot from the same image

Very bad idea. You will face image corruption. You can test  such kind of scenario and see it yourself.

Zac.

Author

Commented:
Thanks for the great replies. So if each host has it own boot volume all host specific settings are stored on LUN0 correct. We actually have a consultant coming in this week to setup our first three UCS blades. I know our exist IBM blades have flash option I am not sure if UCS has this as well.


Anything we should be aware of went setting up the UCS server with ESXi. Does any one know what HBA card's they use?
VMware and Virtualization Consultant
Fellow 2018
Expert of the Year 2017
Commented:
Correct, each host will have it's own boot volume, LUN0. The entire OS is installed on LUN0, just as if it was a local hard disc, SD flash card, or USB flash drive.

BOOT Priority set to HBA, and HBA set to LUN0.

The Cisco bible and handbook is here....including an option on Installing VMware vSphere ESXi on a Bootable SAN LUN

http://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/os-install-guides/vmware/b_C-Series_VMware_Install/CSERIES-VMWARE_chapter_011.html

http://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/os-install-guides/vmware/b_C-Series_VMware_Install.pdf

Another Reference....

http://jeffsaidso.com/2010/11/boot-from-san-101-with-cisco-ucs/

As for HBA, could be Qlogic, or Eumlex, or convered Cisco adaptor, depends, what you've got!
Zacharia KurianAdministrator- Data Center & Network

Commented:
Andrew,

We do expect an article from you on Cisoc UCS-Vmare configuration.

Zac.