Invalid GPT backup header

[dweimer]

On 2012-07-09 15:11, dweimer wrote:
> I have had a few virtual machine installations come up with "gptboot:
> invalid GPT backup header" error message while booting. (some
> immediately on first boot after install) They still boot fine, and 
> run
> without problems, but I would like to find a way to fix the problem.
> Does anyone know how you can write a new GPT backup header to the
> partition table.  I have even gone to the extent of adding a second
> virtual disk, using gpart to create a partition table and then add 
> new
> partitions and setup bootstrap then use cpio to copy data over and
> switched the drive SCSI IDs within the virtual machines configuration
> to boot from the second drive instead.  Still same error message when
> booting off the new drive.  I did however leave out the size option
> when creating the last UFS partition so it may have filled to the end
> and overwrote the backup GPT table.
>
> I have searched online for a solution to recreating the backup GPT
> header from the main header, but I have been unable to find anything.
> Not sure if I am missing something simple, if no one else has had 
> this
> problem, or if others are just ignoring it since their system works
> even with it?  All the machines with the problem are VMware hosted
> machines, some on ESX, and some on VMware Workstations.

Just a quick update in case someone else runs into this and finds this 
thread, this problem maybe related to a quirk of some sort in the older 
version of VMware workstation I am running on my work laptop its running 
version 6.5 (can't get boss to approve upgrade as the other admins have 
just decided its better to test on the ESX servers instead of their 
local machines, which I don't agree with) I had an urgent need to use a 
this machine to put a temporary work around in place on another problem 
and used vmware converter to migrate it from my workstation to the ESX 
servers.  No more invalid backup GPT message when booting the one copy 
on the ESX servers.  I am going to manually copy the files for this VM 
to the version 8 workstation installation on my home machine and see if 
that one does or doesn't show the warning on boot, to attempt to better 
narrow down this cause.

-- 
Thanks,
    Dean E. Weimer
    http://www.dweimer.net/