Cannot boot from software RAID with 2TB disks

[Chan Chung Hang Christopher]

Matthias Brennwald wrote:
> On May 14, 2010, at 2:26 PM, ubuntu-users-request at lists.ubuntu.com wrote:
> 
>> Matthias Brennwald wrote:
>>> On May 13, 2010, at 3:56 PM, ubuntu-users-request at lists.ubuntu.com wrote:
>>>
>>>> Matthias Brennwald wrote:
>>>>> On May 13, 2010, at 5:44 AM, ubuntu-users-request at lists.ubuntu.com wrote:
>>>>>
>>>>>> I have also been tried this configuration except with 2x250GB SATA drives
>>>>>> with software RAID1 on Ubuntu 10.04. The installation went fine except that
>>>>>> the server is unable to boot. I cannot get GRUB to install correctly. Does
>>>>>> anyone have a solution?
>>>>>>
>>>>>> Nigel
>>>>> Thanks for this info. I don't have a solution (yet), but at least we now know the problem is not (only) related to the size of my disks (2TB).
>>>>>
>>>> Yours is due to the Debian installer not supporting making a bios_boot 
>>>> partition under the GPT scheme of things for embedding grub.
>>> I believe I do not understand this (I am a noob). How can I get around this flaw in the installer? Boot from the Live CD, install parted, and use this to set up my software RAID from the Live CD environment before installing the system? Do I have to make the bios_boot partition there, too? Or what?
>>>
>> The GPT scheme does not leave space for grub to embed itself like the 
>> pcdos scheme does. Which is why you have to create a bios_boot partition 
>> in the GPT scheme to provide a place for grub to embed itself.
>>
>> grub can still work without that but it is like playing Russian roulette 
>> because it will have to create a file listing the location of blocks 
>> where its code is stored and hope they are never moved.
>>
>> Hmm, the alternate installer aka Debian installer apparently should have 
>> already got this licked according to the post below...
>>
>> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=491376
>>
>> This guy worked around the installer...I am not that familiar with the 
>> debian-installer, with anaconda Alt-F2 would give me a shell, I 
>> remembered something similar with debian-installer
>>
>> http://osdir.com/ml/grub-devel-gnu/2009-08/msg00254.html
>>
>> But yes, your idea of creating the partitions (especially the bios_boot 
>> partition and using parted to mark) in the LiveCD environment before 
>> loading the installer should do too.
> 
> Ok, I believe partitioning within the Live CD environment would be the easiest for me (I do not fully understand all the tech talk at the above links).
> 
> Assuming I can successfully install Ubuntu to one of my disks (no RAID at all), would it be wise to just copy the the partition set up of this disk to the remaining disks? If "yes": should I do this manually or is there an easier way to do this? Doing things manually has the potential for screwing up (partition sizes, file system types, flags, etc.)...
> 

If you want to run a 5 disk mirror (provided you did say raid1 mirror 
but single disk during the install) you could try but there would some 
challenges perhaps with the uid I think. I think it would be easier to 
make a mirror with just one initial member and let md handle the syncing 
to the other four disks.

If you still want raid5, that ain't going to work I am afraid.