[CentOS] Re: Anaconda doesn't support raid10

Fri May 11 21:05:34 UTC 2007
John R Pierce <pierce at hogranch.com>

Ruslan Sivak wrote:
> John R Pierce wrote:
>>
>>>
>>> Yes, if two disks belonging to the same mirror go down, I lose my 
>>> data.  But if two disks which are not from the same mirror go down, 
>>> I would like to be able to boot up without any problems.  And as 
>>> someone else mentioned, what else am I going to do with those 
>>> 200mb?  I'd rather maintain symmetry and not have to worry which 
>>> disks /boot is on, as I'll know that if the data drive survives, 
>>> then I won't have any problems with the boot drive either.
>>
>> so, is your / on a 4 spindle mirror too?
>>
>>
>>
>> N-way mirrors require every write to be done N times.
>
> No, / is on a 2 raid 1 arrays which are striped using LVM.  And the N 
> times write penalty doesn't really apply to boot, since it rarely gets 
> written to.


so, if the LVM  is built from the 2 raid1 sets md1 and md2, and both 
drives of md1 are down, its down.   ditto if both drives of md2 are 
down.   so why not just put the /boot on the same spindles as md1 ?

btw, LVM isn't really striping, its more like globbing. or scattering.