[mythtv-users] Why RAID 5 stops working in 2009

[John Finlay]

David Brodbeck wrote:
> On Fri, October 24, 2008 1:57 pm, jedi wrote:
>   
>> On Fri, Oct 24, 2008 at 01:54:11PM -0700, David Brodbeck wrote:
>>     
>>> On Fri, October 24, 2008 12:45 pm, Mache Creeger wrote:
>>>       
>>>> Should we just pray that although the statistics say otherwise,
>>>> native RAID5 on Linux will not self-destruct when using many large
>>>> capacity drives?
>>>>
>>>> Any ideas?
>>>>         
>>> Don't use RAID 5.  Use RAID 10 instead.  See this page for a humorous
>>> take
>>> on why:
>>> http://www.miracleas.com/BAARF/BAARF2.html
>>>       
>>     ...I've been thinking not RAID 10 but LVM on top of RAID1.
>>     
>
> Sure, that's basically the same thing.  RAID 10 just means you're taking a
> bunch of RAID 1 mirrored pairs and striping data across them RAID 0 style.
>  RAID 01 is the opposite; it's taking two identically-sized RAID 0 stripes
> and mirroring them.  Functionally the two are equivalent, except I think
> RAID 10 has some advantages when you have to rebuild.
>   
I think raid10 has better failure characteristics i.e. if a disk on 
raid01 fails it knocks out the whole raid0 its in so only half the disks 
are still working while with raid10 if a disk fails then only one disk 
is knocked out and the other disks are still working.

John