Tyler wrote:
> Eyal Lebedinsky wrote:
>
>> Executive summary: it is not the TX4. It is not really raidreconf.
>> You must specify the parity-algorithm in raidtab because the
>> raidreconf default is not what one expects.
[trim]
> Nice work Eyal :)
>
> Now all we need is a patch for raid-reconf to fix default behaviour? :D
>
> Regards,
> Tyler.
Well, as simple as this looks, I have little understanding of what
goes on here. For example, looking at raidtools-1.00.3, I see this:
This is defined in three source files, as well as in common.h
# define RAID5_ALGORITHM_LEFT_SYMMETRIC (2)
In prconv.c, readboth.c, rrc_raid5.c and sectors.c the algorithm
hard set:
static unsigned long
raid5_compute_block (... whatever ...)
{
int algorithm = RAID5_ALGORITHM_LEFT_SYMMETRIC;
...
/* Select the parity disk based on the user selected algorithm */
switch (algorithm) {
I cannot see how 'algorithm' can be altered at all here, so I do not
think that these programs respond to the raidtab algorithm at all.
In short, maybe raidreconf should not only default to left-symmetric
but refuse any other algorithm if it needs to cooperate with the other
programs here.
Better someone who knows this area does this. The actual setting
of a default is simple.
--
Eyal Lebedinsky (eyal@xxxxxxxxxxxxxx) <http://samba.org/eyal/>
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