Re: Real application clustering in postgres.

On Fri, 2020-03-06 at 03:25 -0600, Ron wrote:
> > RAC is not really a high availability solution: because of the shared
> > storage, it has a sibgle point of failure.
>
> This is utter nonsense. Dual redundant storage controllers
> connected to disks in RAID-10 configurations have been around for at
> least 25 years.
>
> Oracle got it's clustering technology from DEC, and I know
> that works. Cluster members, storage controllers and disks have all
> gone down, while the database and application keep on humming along.

I am not saying that it is buggy, it is limited by design.

If you have mirrored disks, and you write junk (e.g, because of
a flaw in a fibre channel cable, something I have witnessed),
then you have two perfectly fine copies of the junk.

I am not saying the (physical) disk is the single point of failure, the
(logical) file system is (Oracle calls it ASM / tablespace, but it is
still a file system).

Yours,
Laurenz Albe