Re: Tyan Thunder MB for postgres server

Hi William,

> SOmething to think about. Let's suppose a channel/cable completely dies.
> How would you protect against it? Split a logical mirror device over 2
> channels.

This effectively implements RAID 0+1, right? RAID 1 (mirroring) over RAID 0
striped volumes. I can certainly see your point regarding the redundancy of
the controller channels, but my understanding is that (apart from that) RAID
0+1 is less robust that RAID 10 regarding disk failures. Presuming that the
system will continue to operate even in the event of 1 channel failure, it's
still not a clear choice. Does that seem like a reasonable assessment?

> Another trick I've started doing with my MegaRAID setups is mirroring in
> hardware but striping in software.

Yeah, that is a good point. I havn't decided either way but I consider that
a viable option.

If you were building this system now, and want the option of buying the same
disks in 3 years time, do you think it would be a bad idea to go for the
~40GB size? Maybe the next size up would be better, though we don't actually
need the extra space.

If you have any specific recommendations (for or against) specific
drives/manufacturers, please let me know.

Also, someone asked me what happens if one of the CPUs fails on this system,
will the system continue to operate on 1 CPU. I havn't really considered
this, and have never read anything either way, so my assumption is "no, it
won't". Any comment?

Thanks again
Iain