HAST considarations

[Daniel Kalchev]

On 06.02.12 13:43, Damien Fleuriot wrote:
> This issue is due to a bug in OpenBSD 3.8's implementation of CARP.
>
> It triggers if you have net.inet.carp.preempt=1 on the node.
>
> If the sysctl is set, the interface assumes MASTERship immediately upon
> being brought up, then yields in the presence of a better master.

I know about this patch, but on my systems

net.inet.carp.preempt=0

I was running 8-stable, now 9-stable on these servers and observe the 
same behavior.

George Kontostanos:

My setup has 1G interfaces for the CARP/Internet and 10G interfaces for the backend/HAST. I am doing hast over the 10G interfaces. For a system with part of 10k SAS drives, and ZFS mirror (each element of the mirror is an HAST provider), running bonnie++ I see about 100MB/sec flow to the secondary HAST and that about saturates the disks as well (50-60MB/sec.. should have been better)
I had earlier experiment with 4 drives in each system and that replicated at up to 230 MB/sec.

Daniel