[Gluster-users] about HA infrastructure for hypervisors

[Nathan Stratton]

On Thu, 28 Jun 2012, Brian Candler wrote:

> On Thu, Jun 28, 2012 at 11:25:20AM +0200, Nicolas Sebrecht wrote:
>> We excluded ethernet due to searches on the web. It appeared that
>> ethernet has bad latency.
>
> I read it on the web, it must be true :-)
>
> As I said: don't use 10GE over CAT6/RJ45 (10Gbase-T). That does indeed have
> poor latency.  As I understand it: in order to get such high data rates over
> copper, it has to employ mechanisms similar to DSL lines, like interleaving,
> which means 10G has comparable or even higher latency than 1G.  Switches
> with all 10Gbase-T ports are expensive, only available from a couple of
> vendors, and consume a lot of power.

First gen PHYs did suck a LOT of power, but this has changed. With the 
next gen PHYs the cost of the 10GBase-T switches has also dropped. They 
are now the lowest cost switches out there. I like Arista Networks the 
best, but you can get a switch for well under 10K from guys like 
Interface Masters.

New servers from SuperMicro and others now offer 10GBase-T native 
drastically lowering the cost per port.

> I have been working with Intel X520-DA2 NICs and a Netgear XSM7224S switch,
> and direct-attach cables (3m Netgear AXC763, 5m Intel)
>
> This all works fine, although with older versions of Linux I had to build
> the latest Intel drivers from their website to fix problems with the links
> going down every day or two.

Ya, I ran into a odd problem with my X520s where everything worked except 
VLANs on bonded interfaces. It took me a full day to figure out it was not 
my switch or config, but the stupid ixgbe driver!

><>
Nathan Stratton
nathan at robotics.net
http://www.robotics.net