10G switch drops traffic for a split second
tj at pcguys.us
Tue Nov 29 21:53:23 UTC 2016
I plan on disabling FC on everything tonight, I've done that before but I
want to be sure.
Anything that can be done about the 2 x 1G peers trunking to the 10G router
transition that can be fixed? should I be rate limiting the vlan for the
peers at 1G so the 10G router isn't trying to send more than 1G?
On Tue, Nov 29, 2016 at 1:47 PM, Michael Loftis <mloftis at wgops.com> wrote:
> Yes it is absolutely possible to overrun the buffers. Any kind of
> backpressure (FC) from hosts, or 10G->1G transitions can easily cause
> it. Even if in a 10s window you're not over 1G if the 10G sender
> attempts to back to back too many frames in a row (Like say sendfile()
> API type calls) BOOM, dropping frames in the switch.
> On Tue, Nov 29, 2016 at 1:28 PM, TJ Trout <tj at pcguys.us> wrote:
> > Luke;
> > All l2, no l3. only 4 vlans. 2 peers trunked to a router which trunks
> > to 2 devices (microwave backhauls).
> > Chuck;
> > All ports are 10g except the 2 peers are 1g and trunk back to a 10g port
> > for the router wan
> > No TCN's
> > Brian;
> > I have tried a IBM G8124 and a Ubiquiti ES-16-XG both show same exact
> > across all ports, makes me think it's a config issue. MTU, FC, something.
> > Andrew;
> > I have tried with FC disabled, but I will try that one more time.
> > Mikael;
> > Is it possible to over run the buffers of a 320gbps backplane switch with
> > only 1.5gbps traffic? I think the switch is rated for 140m PPS and I'm
> > pushing 100k PPS
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