[f-nsp] Does MLX "show interface" account for Ethernet Preamble and IFG

[Nick Hilliard]

On 10/10/2011 16:56, GRADY NEELY wrote:
> This sounds like the link may have been peaking over 1Gig, and
> measurements were only taken every minute.  My question is this, does
> the "Show interface" output (and by extension, the if-mib) account for
> the MAC preamble and IFG?

No, it doesn't but that's probably not the problem.  Probably your customer
is seeing the effects of microbursts on the interface, where the
instantaneous load can dramatically exceed 1G for very short periods,
bursting the port buffer and consequently dropping packets.  You need to
check the packet drop counter on the output interface with the high load to
see what's happening.

This topic comes up very regularly.  For IPTV you need large port buffers
and possibly careful QoS management, depending on your requirements.

Nick