Hi all,
Assuming typical MPLS network running L2VPNs and L3VPNs, how do you
configure MTU values for core interfaces? Do you set interface (L2) MTU,
MPLS MTU and IP MTU separately?
Do you enable PMTUD for TCP based control plane protocols like BGP or LDP?
Thanks!
__
We set the 'physical' MTU (In IOS-XR+Junos L2 but no CRC is in this
humber) as high as it went when the decision was made. Today you can
do I think 10k in Cisco8k and 16k in Juniper. We do not seet MPLS or
IP MTUs separately in Core. On the edge you should always set L3 MTU,
because you want to
Hi Saku,
I am embarrassed to say, but I _just_ found out, like literally weeks
ago, that Junos BGP TCP window is 16kB, I did also find hidden command
(https://github.com/ytti/seeker-junos) to bump it up to 64kB. I am
working with JNPR to have public documentation for the hidden command
to improv
Hi Saku,
> To handle NIC received packets you can do two things
>
> a) CPU can get interrupt, and handle the interrupt
> b) Interrupts can be disabled, and CPU can poll to see if there are
> packets to process
>
> The mechanism a) is the norm and the mechanism b) is modernish. To
> improve PPS per
> https://www.rfc-editor.org/rfc/rfc8654.html
Thanks!
> But it was [8936, 1240].min - so it was 'negotiated' here to the
> smallest? If you change the 8936 end to 1239, then that will be used,
> regardless who starts it.
Yes, but why would XR advertise 1240 if I'm using 'tcp mss 8936' for that
> I may have misunderstood you. Ddi you have 8936 configured on both
> ends? I thought you had only 8936 on the CSR.
>
> How I understood it:
>
> *Dec 8 11:17:15.453: TCP0: Connection to 12.0.0.7:179, advertising MSS
8936
> *Dec 8 11:17:15.456: TCP: tcb 7FFB9A6D64C0 connection to
> 12.0.0.7:179,
I did some benchmarking back in ~2008-2009 (with 12.2.31SB and 12.2SR,
who still remembers that?), and we (Cisco) fixed numerous non optimized
paths in the routing code. But that was over a decade ago, so I’ll
limit bragging about it ;) There are two presentations, quoted from
about that time I ca
