Thanks Mr. Brandon for the response/feedback. Rgrds
17.06.2024 22:08 tarihinde Brandon Martin yazdı:
Is something out of your control also breaking PMTU discovery (e.g.
blocking all ICMP traffic)? With working PMTU discovery, this issue
should resolve itself in the ingress direction.
You should also set the MTU properly on your PPPoE tunnel interface.
If the setup inherits properly from the parent interface's MTU, this
should again be automatic, but I've observed a lot of PPPoE stacks
don't necessarily do that (not that I've used PPPoE in a hot minute).
That will get mean PMTU discovery between things on your LAN and the
Internet happens right at your Internet edge in the egress direction
and therefore doesn't incur Internet latencies. If the "clamp MSS to
PMTU" is working, this probably means you have it right since that's
usually where the rule gets its PMTU (not actual end-to-end PMTUD),
but I don't know Microtik for sure.
Clamping the MSS to the known PTMU will fix the opposite direction in
cases where PMTUD is broken. That's basically why it exists.
