Good day,
We have a 1Gbps link serving about 4000 Wireless internet clients and Peak traffic is about 960Mbps on a CCR1036
Now the question is, will there be any Benefit if I set the MTU on the WAN facing interface above 1500?
Lately I have been experiencing slowdowns in international traffic most notably facebook.
My ccr is connecting to a cisco asr920 with sfp and the cisco is connection to the ISP pop at 10Gbps.
Not sure if this will improve the efficiency of the link
You need to consult your ISP. There will be absolutely no benefit if they don’t support a higher MTU.
Even if the ISP supports it there is no benefit because there won’t be any server that you can reach with
a MTU above 1500 for every link in the path.
MTU above 1500 can be useful when you have a tunneling type of interface that adds extra headers to
every packet. I.e. VPN, PPPoE, MPLS etc. It can be useful to have a slightly higher MTU so that the payload
can still be 1500 bytes. E.g. with PPPoE the MTU will normally be 1492 or 1488 and by setting the link
MTU slightly higher (with the other end supporting it), the MTU of the PPPoE link can be 1500 again,
reducing fragmentation and difficult-to-debug problems that are due to misconfigured firewalls.
However, don’t see it as a solution for problems caused by saturated links, that you apparently have.
Thanks for your feedback.