IOS(XR) MTU

There were a number of TCP enhancements that went in around the 5.1

timeframe which impact the way window scaling works as well.

Also, do you have path-mtu enabled on all the devices?

on XR you want something like this:

tcp selective-ack

tcp window-size 65535

tcp path-mtu-discovery

IOS:

ip tcp path-mtu-discovery

ip tcp window-size 65535

http://www.cisco.com/c/en/us/support/docs/ios-nx-os-software/ios-xr-software/116350-trouble-ios-xr-mtu-00.html

> interface GigabitEthernet0/0/1 no ip address

>

> service instance 100 ethernet

> xconnect x.x.x.x {VC_ID} encapsulation mpls mtu {}

>

> But If I configured the below

> l2vpn xconnect context {NAME}

>

> There is no option for the MTU under it

 

 

You have to configure it on the pseudowire interface:

http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_l2_vpns/configuration/xe-3s/mp-l2-vpns-xe-3s-book/mp-any-transport-xe.html#concept_B3B085AFF0384B5C867E3EF9A4C58564