Setting MTU on the CSS11500

[tim.metzinger]

Our new WAN provider recommends setting an MTU on our hosts to avoid fragmentation and issues as there are multiple layers of IPSEC encapsulation going on across the WAN.

I can't find a command to set the MTU on the CSS11500 the way I can on all my other Cisco gear. Hoping someone here can help before I go to the TAC.

[Gilles Dufour · Accepted solution]

you can't change the MTU but you can play with the TCP MSS which is all you should need.

CSS11503-2(config)# flow tcp-mss ?

Integer value(Range: 1-1460)

CSS11503-2(config)# flow tcp-mss

Gilles.