ip tcp adjust-mss and ip mtu

[stephen_baugh]

Hi

What's the corrected implementation of the ip tcp adjust-mss and ip mtu commnads.

current setup

site a >E0 >E1---------<E1 <E0 site b

VPN

I have implemented ip tcp-adjust on LAN interfaces(E0),where packets ingress and I have implemented ip mtu on WAN interfaces(E1). Is this correct ?

Thanks in adVANCE

[dathaide]

We have the same setup. What did you set your values at.

[stephen_baugh]

I set E0 wuth tcp mss size of 1402 bytes and E1 IP MTU with 1450 bytes, but users are still having problems

[Richard Burts]

In my experience the correct setting of ip tcp adjust-mss is very dependent on which flavor of IPSec you are running. At a customer site we are running IPSec VPN with ESP running with GRE tunnels. We find that setting the mss to 1375 is effective in solving the fragmentation problems that we were having. Other combinations (ESP or AH, with or without GRE) would probably have different optimum values.

HTH

Rick