Openvpn mtu-test info This connection is unable to accomodate a UDP

[periko]

I upgrade my system to the latest 2.1.5 i386.

My ovpn logs show me this:

openvpn[8177]: NOTE: Empirical MTU test completed [Tried,Actual] local->remote=[1557,1445] remote->local=[1557,1557]
openvpn[8177]: NOTE: This connection is unable to accomodate a UDP packet size of 1557. Consider using –fragment or --mssfix options as a workaround.

I have 2 clients site2site 1 use PPPoE, the other is DHCP.

After running the test both logs show the same values for my 2 clients.

remote=[1557,1445] remote->local=[1557,1557]

Can someone explain me this info? and how can I start playing with this values for:

fragment
mssfix

This parameters goes just in the server side?

Any help will be appreciated, thanks.