Re: [Openvpn-users] Wrong warning about mssfix/fragment

[James Y. <ji...@yo...>]

On Wed, 1 Dec 2004, Claas Hilbrecht wrote:

> With the configuation file attached below I get the following warning in my 
> logfile:
> 
> WARNING: normally if you use --mssfix and/or --fragment, you should also 
> set --tun-mtu 1500 (currently it is 1255)
> 
> But I didn't have a mssfix or fragment option in my configuration file.

Yes, probably that message needs to be changed.  What's it's really trying 
to say is that since mssfix is turned on by default in 2.0 (you can 
disable it with --mssfix 0), you should just leave the TUN/TAP mtu at 1500 
and let mssfix and/or fragment deal with the fragmentation issues.

In 2.0, we found that the vast majority of MTU problems that people tend
to have are solved by simply leaving the TUN/TAP mtu at 1500 and using
mssfix and fragment to limit the size of the UDP packets sent between
hosts.

James