Page 1 of 1

tun-mtu, fragment and mssfix: Client, Server or Both?

Posted: Thu Jul 16, 2015 5:55 pm
by MBNH
We have server-side conf files and client-side ovpn files. If I want to troubleshoot an MTU issue, do I use the tun-mtu, fragment and mssfix parameters in the client or server config, or both?

Re: tun-mtu, fragment and mssfix: Client, Server or Both?

Posted: Fri Jul 17, 2015 11:58 am
by Traffic
Use --fragment and --mssfix in both your configs as these cannot be pushed.

Also try:

Code: Select all

mtu-disc yes
mtu-test
in both your configs.

This thread may help:
confusion over udp "fragment"

Re: tun-mtu, fragment and mssfix: Client, Server or Both?

Posted: Mon Feb 22, 2016 8:58 am
by bmarien
Just wondering,

Can we use the output of the test in some script? Or can the result be written to file?


Thanks

Re: tun-mtu, fragment and mssfix: Client, Server or Both?

Posted: Tue Feb 23, 2016 12:31 pm
by Traffic
bmarien wrote:Can we use the output of the test in some script?
Unlikely, as you cannot pump this back to openvpn ..
bmarien wrote:can the result be written to file?
It is written to the openvpn log ..