allebone
Hi there,
I have configured openVPN and it works, but I have a small MTU issue that seems to have stumped me.
If I issue the command on a client pc:
ping -f -l 1464 208.67.222.222
Then it is successful, but
ping -f -l 1465 208.67.222.222
fails. I am unable to work out why. I have set the MTU of the tunnel on the server and client to:
tun-mtu 1500
mssfix
fragment 1440
Which would indicate to me that things should fragment after 1440? I have tried changing the values higher or lower - no effect.
What information should I post to further progress my query and get a hand in identifying my issue?
Kind regards
Pete
maikcat
just curious...
-f has totally different meaning in linux & windows
your OS please?
also,you are pinging 208.67.222.222...
is your openvpn assigns public ips?
can you post your config please?
Michael.
allebone
Hi there,
Apologies, the OS is windows, so the -f is to not fragment. Without the vpn, I can ping up to 1472.
The 208.67.222.222 is just a dns server that I am testing with, it does not assign a public IP.
For the config do you need the servers config or the clients?
Pete
maikcat
i assume that when you are connected all traffic is redirected through
your vpn server...
if you ping openvpn server itself,do you notice the same behaviour?
please post both server/client logs
Michael.
allebone
Hi,
Thanks I think you have helped me to identify the issue. If I perform the same test from the server it also fails on an MTU of 1472 so I believe that you have ruled out the VPN tunnel being the issue, and the issue is now on the server side.
Since that is the case, you have successfully demonstrated that the VPN is working as intended.
Kind regards
Pete
