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I'm starting a VPN connection using Network Manager. Once the connection is established I have to change MTU in order it to work properly. For example:

sudo ifconfig ppp0 mtu 777

It is very annoying to execute this command every time I open a VPN connection. Is there any idea to create a script that would execute this command automatically once the connection is established (ppp0 interface is up)?

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up vote 7 down vote accepted

Create a script in /etc/network/if-up.d, containing


if [ "$IFACE" = "ppp0" ]; then
    ifconfig ppp0 mtu 777

and make it executable.

share|improve this answer
Thank you. It works! – Andreas Sep 10 '11 at 8:35

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