How to set permanent mtu size for ppp0

Solution 1:

I've tried to apply Farshad's solution on ubuntu 16, and it wasn't working.

Only small fix was needed there - remove sudo inside your script, because everything inside /etc/network/if-up.d/ dir is already run as root user

#!/bin/sh

if [ "$IFACE" = "ppp0" ]; then
    ifconfig ppp0 mtu 1300
fi

Solution 2:

As I said at this Link

You can make your custom script

at this address : /etc/network/if-up.d,

#!/bin/sh

if [ "$IFACE" = "ppp0" ]; then
    sudo ifconfig ppp0 mtu 1300
fi

finally make executable and enjoy from your life ...

Solution 3:

You can define the mtu setting inside the /etc/ppp/options file. The setting should already be present in the options file but should be commented out by default.