Why is ifup not running all of the if-pre-up.d scripts?

Solution 1:

I had this same issue. From what I can tell, if you remove the trailing ".sh" this should work as expected.

sudo mv /etc/network/if-pre-up.d/iptablesload{.sh,}

I can't get to work in ubuntu 20.4 either. script is called iptablesload residing in the if-pre-up.d directory.

I had to do

apt install ifupdown

that should solve on U 20.4, it did for me.