Virtualmin GPL overwrites /etc/network/interfaces settings when adding/removing virtual hosts


I’m running the up-to-date Virtualmin GPL on Ubuntu 14.04.3 and have the problem that for IPv6 to work on my root server, the file at /etc/network/interfaces needs to have these two lines added in the inet6 section :

up ip route add default via fe80::1 dev eth0 down ip route del default via fe80::1 dev eth0

But every time I add or delete a virtual host, Virtualmin overwrites the file at /etc/network/interfaces causing IPv6 to become inaccessible.
To make things worse, I haven’t been able to find any way to apply changes to /etc/network/interfaces via SSH without rebooting the whole server.
(“sudo service networking restart” no longer works with Ubuntu 14.04)

It would be great if Virtualmin would respect any customisations of /etc/network/interfaces and only add/remove IP address lines in it without overwriting user-made changes.

Secondarily, how does Virtualmin apply changes to /etc/network/interfaces without rebooting? I could at least use the same method to restore the missing settings without rebooting!

Many thanks !

I think the cause here is that Webmin expects that you will specify the default gateway using the gateway fe80::1 line in the IPv6 block for eth0 in the interfaces file, rather than having special up/down commands to add routes.

Many thanks ! I’ll try that - do you have a hint as to how to apply changes to the interfaces file via ssh without having to reboot Ubuntu 14.04 ?