Hello,
I have a problem for configuring a pppoe interface by setting default-route auto or default-route forces the parameter is not used. When changing the state of the pppoe interface, the default route is deleted (default route define in protocols static route) and not recreated.

Here is the info I have:

vyos@vyos# show interfaces pppoe pppoe0
authentication {

password xxxx
user [email protected]

}
default-route auto
dhcpv6-options {

pd 0 {
    interface eth0.3 {
        address 100
    }
}
pd 1 {
    interface eth0.4 {
        address 100
    }
}

}
ip {

adjust-mss clamp-mss-to-pmtu

}
ipv6 {

address {
    autoconf
}
adjust-mss clamp-mss-to-pmtu

}
mtu 1492
source-interface eth1

And the result after commit :
cat /etc/ppp/peers/pppoe0
....
nodefaultroute
noreplacedefaultroute
....