There is a host on Linux, there are virtual machines, access to the Internet via PPPoE, without a router! the host does not see the virtual machine, how to solve it with minimal means?

Question

linux

in fact, the experiment is far from the first ..
in the presence of a banal router, there are no problems of this kind at all. all routers known to me had a feature something like DNS relay. it was enough to make a network bridge (aka a bridge) to a network card that is in the router, in the guest to announce the grid as home, and everyone was happy.
when PPPoE has to be raised directly on the network port of the motherboard, the Internet has to be distributed to guest systems through NAT (virtualbox). in order to somehow establish communication, I try to raise the second stem interface at a party, in the virtual network of VirtualBox itself.
but in the end, the host, which is wine10, which is yubunta, which is fedora .. does not see guests. his guests resolve by name and ping. one does NOT resolve names, but still pings via direct ip
is there a simple enough way to "open the eyes" of a host?
edit!
Windows guests have 2 network interfaces:
1 - NAT
2 - VirtualBox virtual network, which is forced to be set as "home" through network name policies. network notification is enabled. each other (well, at least screw guests) see at once.
another edit!
there may be more guests - Linux, androids, anyone. the change can be frequent
(do not offer hosts for this reason)
on the fedora, the vboxnet0 connection is now up, the firewall zone is home, but "not alle" ((
at the same time, in principle, it pings
on the assigned tasks via the IP address, in this chicken coop, it is necessary that the host also sees guests.
If anyone has dealt with similar situations - I will be grateful for the advice!
ps It's not the first year in Linux, but so far I've only figured out the desktops more or less, I haven't mastered the network features yet, call

Answer 1

1 - the question is closed. the ideal answer - buy a pancake router
2 - from hosts it would be desirable to elude. but I had to put up with it (DNS smoking will take longer. The virtual router will also have to be smoked. And even raise the machine)
3 - but it turned out to remove at least half of the manual work - you don’t need to register ip when visiting. we drive the virtualbox adapter into link local and the addresses are generated automatically. at what always same, at least for ipv6 it is guaranteed. the only trouble is that for ipv6 you will have to add a static route (pinging only with an explicit indication of the adapter ping fe80::6965:ccb2:3286:bc78%vboxnet0
) but this is definitely a matter of technology (google)
thanks to all kind people!
not very kind - also a fair wind

Answer 2

In the virtual machine settings, enable the second network adapter with the Host-only adapter setting.
If it rises via vagrant -
config.vm.network "private_network", ip: "192.168.33.30"