[Samba] Windows Server 2019 / Windows 10 LTSC can't access samba shares on Debian stable 4.5.12

[Thomas Glanzmann]

Hello Rowland,

> Stop me if I am wrong (and I often am), but doesn't the 'loopback'
> device do exactly that ? Anything 'lo' receives on its input just gets
> shoved out of its output, or to put it another way, it just goes
> around in a circle, so how does this work with Samba etc ?  Not saying
> it will not work, trying to understand how it works if it does ;-)

lo is a layer 3 (ip) interface. So everything that speaks ip can talk to
it, if you enable routing on the box. So that means in the past I had 32
publically routed addresses in addition to 10.10.10.1 on lo.

# infra.glanzmann.de:
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet 10.10.10.1/32 brd 10.10.10.1 scope global lo:0
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever

# my laptop at home accessing it via vpn:
(x1) [~] traceroute 10.10.10.1
traceroute to 10.10.10.1 (10.10.10.1), 30 hops max, 60 byte packets
 1  192.168.0.3 (192.168.0.3)  1.594 ms  1.677 ms  1.793 ms
 2  10.10.10.1 (10.10.10.1)  15.613 ms  15.698 ms  17.899 ms

Cheers,
        Thomas