How-To: Create a NethServer instance in VirtualBox machine

I have an issue on a debian host with virtualbox5, In fact when I set the vboxnet1 to an IP of my network, the IP is reachable but it goes to the host and not to the VM...I need to dig a bit

here the ifconfig on my host which runs virtualbox...fun

# ssh root@192.168.xx50
The authenticity of host '192.168.xx.50 (192.168.xx.50)' can't be established.
RSA key fingerprint is 5f:7b:d0:2f:88:cf:c0:76:9b:6a:0e:c7:c1:b7:2f:2b.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.xx.50' (RSA) to the list of known hosts.
root@192.168.xx.50's password: 
Linux htpc-server 3.2.0-4-amd64 #1 SMP Debian 3.2.71-1 x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Mon Nov 16 16:01:02 2015 from leo.lan
root@htpc-server:~# ifconfig
eth0      Link encap:Ethernet  HWaddr 94:de:80:bf:d6:56  
          inet adr:192.168.xx.100  Bcast:192.168.xx.255  Masque:255.255.255.0
          adr inet6: fe80::96de:80ff:febf:d656/64 Scope:Lien
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2687901 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3342484 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 lg file transmission:1000 
          RX bytes:744051082 (709.5 MiB)  TX bytes:1629300672 (1.5 GiB)
          Interruption:74 Adresse de base:0xc000 

lo        Link encap:Boucle locale  
          inet adr:127.0.0.1  Masque:255.0.0.0
          adr inet6: ::1/128 Scope:Hôte
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:3331679 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3331679 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 lg file transmission:0 
          RX bytes:41995499667 (39.1 GiB)  TX bytes:41995499667 (39.1 GiB)

vboxnet0  Link encap:Ethernet  HWaddr 0a:00:27:00:00:00  
          inet adr:192.168.56.1  Bcast:192.168.56.255  Masque:255.255.255.0
          adr inet6: fe80::800:27ff:fe00:0/64 Scope:Lien
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:724 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 lg file transmission:1000 
          RX bytes:0 (0.0 B)  TX bytes:83131 (81.1 KiB)

vboxnet1  Link encap:Ethernet  HWaddr 0a:00:27:00:00:01  
          inet adr:192.168.xx.50  Bcast:192.168.xx.255  Masque:255.255.255.0
          adr inet6: fe80::800:27ff:fe00:1/64 Scope:Lien
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1122 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 lg file transmission:1000 
          RX bytes:0 (0.0 B)  TX bytes:106412 (103.9 KiB)

root@htpc-server:~#