I've got a host machine receiving IP address from DHCP (192.168.2.x). I have created a guest machine that will have a 172.20.0.x address. I've been able to let them talk together if I use DHCP on the guest as well but then they will be on the same subnet. How do I accomplish network connection between the 192.168.2 and the 172.20.0 networks?
My goal is to have several guest machines in the 172.20.0.x address space that will all talk to each other. So any extra tips on that will be appreciated.
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Hi,
As I understood, you will be having guest virtual m/cs on the 172.20.0.x, and the host m/c on 192.168.2.x.
the guest m/cs will talk to each other since all are on the same subnet.
So, if you let the host m/c to be in the 172.20.0.x subnet as well, and configure it as router and set it as the default gateway for the guest m/cs then they can access other networks reachable by the host m/c.
I forgot to mention that I don't need 172.20.0.0 to be on the internet, so that makes things easier. It is preferable to get access to other hosts on the 192.168.2.x-lan but not vital.
The guests are using the tap0 network device to communicate with the host. tap0 again is linked to eth0 on the host. tap0 will get the 192.168.2.x address via dhcp. How can I add another (static) address to tap0? Will it handle several ip addresses on the same network device?
If you VLAN the two segments, then they will be seen as two network segments.
If you're using ISC's DHCP, you would create a separate subnet for the other address space.
Depending upon the type of device that 'tap0' is, you may be able to use one primary IP address and multiple secondaries (from the same netblock on the same interface).
How do I VLAN the two segments?
All the guests are running on the same machine so I don't understand how I can make two VLAN's.
This is what I do to set up the bridge between the host and the guest:
On the host:
tunctl -t tap0 -u johnny
ifconfig tap0 0.0.0.0 up
brctl addbr br0
brctl addif br0 eth0 tap0
dhclient br0
ifconfig br0 up
ifconfig eth0 0.0.0.0
On the VirtualBox guest:
Network: Adapter 0 -> tap0
Static address: 172.20.0.101 => No connection to host
DHCP address: 192.168.2.x => Connection to host
Can I add an extra address to br0 (which now holds the ip address)? If so, how?
Output from ifconfig on host (lo removed):
br0 Link encap:Ethernet HWaddr 00:15:C5:BF:C5:F7
inet addr:192.168.2.212 Bcast:192.168.2.255 Mask:255.255.255.0
inet6 addr: fe80::215:c5ff:febf:c5f7/6
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2012909 errors:0 dropped:0 overruns:0 frame:0
TX packets:345525 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:454508469 (433.4 MiB) TX bytes:99254194 (94.6 MiB)
eth0 Link encap:Ethernet HWaddr 00:15:C5:BF:C5:F7
inet6 addr: fe80::215:c5ff:febf:c5f7/6
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3415300 errors:0 dropped:0 overruns:0 frame:0
TX packets:539163 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:964883000 (920.1 MiB) TX bytes:133660383 (127.4 MiB)
Interrupt:18
tap0 Link encap:Ethernet HWaddr 00:FF:85:E6:FB:E2
inet6 addr: fe80::2ff:85ff:fee6:fbe2/6
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:137 errors:0 dropped:0 overruns:0 frame:0
TX packets:121311 errors:0 dropped:1573334 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:21227 (20.7 KiB) TX bytes:19177755 (18.2 MiB)
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by: arrkerr1024Posted on 2007-11-29 at 07:16:48ID: 20374137
In short - you need a router. Something has to route between your 172.20.0.x subnet and your 192.168.2.x subnet. You could do the routing on your host OS, or you could do it on your local router - depending on what equipment you have.
You could also just give your host machine a secondary IP that is on the 172.20.0.x subnet - that way it will be on both. But your 172.20.0.x machines won't be able to get on the internet unless something is routing (and NATing) them outwards.