Gateway VM

mashcaster · Post by **mashcaster** » 10. Jan 2009, 13:25

Is it possible to setup a gateway VM in VirtualBox which will serve as a gateway server for all other VMs?

isama · Post by **isama** » 10. Jan 2009, 15:57

yes, it is possible, you just hook up all vm's to a internal network and one (the vm that will be the router) should be connected to your internal network and to your host (nat/host interface)

I am trying to figure out how to do this on my laptop

mashcaster · Post by **mashcaster** » 11. Jan 2009, 00:16

Please post back if you figure this out.

Post by **Sasquatch** » 11. Jan 2009, 16:35

mashcaster wrote:Please post back if you figure this out.

Why not start yourself? If you know how to setup a gateway on a physical machine, it's not that hard to do it on a virtual one.

If you want it for your physical machines, you need HIF. Else internal networking is what you need. There are plenty of tutorials on the web which describe exactly what to do.

mashcaster · Post by **mashcaster** » 11. Jan 2009, 18:16

Sasquatch wrote:
mashcaster wrote:Please post back if you figure this out.
Why not start yourself? If you know how to setup a gateway on a physical machine, it's not that hard to do it on a virtual one.

If you want it for your physical machines, you need HIF. Else internal networking is what you need. There are plenty of tutorials on the web which describe exactly what to do.

I have tried, but I can't get it to work.

Post by **Sasquatch** » 12. Jan 2009, 22:20

Then you can at least post what you have tried.

mashcaster · Post by **mashcaster** » 13. Jan 2009, 11:08

No prob

I installed debian etch in a VM with 2 NICs and changed the /etc/network/interfaces file to the following:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp

auto eth1
iface eth1 inet static
address 192.168.1.1
netmask 255.255.255.0

eth0 for external connections
eth1 for internal connections

ifconfig returns this

eth0
Link encap:Ethernet Hwaddr 08:00:27:6A:B4:9A
inet addr:10.0.2.15 Bcast 10.0.2.255 Mask 255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets 2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txquenelen:1000
RX bytes:1180 (1.1 KiB) TX bytes:684 (684.0 b)
Interrupt:11 Base address:0xc020

eth1
Link encap:Ethernet Hwaddr 08:00:27:34:99:41
inet addr:192.168.1.1 Bcast 192.168.1.255 Mask 255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets 0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txquenelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:11 Base address:0xc060

lo
Link encap:Local Loopback
inet addr127.0.0.1 Mask 255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets 0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txquenelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

cat /etc/resolv.conf returns:

nameserver 10.0.2.3

echo 1 > /proc/sys/net/ipv4/ip_forward

returns nothing

I can connect to the internet and I can ping to this server from another VM, but I cannot get the other VM to connect to the internet via this gateway VM.

What I am doing wrong?

mashcaster · Post by **mashcaster** » 14. Jan 2009, 17:06

Am I allowed to *BUMP* threads?

Post by **Sasquatch** » 15. Jan 2009, 01:08

What are the network settings on the other VM? How are the two VMs connected with each other?

mashcaster · Post by **mashcaster** » 16. Jan 2009, 22:54

I have the gateway with 2 virtual nics

nic1 = eth0 = net
nic2 = eth1 = internal network
network name = intnet

the standard network pc vm has 1 nic

nic1 = eth0 = internal network
network name = intnet

mashcaster · Post by **mashcaster** » 23. Jan 2009, 16:05

Hesitant *bump*

chronoboy · Post by **chronoboy** » 24. Jan 2009, 00:28

On the Gateway VM there is more to do than just enabling the ip forwarding in the kernel. You will need to change some iptables. Read this very simple HowTo on TLDP.org for configuring your iptables on the Gateway VM:

http://www.tldp.org/HOWTO/Masquerading- ... index.html

Next, on your client VMs, the VMs which connect through the gateway, be sure to assign them each a static IP address and set their gateway IP to your Gateway VM's IP.

Some simple troubleshooting steps would be:

Can you ping the Gateway VM from the client?
When you do a ping to an outside IP address rather than domain name, does it respond?
What DNS servers are set on the client VMs?
Have you attempted a traceroute to the Host?

Give these ideas a try. I know I was able to set-up a Gateway VM before. I used Debian as the Gateway, and had Windows clients connect through it.

Good luck.

mashcaster · Post by **mashcaster** » 24. Jan 2009, 12:20

Is there no "full" guide I can follow which tells me exactly how to set this up from start to finish. I have been trying to join many guides together to get this to work, and it seems I am missing bits out.

Please help.