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I am desperately trying to run untangle 10 as a guest in kvm. My host system is debian 7.2

My problem is that I am unable to configure bridges/(virtual)NICS which are successfully identified by untangle. I would like to have two NICS in untangle. One for the internet connection and the other one for the internal network.

I already read several tutorials and how-to's and as far as I understood I have to configure network bridges.

I tried to configure them in /etc/network/interfaces

auto lo
iface lo inet loopback

iface eth0 inet manual

auto br0
iface br0 inet dhcp
bridge_ports eth0

I also tried to configure them via virt-manager and I also tried to use macvtap.

In all three cases I was not able to establish a connection via untangle. Is there anything I am missing/doing wrong?

share|improve this question

if iptables is active, we can give the following rules.

sysctl -w net.ipv4.ip_forward=1
iptables -A FORWARD -m physdev --physdev-out br0 -j ACCEPT
iptables -A FORWARD -m physdev --physdev-in br0 -j ACCEPT
share|improve this answer

# The loopback network interface
auto lo
iface lo inet loopback

# The bribge network interface
auto br0
iface br0 inet dhcp
        bridge_ports eth0
        bridge_stp off
        bridge_fd 0
        bridge_maxwait 0

share|improve this answer
Your extra options bridge_stp, _fd, _maxwait aren't mentioned in the interfaces(5) manpage. Where did you find out what they do? – JigglyNaga 8 hours ago
This is an example where only one bridge is used and not needed stp – Andrey Golub 8 hours ago

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