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neuraltoxin

Member

Registered: 2016-09-10

Posts: 4

[SOLVED]: QEMU Cannot get Guest on Lan of Host with 2 NICs and VPN

Hello,
I've been working on this for a couple of days now. Have searched high and low and read the Wiki on QEMU several times. I have 2 nics:

Using netctl & dnsmasq

enp3s0 (static 10.0.0.1 LAN facing NIC)
emp032f6 (WAN - dhcp from my ISP)
tun0 (VPN to OpenVPN provider)
docker0 (for docker fun - not really relevant here)

I use firehol to do al the iptable rules. NAT, masquerading etc works great. I have a wireless router connected to enp3s0 so everything in my home network gets an address on the 10.0.0.x subnet and life is good.

I have Windows 10 all up and running using qemu and out of the box, the host OS is able to access the internet using qemu's NAT/DHCP - but nirvana would be getting the Windows 10 host to be just like another machine on my LAN network.

I've tried setting up a tap0 nic and used the Red Hat virtio drivers to get a nic up and running in the Win10 host however, it is unable to access my LAN or the internet. I've tried bridging tap0, enp3s0 together using br0 and all that managed to do take my lan down. I was sure to update the firehol rules:

interface tap0 win_tap
        policy accept
interface br0 win_br
        policy accept

I've tried;

-net nic,model=virtio,macaddr=52:54:DE:AD:BE:EF -net bridge,br=br0

and

#-net nic,model=virtio -net tap,ifname=tap0,script=no,downscript=no

and no joy.

I got this far without asking for help thanks for all who have posted and written an excellent wiki. Now, help would be appreciated:

Thanks,
NT

References:
https://wiki.archlinux.org/index.php/QEMU#Networking
http://www.linux-kvm.org/page/Networking
http://lifeisabug.com/kvm-virtualizatio … s-systemd/

Last edited by neuraltoxin (2016-09-11 16:08:55)

neuraltoxin

Member

Registered: 2016-09-10

Posts: 4

Re: [SOLVED]: QEMU Cannot get Guest on Lan of Host with 2 NICs and VPN

I've managed to solve the issue with the bridge. I was missing the ifup script where the tap0 interface is added to br0.

I now have a firewall issue however. Am not able to access the guest OS from the host (traceroute, ping, RDP). The guest OS firewall is disabled. Works when the host firewall is disabled however, I'm not able to pinpoint why enp3s0 -> tap0 traffic is getting dropped

neuraltoxin

Member

Registered: 2016-09-10

Posts: 4

Re: [SOLVED]: QEMU Cannot get Guest on Lan of Host with 2 NICs and VPN

Alright - not intuitive but I looked at the firehol logs and I needed the following:

router bridge2bridge inface br0 outface br0
        route all accept

Everything working well now.