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Ok, I have a Proxmox 2.1 system with a Debian Squeeze base, and a FreeBSD KVM. I have a primary IP (obfuscated here) of 325.29.11.168 on a /27 subnet (though mine is the only IP I own on that subnet) and an additional subnet at 325.29.243.160/27 for my VM's.

I have followed the Proxmox guide to the letter, but while the VM's OS can ping the host, the host cannot ping the VM, nor is there any traffic from the broader internet to or from the VM. Obviously this is a routing issue of some kind, but I have looked all over the net for further examples and everyone seems to do it differently. Some people assign no IP to eth0 and only assign it to the bridge (which is the way I would expect) but that hasn't worked for me. Some people say to set bridge_ports to "eth0" and some say not to. The guide that my provider supplies for Proxmox says to do it like this, but so far I have had no success. Can anyone please tell me what I might be doing wrong ?

Contents of /etc/network/interfaces

auto lo
iface lo inet loopback

auto  eth0
iface eth0 inet static
  address   325.29.11.168
  broadcast 325.29.11.191
  pointtopoint 325.29.11.161
  gateway   325.29.11.161

auto vmbr0
iface vmbr0 inet static
    address 325.29.11.168
    broadcast 325.29.11.191
    bridge_ports none
    bridge_stp off
    bridge_fd 0
    up ip route add 325.29.243.160/27 dev vmbr0

Routing table:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
325.29.243.160 U     0      0        0 vmbr0
325.29.11.160 U     0      0        0 eth0
325.29.11.160 U     0      0        0 vmbr0         325.29.11.161         UG    0      0        0 eth0


bridge name     bridge id               STP enabled     interfaces
vmbr0           8000.0ee2dbb315e0       no              tap100i0
share|improve this question
Did you enable ipv4_forwarding in /sys? iptables in the way (iptables -L -n)? Also, if it's a routing issue, post the output of the "route -n" command of host and VM. Also output 'brtcl show'. Lastly, most VM setups are best served by having one bridge in which all VM's hang their virtual network interfaces and having them all on the same subnet. That way, it's like a virtual network switch where all you need to do is "plug in" the VM. Host and VM are in the same broadcast domain then. –  Halfgaar Jun 10 '12 at 6:02
Yes, ip forwarding is enabled. route and brctl information is found here: [link]pastebin.com/gEDr3Ezm[/link] –  Pawz Jun 10 '12 at 7:35
oh and iptables is open, with all tables being in ACCEPT as default –  Pawz Jun 10 '12 at 7:36
Pastebin link doesn't work; you can just edit in your original post. Edit: never mind; I did it for you; pending peer review. –  Halfgaar Jun 10 '12 at 8:06
What does traceroute/tracepath yield? Perhaps it gives some insight where the path stops. –  Halfgaar Jun 10 '12 at 11:41

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