3

So I have a dedicated server from OVH. With that I got a /64 range of IPv6 addresses and 1 public IPv4 address. I purchased a second IPv4 address as a fallback.

The host is running the Xen hypervisor and I already set up the bridge 

bridge name bridge id STP enabled interfaces br0 8000.0cc47ac4292c no eno3 vif4.0 vif4.0-emu virbr0 8000.525400a2390a yes virbr0-nic

I was able to get the VM connected with both the IPv4 and IPv6 address (it will only be using IPv6 though) however as a test I changed the VM's MAC address from the one listed for my fallback and boom, no more IPv6 connectivity but once I set the MAC address back it was working right as rain.

Host ipv6 routing table

2607:5300:61:45b::/64 dev br0 proto kernel metric 256 pref medium 2607:5300:61:400::/56 dev eno3 proto kernel metric 202 mtu 1500 pref medium fe80::/64 dev eno3 proto kernel metric 256 pref medium fe80::/64 dev eno4 proto kernel metric 256 pref medium fe80::/64 dev br0 proto kernel metric 256 pref medium fe80::/64 dev vif4.0-emu proto kernel metric 256 pref medium fe80::/64 dev vif4.0 proto kernel metric 256 pref medium ff00::/8 dev eno3 metric 256 pref medium ff00::/8 dev eno4 metric 256 pref medium ff00::/8 dev br0 metric 256 pref medium ff00::/8 dev vif4.0-emu metric 256 pref medium ff00::/8 dev vif4.0 metric 256 pref medium default via fe80::205:73ff:fea0:0 dev br0 metric 1024 pref medium

Guest ipv6 routing table 

2607:5300:61:45b::/64 dev eth0 proto kernel metric 256 pref medium 2607:5300:61:400::/56 dev eth0 proto kernel metric 256 expires 2591946sec pref medium fe80::/64 dev eth0 proto kernel metric 256 pref medium default via fe80::205:73ff:fea0:0 dev eth0 proto ra metric 1024 expires 1746sec hoplimit 64 pref medium

Ideally what I'm looking to do is be able to create VM's that will have their own publicly routable IPv6 address without having to have a separate fallback IPv4 address for each one.

The host system is running Gentoo btw.

Improve this question
6
  • have you tried wiki.ubuntu.com/IPv6#Configure_your_Ubuntu_box_as_a_IPv6_router Commented Mar 3, 2017 at 12:39
  • I'm not sure what you are trying to accomplish with "I changed the VM's MAC address from the one listed for my fallback" You can use whatever unique MAC address you want in the guest. Could you show the change you made, in both host and guest interfaces? Commented Mar 3, 2017 at 13:24
  • 2
    You're on OVH, and their IPv6 support is limited, as you've discovered. VMs bridged directly to the physical network must use an OVH-assigned MAC address, but OVH won't assign such a MAC address except for a failover IPv4. But if you route to an internal virtual network, you don't have any IPv6 subnets to assign to it. Commented Mar 3, 2017 at 16:54
  • @MichaelHampton I'm actually going to try a cheat method. I have a /48 from Hurricane Electric so what I COULD do and still utilize the secondary IPv4 address is create a PFSense VM that's only function is to provide the /48 address range to my VM's. Commented Mar 3, 2017 at 17:53
  • @MichaelHampton, the annoying thing is that OVH appearently have assigned MAC-addresses to 3 machines 2-3 years ago, because it is working, but I can't make it work for new machines, not even a clone of a working machine. Commented Sep 26, 2018 at 11:21

1 Answer 1

Reset to default
0

I created my own solution where I created a PFSense firewall which will handle the natting of the single IPv4 address and allocate out globally routable IPv6 addresses. (Currently working on a separate issue with the setup but full IPv6 connectivity works just fine.)

To do the setup, create a separate bridge off the host machine (br1) and connect PFSense to both br0 and br1 WAN/LAN respectively. Have all your virtual machines bridge to br1 which will then receive a private IPv4 address and public IPv6 address from DHCP.

Improve this answer
1
  • I have done this, and it works for some hosts we did years ago, but I can't get it to work on new hosts. I believe everything is configured the same on both working and non-working. I must be forgetting a simple step to make it work. Commented Sep 24, 2018 at 11:28

You must log in to answer this question.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.