[Users] OpenVZ and IPv6

[Kevin Holly [Fusl]]

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Hi,

On 06/18/2015 11:13 PM, Todd Mueller wrote:
> [...]

I'm not entirely sure if you understand what he asks for.

When you do "vzctl set CTID --ipadd 2001:1234:1234:1234/64 --save", OpenVZ creates a route only for the network address (2001:1234:1234:1234::), but not for the entire /64 subnet which is unexpected behaviour already.

Inside the container, OpenVZ automatically adds the network address (2001:1234:1234:1234::) to venet0.

2001:1234:1234:1234:: is now reachable from the outside

If you add 2001:1234:1234:1234::1 as an address inside the container, it should send a NDP packet to update neighbours about the new IPv6 address (including the router) but what we see instead is 2001:1234:1234:1234::1 staying unreachable.

OpenVZ in this case treats the 2001:1234:1234:1234::/64 subnet as a single address (which is 2001:1234:1234:1234::) instead of the subnet we requested and throws away all subnet information.


How we expect it to work instead:

"vzctl set CTID --ipadd 2001:1234:1234:1234::/64 --save" should add an entire /64 route and allow the container to use the entire /64 subnet as outgoing IPv6 address

vzctl should not by default add an IPv6 address from this subnet OR add 2001:1234:1234:1234:: by default to the container.

Inside the container we should now be able to add 2001:1234:1234:1234::1 as another IPv6 address to venet0 and OpenVZ kernel/the hardware node should forward NDP packets for updating neighbours including routers with the new IPv6 address.

The addresses 2001:1234:1234:1234:: and 2001:1234:1234:1234::1 should now be reachable from outside.


I hope that I explained this enough in detail so everyone reading should get an idea of what we mean.

- -- 
Best regards

Kevin Holly - root at hallowe.lt - http://hallowe.lt/
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