Re: Xen3 + VLANs + multiple DOM0s cause loss of connectivity?

[Pavel Cahyna <pavel%netbsd.org@localhost>]

On Thu, Jan 24, 2008 at 12:26:52PM +0100, Johan Ihren wrote:
> Hi,
> 
> I have a complex Xen setup that utilizes VLANs to instantiate a virtual
> network topology on top of a physical infrastructure with several DOM0s
> connected through a single physical switch.
> 
> This has worked just fine with Xen2 for a long time. But now I've upgraded
> to Xen3 and unfortunately I've started having severe problems.
> 
> This doesn't seem to work:
> 
> * Two DOMUs running on separate DOM0s, communicating over IPv6 inside a VLAN.
>   I.e. a setup like the following doesn't work for me:
> 
>         domu1# ifconfig vlan0 create
>         domu1# ifconfig vlan0 vlan 10 vlanif xennet0
>         domu1# ifconfig vlan0 inet6 2001:1:1::1 prefixlen 32
>         domu2# ifconfig vlan0 create
>         domu2# ifconfig vlan0 vlan 10 vlanif xennet0
>         domu2# ifconfig vlan0 inet6 2001:1:1::2 prefixlen 32
>         domu2# ping6 2001:1:1::1                **** Doesn't work
> 
>   Note that if the DOMUs are on the *same* DOM0 then everything is ok.
> 
> * Two DOMUs running on separate DOM0s, communicating over IPv4 inside a VLAN
>   where at least one of the DOMUs is using *several* IP v4 addresses (i.e.
>   IP aliases) on the same interface.
> 
>         domu1# ifconfig vlan0 create
>         domu1# ifconfig vlan0 vlan 10 vlanif xennet0
>         domu1# ifconfig vlan0 inet 10.1.0.1/24
>         domu1# ifconfig vlan0 inet 10.1.0.2/24 alias
>         domu2# ifconfig vlan0 create
>         domu2# ifconfig vlan0 vlan 10 vlanif xennet0
>         domu2# ifconfig vlan0 inet 10.1.0.10/24
>         domu2# ping -n 10.1.0.1                 **** May work
>         domu2# ping -n 10.1.0.2                 **** Usually doesn't work

You should also show the configuration of network in the dom0s and the
type of their network cards.

Pavel