[Openstack-devel] [Xen-API] nova-xcp-network plugin searching for a xapi0 interface

[John Garbutt]

This sounds a lot like a configuration issue with your guest network bridge. Are you OK to supply your nova.conf file?

Also, have you tried using DevStack first? It is a good way to get the hang of how the flags work.

Thanks,
John

-----Original Message-----
From: Dave Scott 
Sent: 19 March 2012 10:04
To: 'Thomas Goirand'; xen-api; PKG OpenStack; openstack at lists.launchpad.net; John Garbutt
Subject: RE: [Xen-API] nova-xcp-network plugin searching for a xapi0 interface

Hi,

> When I start instances with Nova, using XCP on a Debian dom0, it seems 
> that the Nova XenAPI plugin needs to access to a xapi0 network 
> interface. If it's not their, the plugin just fails, and there's a 
> python stack dump.
> 
> So I have created a bridge called xapi0 on my dom0, and now I can 
> start instances. But then, I have no network connectivity to my VMs.
> 
> I wonder what this xapi0 network interface is for, and what is the 
> correct networking model to have connectivity to my instances. When 
> starting VMs, I don't see any network topology change in the dom0, or 
> in my Openstack domU, which I think isn't right. Is the "normal" setup 
> supposed to work with Quantum? Can it work without it?

I'm not familiar with the design of the Nova plugins but my guess is that they're trying to use the "Host internal management network" -- a network from which VMs can access the XenAPI (i.e. talk to xapi in domain 0).

On recent XCP versions the default bridge name changed to "xenapi" to make it easier to distinguish from a firewall rules PoV.

# xe network-list bridge=xenapi
uuid ( RO)                : 7e4b05a7-2135-a71f-f02e-7762ff56fa0d
          name-label ( RW): Host internal management network
    name-description ( RW): Network on which guests will be assigned a private link-local IP address which can be used to talk XenAPI
              bridge ( RO): xenapi

Note that the actual linux bridge (or openvswitch) is created on demand so you won't see it in "brctl show" or "ovs-vsctl show" until it's being used.

Try changing "xapi0" to "xenapi" in the plugins and see if they work better?

--
Dave Scott

> 
> Can someone from the XenServer team enlighten me with the necessary 
> knowledge? (The documentation about the necessary network setup is 
> very
> scarce: I didn't find anything!)
> 
> Cheers,
> 
> Thomas
> 
> P.S: Apart from that, it seems to work now with our Debian packages, 
> even though it seems *very* slow to start instances, and I still can't 
> get in the console of the VMs... :(
> 
> _______________________________________________
> xen-api mailing list
> xen-api at lists.xen.org
> http://lists.xen.org/cgi-bin/mailman/listinfo/xen-api