Re: Can I use a native Linux installation as DomU?

[Brad Spencer <brad%anduin.eldar.org@localhost>]

   On Sun, Aug 24, 2014 at 10:41:09PM +0100, Gerard Lally wrote:
   > Perhaps Fedora already specifies mounts this way; Slackware doesn't.

   Yes, they already use UUID in Fedora.

   > I also found it easier to set up if I used LVM. Another thing you should
   > do while in bare-metal Fedora is set up SSH, VNC and/or XDMCP, so that
   > you will be able to log into Fedora when it's running as a domU.

   I am stuck on networking. My Dom0 uses wifi, which is bridged with
   bridge0.

   By setting static IP on DomU I was able to ssh/network with Dom0 but not
   able to connect with the internet. May be I have to do packet forwarding
   explicitly on Dom0. But that sounds a little roundabout.

   Perhaps my situation is same as described here:
   http://wiki.xen.org/wiki/Xen_in_WiFi_networks

   Will investigate.

   Mayuresh.



Yes, you are almost certainly running into that issue, as I did.  There
does not appear to exist, in NetBSD, anything like Linux ebtables, which
basically can do a sort of Layer 2 NAT using the MAC address.  Virtualbox,
apparently, does this too in its own way, when it detects that you are
bridging to a wireless interface.  The quick solution I ended up using was
to put NAT on the DOM0 hypervisor, and fix it all up at Layer 3.  You may
be aided in this by creating a private internal network for the guests
with their own IP address space.  You can use a tap device on the
hypervisor to get it to participate in that network, if you need it to.
You then simply turn on route forwarding and use ipnat.

I looked a bit at the userland bridge pkgsrc/net/bridged, which basically
is a BPF packet copier and thought about wedging a MAC rewritter inside of
it, but a lack of time on my part kept me from pursuing this any further.
I wasn't sure if the in kernel bridge code had access to everything
needed, like the frame headers, although the presence of IPF in the bridge
code might suggest that it does.  Just no time to look...

It would certainly be better for own selfish purposes if this could all
work at Layer 2 when NetBSD is a DOM0 maybe via ipf, or some such.

I use a Lenovo T530 running NetBSD 6.1.4 DOM0 with Xen 4.2.  Some of my
Xen guests could use the wireless card and some could use the hardwire
when they are both available, which would be handy for my purposes.




-- 
Brad Spencer - brad%anduin.eldar.org@localhost - KC8VKS
http://anduin.eldar.org  - & -  http://anduin.ipv6.eldar.org [IPv6 only]