VMMs and networks

[Jerry Feldman]

On 04/01/2009 04:16 PM, Bill Bogstad wrote:
> 2009/4/1 Jerry Feldman <gaf-mNDKBlG2WHs at public.gmane.org>:
>  =20
>> ....
>>
>> example:
>> eth0 - host os ip address aaa.bbb.ccc.ddd - not used by VM
>> eth1 - host os (no IP configured) - VM connected as aaa.bbb.ccc.dde
>>    =20
>
> If you see this as two separate problems, it doesn't seem that hard to =
me.
>
> 1. Get host OS to not use eth1.  - This has nothing to do with VMs and
> is totally host OS dependent. On modern Linux systems, Network Manager
> has a tendency to bring up any interface which isn't statically
> configured somewhere so you need to 'statically' configure etj1.
> OTOH, you don't actually want the host OS to use eth1, but you do want
> the interface brought
> 'up' so the VM can use it.  On Ubuntu, something like:
>
>  auto eth1
>  iface eth1 inet manual
>       up ifconfig $IFACE 0.0.0.0 up
>       down ifconfig $IFACE down
>
> in the /etc/network/interfaces file will probably work.  The ifconfig
> with no IP address should bring up the interface without making it
> active for IP use by the host OS. It's been a while since I did
> Fedora/Redhat, but I'm guessing something could be
> put in /etc/sysconfig/network-scripts/ifcfg-eth1 to do something simila=
r.
>
> 2. Get the VM to bridge to the eth1 interface. - Use whatever method
> you would normally use to get the VM to use
> eth1.  The VM shouldn't care that the host OS isn't using the interface=
=2E
>  =20
Another thing I need to add to my presentation are ways to share data=20
between a VM and the host OS. The VMM can set up shared folders, but=20
additionally, the host could use NFS or Samba to export directories to=20
the VM, or the VM could use share its files with both the host OS, and=20
other systems on the subnet. In these cases, it does not matter what=20
file system (ext3, NTFS, ...) exists since the VMM will export them=20
properly to the guest os. I'm not sure how KVM/QEMU handle these, but=20
Samba works.

--=20
Jerry Feldman <gaf-mNDKBlG2WHs at public.gmane.org>
Boston Linux and Unix
PGP key id: 537C5846
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