On 01/17/2012 02:57 PM, Jorge Fábregas wrote:
> Hello everyone,
>
> I'm learning about bridged networking and how it is applied to virtual
> environments (bypassing all the automation provided by libvirtd etc) .
> I have a question regarding ip configuration for the virtual bridge.
>
> Let's say I have a host (my machine) where I want to run 3 VMs bridged
> to my home network (thru eth0). I have a DHCP server running on my DSL
> router, and I have dhcp enabled on my 3 VMs so they all should get a
> lease from the DHCP.
>
> As far as a I know these are the raw steps needed to accomplish this:
>
> 1- create br0
> 2- remove current ip address from eth0
> 3- enslave eth0 to br0
> 4- create tap devices
> 5- attach tap devices to br0
> 6- assign tap devices to every VM
>
> As you can see I haven't assigned an ip address to the virtual bridge
> (br0). Why is it that (on almost any site that I visit with this setup)
> they always end up assigning an ip address to br0?
>
> Thanks in advance!
> Jorge
> _______________________________________________
> virt mailing list
> virt@lists.fedoraproject.org
> https://admin.fedoraproject.org/mailman/listinfo/virt
There should be no reason to use tap devices as the bridge device can be
assigned as a network controller like so:
<interface type='bridge'>
<mac address='52:54:00:22:92:24'/>
<source bridge='br0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03'
function='0x0'/>
</interface>
<interface type='bridge'>
<mac address='52:54:00:7c:0c:db'/>
<source bridge='br1'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06'
function='0x0'/>
</interface>
Using virtmanager to create the network interface would add the above tags and
attributes to the guest's config file by creating a Bridge type interface.
Assign the host's IP addresses to the brX devices:
br0 Link encap:Ethernet HWaddr BC:AE:C5:BE:07:DD
inet addr:ww.xxx.yyy.zz Bcast:ww.xxx.yyy.yy Mask:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:28384 errors:0 dropped:0 overruns:0 frame:0
TX packets:16265 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:34899139 (33.2 MiB) TX bytes:2018000 (1.9 MiB)
It would look like eth0 on the guest.
And the guest IP address to ethX:
eth0 Link encap:Ethernet HWaddr 52:54:00:1B:A4:E6
inet addr:ww.xxx.yyy.xz Bcast:ww.xxx.yyy.yy Mask:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3291 errors:0 dropped:0 overruns:0 frame:0
TX packets:2140 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:995099 (971.7 KiB) TX bytes:414119 (404.4 KiB)
Interrupt:11
On the host ifcfg-br0:
DEVICE="br0"
TYPE="Bridge"
BOOTPROTO="none"
ONBOOT="yes"
DELAY=0
GATEWAY="ww.xxx.yyy.zz"
IPADDR="ww.xxx.yyy.zx"
NETMASK="255.255.255.240"
IPV6INIT=no
On the host ifcfg-eth0:
DEVICE="eth0"
HWADDR="00:00:00:00:00:00"
ONBOOT="yes"
BRIDGE="br0"
IPV6INIT=no
On the guest ifcfg-eth0:
DEVICE="eth0"
BOOTPROTO="none"
HWADDR="52:54:00:22:92:24"
ONBOOT="yes"
IPADDR="ww.xxx.yyy.xz"
NETMASK="255.255.255.240"
GATEWAY="ww.xxx.yyy.zx"
DNS1="ww.xxx.yyy.xx"
Emmett
_______________________________________________
virt mailing list
virt@lists.fedoraproject.org
https://admin.fedoraproject.org/mailman/listinfo/virt
