[ClusterLabs] Still Beginner STONITH Problem

[Klaus Wenninger]

On 7/17/20 3:56 PM, stefan.schmitz at farmpartner-tec.com wrote:
> Hello,
>
> I have now managed to get # fence_xvm -a 225.0.0.12 -o list to list at
> least its local Guest again. It seems the fence_virtd was not working
> properly anymore.
>
> Regarding the Network XML config
>
> # cat default.xml
>  <network>
>      <name>default</name>
>      <bridge name="virbr0"/>
>      <forward/>
>      <ip address="192.168.122.1" netmask="255.255.255.0">
>        <dhcp>
>          <range start="192.168.122.2" end="192.168.122.254"/>
>        </dhcp>
>      </ip>
>  </network>
>
> I have used "virsh net-edit default" to test other network Devices on
> the hosts but this did not change anything.
I have a similar networking setup with libvirt and it behaves
as expected - qemu tap devices are enslaved to that bridge.
But I have explicitly configured nat (<forward mode="nat"/>)
not relying on the default.
And instead of a DHCP-range I'm using fixed IP-assignment:

    <dhcp>
      <host mac='00:84:ED:70:01:02' name='node1' ip='192.168.123.2'/>
      <host mac='00:84:ED:70:01:03' name='node2' ip='192.168.123.3'/>
      <host mac='00:84:ED:70:01:04' name='node3' ip='192.168.123.4'/>
    </dhcp>

How does your VM part of the network-config look like.
I have something like:

    <interface type='bridge'>
      <mac address='00:84:ed:60:00:02'/>
      <source bridge='virbr0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03'
function='0x0'/>
    </interface>
>
> Regarding the statement
>
> > If it is created by libvirt - this is NAT and you will never
> > receive  output  from the other  host.
>
> I am at a loss an do not know why this is NAT. I am aware what NAT
> means, but what am I supposed to reconfigure here to dolve the problem?
As long as you stay within the subnet you are running on your bridge
you won't get natted but once it starts to route via the host the libvirt
default bridge will be natted.
What you can do is connect the bridges on your 2 hosts via layer 2.
Possible ways should be OpenVPN, knet, VLAN on your switches ...
(and yes - a cable ;-) )
If your guests are using DHCP you should probably configure
fixed IPs for those MACs.

Klaus
> Any help would be greatly appreciated.
> Thank you in advance.
>
> Kind regards
> Stefan Schmitz
>
>