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<div>On Mar 18, 2014, at 7:40 AM, Roman Verchikov <<a href="mailto:rverchikov@mirantis.com">rverchikov@mirantis.com</a>> wrote:</div>
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Hi stakers,
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<div>We’re trying to replace dnsmasq-supplied DHCP for tenant VMs with a vendor’s baremetal DHCP server. In order to pass DHCP request to a vendor’s server and send DHCP response back to VM we decided to add another OVS bridge (we called it br-dhcp), connected
to integration bridge (br-int), which will have OVS rules connecting VM’s MAC address with br-dhcp port. In this scenario DHCP response will only find it’s way back to a VM if VM has globally-unique MAC address. </div>
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<div>My questions are: </div>
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<li>is having code which generates globally-unique MACs for VMs acceptable by the community at all?</li></ul>
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<div>This question tends to pop up from time to time and there are valid deployment and usage scenarios where you would want to assign the same MAC to multiple ports. </div>
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<li>is there a better solution to the problem (we also tried using dnsmasq as a DHCP relay there)?</li></ul>
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<div>That answer really depends on a number of factors.</div>
<div> - Are the IP allocations being handled inside or outside of Neutron?</div>
<div> - Do you allow different networks to have overlapping IP ranges?</div>
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<div>If it is outside of the OpenStack deployment then your code can use flow mods with you br-dhcp. If Neutron is managing the allocations or you allow overlapping IPs, you probably want to consider implementing a driver for the DHCP server.</div>
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<div>mark</div>
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