provide ip to anopenstack vm via external dhcp

asked 2018-03-28 22:55:18 -0500

akarki gravatar image

Hi, I want to provide ip to a openstack vm via external dhcp running in my lab network. vm is also spwaned in flat lab network. Is it possible if so, how Any help would be appriciated.

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Just set up your DHCP server on that network, and ensure that no Neutron DHCP server is set up. For example, leave out DHCP configuration in and create subnets with openstack subnet create --no-dhcp.

Bernd Bausch gravatar imageBernd Bausch ( 2018-03-29 00:36:47 -0500 )edit

Hi, I have tried subnet with no-dhcp but only once did my vm received an ip..however i coud see the dhcpoffer in dhcp server i need to mahe changes in dhcp_agents_per_network option as well in neutron.conf

akarki gravatar imageakarki ( 2018-03-29 02:06:23 -0500 )edit

Not sure, but if you don't use the built-in DHCP servers, why not disable or uninstall them altogether?

Bernd Bausch gravatar imageBernd Bausch ( 2018-03-29 02:24:10 -0500 )edit

@Bernd Bausch: Does this apply to VLAN networks as well? we confiugred 1x Vlan network which is mapped to our OpenStack controller / compute nodes and we would like to manage the DHCP IP allocation from the external physical router. OpenStack creates an IP address pool too, which is not needed

fattony666 gravatar imagefattony666 ( 2018-09-05 03:42:29 -0500 )edit

I understand that you have a single VLAN to which all your cloud nodes are connected. IN this case they are not VLAN-aware, and the VLAN is just a network for them. Put a DHCP server on that same VLAN and it's not different from the above.

Bernd Bausch gravatar imageBernd Bausch ( 2018-09-05 05:43:21 -0500 )edit