Hi, On czwartek, 7 kwietnia 2022 17:04:26 CEST A Monster wrote:

When I attach an interface to an external network, openstack gives an ip address of 192.168.10.13 to the instance, Inside the instance, I can see a new network interface, but it doesn't get an ip address automatically, and when I configure it to have 192.169.10.13 manually, I still cannot ping the other ips on this network, and I cannot ping 192.168.10.13 from the outside I think it's not feasible to attach instances to external networks.

External network in Neutron is the same L2 network as any other. The only difference is that such network is marked as "external" so neutron knows that can use floating Ips from it and use that network as router's gateway. Plugging instance into such network is totally valid and should works. Maybe Your external network have disabled dhcp and that's why VM don't get IP address automatically. Please check first if You configured proper netmask manually. Then please check step by step where Your packets are dropped. Maybe http://kaplonski.pl/blog/neutron-where-is-my-packet-2/[1] will be somehow helpful for You. This is mostly about vxlan (tenant) network but there is flat network used for router gateway there and traffic from your vm should go the same path as traffic from the router's gateway in that post. -- Slawek Kaplonski Principal Software Engineer Red Hat -------- [1] http://kaplonski.pl/blog/neutron-where-is-my-packet-2/