Devstack networking/can't ping instances

Question

I am facing a problem how to set up network correctly while using ubuntu 17.10 in virtualbox. I have problem with pinging my instances from host PC and even from guest VM. Same problem in instances, they can't ping VMs or host pc. In virtualbox I am using 3 network adapters (NAT for internet access, 2x host only network paravirtualized [one for communication between nodes another one was meant to be public interface for instances]).

/etc/network/interfaces

# The loopback network interface
auto lo
iface lo inet loopback

# VirtualBox NAT -- for Internet access to VM
auto enp0s3
iface enp0s3 inet dhcp

auto enp0s8
iface enp0s8 inet static
      address 172.18.161.6
      netmask 255.255.255.0

auto enp0s9
iface enp0s9 inet manual
        up ip link set dev $iface up
        down ip link set dev $iface down

And devstack local.conf was from this page (tried all of them): https://docs.openstack.org/devstack/latest/guides/neutron.html

Answer 1

I don't know what your configuration files looks like, but for sure, I can suggest for these kinda issues, try to debug step by step.

1: From instance, ping default GW, ie virtual router connecting internal network with the external network. If success, go to step 2. If fail, you got your culprit.

2: from the virtual router, ping host endpoint. If successful, try the other way round. If fail, you got your culprit.

If everything works fine, check configuration files, default gw, routing rules etc ...

Do let me, if it works or not !!

Answer 2

After to successfully install Devstack, if you want to grant access from and to instances, you need configure a bunch of settings:

1. In Security Groups add ingress rules to ICMP, SSH, HTTP, HTTPS, etc;
2. In the private Network, edit private-subnet to add a DNS Name Servers (8.8.8.8, 1.1.1.1, etc);
3. Allocated some Floating IP's;
4. Launch some instances;
5. Associate a floating IP to each instance;
6. Set the proxy_arp and iptables (in the host Devstack).

Try to follow this: How to expose the Devstack floating ip to the external world?