I ran the below commands to create 2 instances in 2 different subnets

neutron net-create net1 neutron subnet-create net1 10.0.0.0/24 neutron net-create net2 neutron subnet-create net2 10.0.1.0/24 neutron router-create router1

neutron router-interface-add router1 SUBNET1_UUID neutron router-interface-add router1 SUBNET2_UUID

neutron port-create net1 --binding:profile type=dict vnic_type=hostdev neutron port-create net2 --binding:profile type=dict vnic_type=hostdev

nova boot --flavor 6 --image centos6.4_cloud-init centos6.4_1 --nic port-id=port1_UUID nova boot --flavor 6 --image centos6.4_cloud-init centos6.4_2 --nic port-id=port2_UUID

Both the instances are able to ping each other. Now, I ran the below commands to create floating IPs.

neutron net-create ext-net --shared --router:external=True

neutron subnet-create ext-net --name ext-subnet --allocation-pool start=10.227.78.124,end=10.227.78.125 --disable-dhcp --gateway 10.227.64.1 10.227.64.0/20

neutron router-gateway-set router1 ext-net

neutron floatingip-create ext-net

nova floating-ip-associate centos6.4_1 10.227.78.125

Now, the instances are not able to ping each other.

I am not able to ping floating IP assigned to instance.

The status of the router's internal interfaces is ACTIVE, but the status of External Gateway is DOWN.

How to fix this?