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Zun changes public network interface configuration on compute node

Hi there,

I had installed openstack tools, keystone, neutron and zun on a controller and a compute machines using Stein release. Everything works fine until I try to launch a container on the compute node, where once the image is pulled something happens to the provider network interface (I'll show in details soon).

First of all this is how I'm creating the network and the subnet to use for the creation of the container:

$ openstack network create --share --provider-physical-network provider \
--provider-network-type flat provider1

$ openstack subnet create --subnet-range 203.0.113.0/24 --gateway 203.0.113.1 \
--network provider1 --allocation-pool start=203.0.113.11,end=203.0.113.250 \
--dns-nameserver 8.8.4.4 provider1-v4 --no-dhcp

I used the --no-dhcp option because otherwise I had problems also on the controller node with the provider interface.

On the compute node this is the output for ifconfig and ip route get on google dns ip:

ubuntu@compute1:~$ ifconfig
docker0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
      inet 172.17.0.1  netmask 255.255.0.0  broadcast 172.17.255.255
      ether 02:42:99:c2:be:3c  txqueuelen 0  (Ethernet)
      RX packets 0  bytes 0 (0.0 B)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 0  bytes 0 (0.0 B)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1400
      inet 192.168.1.24  netmask 255.255.0.0  broadcast 192.168.255.255
      inet6 fe80::f816:3eff:fe5e:e3b9  prefixlen 64  scopeid 0x20<link>
      ether fa:16:3e:5e:e3:b9  txqueuelen 1000  (Ethernet)
      RX packets 87436  bytes 3738200 (3.7 MB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 1074  bytes 152405 (152.4 KB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ens8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1458
      inet 10.0.0.4  netmask 255.0.0.0  broadcast 10.255.255.255
      inet6 fe80::f816:3eff:fe0d:ebb0  prefixlen 64  scopeid 0x20<link>
      ether fa:16:3e:0d:eb:b0  txqueuelen 1000  (Ethernet)
      RX packets 26519  bytes 14034097 (14.0 MB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 28846  bytes 9014451 (9.0 MB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
      inet 127.0.0.1  netmask 255.0.0.0
      inet6 ::1  prefixlen 128  scopeid 0x10<host>
      loop  txqueuelen 1000  (Local Loopback)
      RX packets 92  bytes 7076 (7.0 KB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 92  bytes 7076 (7.0 KB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ubuntu@compute1:~$ ip route get 8.8.8.8
8.8.8.8 via 192.168.0.1 dev ens3 src 192.168.1.24 uid 1000 
  cache

Where ens3 is the provider interface and ens8 is the management one.

Then I try to run a container:

openstack appcontainer run --name container --net network=$NET_ID cirros ping 8.8.8.8

Where $NET_ID is the ID of the net I've just created.

Now I lose my ssh connection with the compute node on the provider floating ip. When I get a new session using the managment interface from the controller node this is the output of the previous commands:

root@compute1:~# ifconfig
brqbe245ded-19: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1400
      inet 192.168.1.24  netmask 255.255.0.0  broadcast 192.168.255.255
      inet6 fe80::ecc7:91ff:feb9:92b7  prefixlen 64  scopeid 0x20<link>
      ether 9e:bd:31:15:e0:8b  txqueuelen 1000  (Ethernet)
      RX packets 369  bytes 12408 (12.4 KB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 67  bytes 6178 (6.1 KB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

 docker0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
      inet 172.17.0.1  netmask 255.255.0.0  broadcast 172.17.255.255
      ether 02:42:99:c2:be:3c  txqueuelen 0  (Ethernet)
      RX packets 0  bytes 0 (0.0 B)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 0  bytes 0 (0.0 B)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

 ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1400
      inet6 fe80::f816:3eff:fe5e:e3b9  prefixlen 64  scopeid 0x20<link>
      ether fa:16:3e:5e:e3:b9  txqueuelen 1000  (Ethernet)
      RX packets 88981  bytes 3855230 (3.8 MB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 1368  bytes 195602 (195.6 KB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

 ens8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1458
      inet 10.0.0.4  netmask 255.0.0.0  broadcast 10.255.255.255
      inet6 fe80::f816:3eff:fe0d:ebb0  prefixlen 64  scopeid 0x20<link>
      ether fa:16:3e:0d:eb:b0  txqueuelen 1000  (Ethernet)
      RX packets 27241  bytes 14400266 (14.4 MB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 29607  bytes 9228275 (9.2 MB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

 lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
      inet 127.0.0.1  netmask 255.0.0.0
      inet6 ::1  prefixlen 128  scopeid 0x10<host>
      loop  txqueuelen 1000  (Local Loopback)
      RX packets 332  bytes 26221 (26.2 KB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 332  bytes 26221 (26.2 KB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

 tap54451c58-e4: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
      inet6 fe80::9cbd:31ff:fe15:e08b  prefixlen 64  scopeid 0x20<link>
      ether 9e:bd:31:15:e0:8b  txqueuelen 1000  (Ethernet)
      RX packets 54  bytes 2532 (2.5 KB)
      RX errors 0  dropped 0  overruns 0  frame 0
      TX packets 327  bytes 14774 (14.7 KB)
      TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

root@compute1:~# ip route get 8.8.8.8
8.8.8.8 via 192.168.0.1 dev brqbe245ded-19 src 192.168.1.24 uid 0 
  cache

It seems like the subnet has been moved on another interface that is not capable to reach an internet connection.

Any idea of what could be the problem? I'd configured everything as described in the installation guide for Stein release. Let me know if you need additional or more specific informations.

Thank you in advance!