The following series of events take place when an IP address is allocated to the VM.

1. The VM requests an IP address by sending the DHCP request packet.
2. The request reaches the firewall bridge, which has iptable configuration. The iptables rules must allow the packet to reach the integration bridge.
3. The integration bridge will tag the packet with the local VLAN ID and forward it to the tunnel bridge.
4. The tunnel bridge will translate the VLAN ID into segmentation ID and the packet will be sent out of the NOVA Compute host to the Neutron host.
5. The tunnel bridge on the Neutron host will receive the packet and de-encapsulate it and forward it to the integration bridge.
6. The integration bridge will forward the packet to the DHCP namespace.
7. The dnsmasq in the DHCP namespace will reply with a DHCP offer message having the IP address.

Let's now look at common issues faced by OpenStack administrators.