After installing the operating system on each node for the architecture that you choose to deploy, you must configure the network interfaces. We recommend that you disable any automated network management tools and manually edit the appropriate configuration files for your distribution. For more information on how to configure networking on your distribution, see the documentation. documentation. documentation. SLES 12 or openSUSE documentation. All nodes require Internet access for administrative purposes such as package installation, security updates, DNS, and NTP. In most cases, nodes should obtain Internet access through the management network interface. To highlight the importance of network separation, the example architectures use private address space for the management network and assume that network infrastructure provides Internet access via NAT. To illustrate the flexibility of IaaS, the example architectures use public IP address space for the external network and assume that network infrastructure provides direct Internet access to instances in your OpenStack environment. In environments with only one block of public IP address space, both the management and external networks must ultimately obtain Internet access using it. For simplicity, the diagrams in this guide only show Internet access for OpenStack services. Use the YaST network module: # yast2 network For more information, see the SLES or the openSUSE documentation. Your distribution enables a restrictive firewall by default. During the installation process, certain steps will fail unless you alter or disable the firewall. For more information about securing your environment, refer to the OpenStack Security Guide. Your distribution does not enable a restrictive firewall by default. For more information about securing your environment, refer to the OpenStack Security Guide. Proceed to network configuration for the example OpenStack Networking (neutron) or legacy networking (nova-network) architecture.