After completing a VMware Cloud Director Availability appliance deployment, as a system administrator you can modify the network settings of the appliance by using the management interface.

Host Name Configuration

During the OVF deployment, as a system administrator, you can manually provide the appliance host name. If you skip this step, the DHCP server provides the host name. Some DHCP servers are not configured to provide a host name or do not support host name provisioning. In such cases, the appliance attempts to find the host name and performs a reverse DNS lookup by using the first non-link-local IP address of the default ens160 Ethernet adapter. If the request is successful, the appliance uses the provided domain name as a host name and ignores future host names received over DHCP. If the request is not successful, the appliance uses photon-machine as a host name.

After the deployment completes, you can modify the host name of the appliance by using the appliance management interface. Configuring a new host name overwrites the host name that is provided by DHCP.

DNS Settings Configuration

As a system administrator, you can configure the provisioning of DNS servers and Domain Search Path in manual or automatic mode.
Manual
As a system administrator, you must provide the static DNS settings.
Automatic
The DHCP server or Stateless Address Autoconfiguration (SLAAC) provides the DNS settings.

During the OVF deployment, you can manually provide the DNS settings. If you skip this step, the appliance uses the DNS settings provided by the DHCP server.

After the deployment completes, you can modify the DNS settings of the appliance by using the appliance management interface. When you provide the static DNS settings manually, all network adapters are configured to ignore the DNS settings that are provided by DHCP or SLAAC. Alternatively, you can switch to automatic mode by configuring one or more network adapters to use DHCP or SLAAC. Switching from manual to automatic mode overwrites all static DNS settings.

Network Adapter Configuration

During the OVF deployment, as a system administrator, you can provide the network adapter settings. If you do not populate the IP address, the adapter uses DHCPv4. After the deployment completes, you can change the adapter settings provided during deployment.

You can configure the network adapters in VMware Cloud Director Availability to use either IPv4 or IPv6 modes. You can provide the adapter settings manually or alternatively the settings can be received by using one of the following automatic mechanisms.

Manual
The manual adapter configuration requires you to provide a valid Classless Inter-Domain Routing (CIDR) static address. Enter the CIDR address as an IP address, followed by a forward slash and a network mask or a prefix length. You can also set a default gateway, that must be in the same network as the provided IP address. If a second adapter is configured manually with the same IP mode, skip setting the default gateway. You can also configure the maximum transmission unit (MTU), and if omitted, the appliance uses an MTU of 1500 bytes. You can set the static address, gateway, and MTU adapter settings for both IPv4 and IPv6 modes.
Automatic
DHCPv4, DHCPv6, or SLAAC can provide the automatic adapter configuration, depending on the IP mode.
By using DHCPv4 or DHCPv6, the network adapter is configured to:
  • Use the DNS servers that are provided by the DHCP server.
  • Use the search domains that are provided by the DHCP server.
  • Ignore all routes that are provided by the DHCPv4 server, if the appliance has a default gateway configured.
  • Remove all manually configured DNS settings such as DNS servers and search domains.
  • Remove custom MTU settings.
By using SLAACv6, the network adapter is configured to:
  • Enable IPv6 link-local addressing.
  • Accept IPv6 Router Advertisement (RA).
  • Accept DNS servers and search domains through RA.
  • Remove all manually configured DNS settings such as DNS servers and search domains.
  • Remove custom MTU settings.

Additional notes for the network adapter configuration:

  • If there are multiple sources of DNS settings, for example two NICs that use two different DHCP servers, the DNS requests are sent to all DHCP servers. The appliance uses the first one that responds. To avoid potential issues, you must ensure that there are no conflicting settings. As a best practice, avoid such a configuration.
  • To remove the configuration of the network adapter, you must click Unconfigure next to the IP mode. This action turns off the adapter and deletes all its settings, including static routes. Later, you can configure the adapter again, which turns it back on. Use this cleanup procedure, in case there are configuration leftovers that are causing unexpected network behavior.
  • To change the manually configured default gateway, you must first remove the configuration of the network adapter that is configured with it.
  • The upgrade to VMware Cloud Director Availability 4.0 attempts to migrate the network configuration of the old eth0 adapter. If using both IP modes before the upgrade, after the upgrade only one of them is enabled. Also, the upgrade replaces the eth0 adapter with the ens160 adapter.

Static Routes Configuration

VMware Cloud Director Availability 4.0 allows you as a system administrator to configure static routes that control how the network packets are sent to the destination.

In a typical environment, there is a default gateway that dynamically routes all the traffic to and from the external networks. Sometimes, you might want to route the traffic through another gateway. For example, you can use static routes when there is no dynamic route to the destination IP address, or when you want to override the dynamically learned route. To address such network setup, you can configure one or more static routes.

Note: Applying any network changes can lead to temporary network outages. For example, the browser connectivity to the management interface is interrupted when being accessed through the network adapter that was just reconfigured.