Secure, reliable operation of VMware Cloud Director depends on a secure, reliable network that supports forward and reverse lookup of host names, a network time service, and other services. Your network must meet these requirements before you begin installing VMware Cloud Director.

The network that connects the VMware Cloud Director servers, the database server, the vCenter Server systems, and the NSX components, must meet several requirements:
IP addresses
Starting with VMware Cloud Director 10.4, the console proxy uses the same IP address and port as the REST API. The console proxy and REST API use a single certificate. Because of the unified access point, customizing the VMware Cloud Director public console proxy address is no longer necessary.
Note: VMware Cloud Director 10.4.1 and later do not support the legacy implementation of the console proxy feature.
Network Time Service

You must use a network time service such as NTP to synchronize the clocks of all VMware Cloud Director servers, including the database server. The maximum allowable drift between the clocks of synchronized servers is 2 seconds.

For the VMware Cloud Director appliance deployments, the NFS server used for the transfer share must use a network time service such as NTP to synchronize its clock with that of the VMware Cloud Director appliances. The maximum allowable drift between the clocks of synchronized servers is 2 seconds.

Server Time Zones
All VMware Cloud Director servers, including the NFS server used for the transfer share and the database server, must be configured to be in the same time zone.
Host Name Resolution
All host names that you specify during installation and configuration must be resolvable by DNS using forward and reverse lookup of the fully qualified domain name or the unqualified hostname. For example, for a host named vcloud.example.com, both of the following commands must succeed on a VMware Cloud Director host: 
nslookup vcloud
nslookup vcloud.example.com
In addition, if the host vcloud.example.com has the IP address 192.168.1.1, the following command must return vcloud.example.com: 
nslookup 192.168.1.1
Reverse DNS lookup of the eth0 IP address is required for the appliance. The following command must succeed in your environment: 
host -W 15 -R 1 -T <eth0-IP-address>

The hostnames of the VMware Cloud Director cells must not contain any underscores.

Note: In the initialization steps following the appliance deployment, if your DNS servers are not located in the local network, the appliance VM must connect to them through the default route over the eth0 IP address. If the VM attempts to reach a DNS server through the configured static routes, this results in an [ERROR] Hostname was not updated via dns reverse-lookup. Failing OS configuration phase. error. After the VM connects to a DNS server through the default route, you can change the DNS and route configurations of your VMware Cloud Director appliances.