You must provide a set of external services before you deploy the components of this VMware Validated Design. External Services Overview in ROBOExternal services include Active Directory (AD), Dynamic Host Control Protocol (DHCP), Domain Name Services (DNS), Network Time Protocol (NTP), Simple Mail Transport Protocol (SMTP) Mail Relay, File Transfer Protocol (FTP), and Certificate Authority (CA). Physical Network Requirements in ROBOBefore you start deploying the ROBO SDDC, provide certain physical network configuration. VLANs, IP Subnets, and Application Virtual Networks in ROBOBefore you start deploying the ROBO SDDC, you must allocate VLANs and IP subnets to the different types of traffic in the ROBO, such as ESXi management, vSphere vMotion, and others. For application virtual networks, you must plan separate IP subnets for these networks. Host Names and IP Addresses in ROBOIn the SDDC, you must define the host names and IP addresses of the management components before the SDDC deployment. For some components, you must configure fully qualified domain names (FQDN) that map to their IP addresses on the DNS servers. Time Synchronization in ROBOSynchronized systems over NTP are essential for the validity of vCenter Single Sign-On and other certificates. Consistent system clocks are important for the proper operation of the components in the SDDC because in certain cases they rely on vCenter Single Sign-on. Active Directory Users and Groups in ROBOBefore you deploy and configure the SDDC in this VMware Validated Design, you must provide specific configuration of Active Directory users and groups. You use these users and groups for application login, for assigning roles in a tenant organization and for authentication in cross-application communication. Certificate Replacement in ROBOBefore you deploy the SDDC, you must configure a certificate authority and generate certificate files for the management products. According to this validated design, you replace the default VMCA- or self-signed certificates of the SDDC management products with certificates signed by a certificate authority (CA) during deployment. Datastore Requirements in ROBOFor certain features of the SDDC, such as back up and restore, log archiving, and content library, you must provide secondary storage.