An overview of the complete DHCP configuration process is outlined in the following diagram, illustrating the main steps for preparing a NIOS appliance for use. Note that the process for configuring the DHCP server is the same for IPv4 and IPv6 networks, except that failover associations are not supported in IPv6 networks.

Configuring the Connecting Switch

To ensure that VRRP (Virtual Router Redundancy Protocol) works properly, configure the following settings at the port level for all the connecting switch ports (HA, LAN1, and LAN2):

• Spanning Tree Protocol: Disable. For vendor specific information, search for "HA" in the Infoblox Knowledge Base system at https://support.infoblox.com.
• Trunking: Disable
• EtherChannel: Disable
• IGMP Snooping: Disable
• DHCP Snooping: Disable or Enable Trust Interface

Note: You must disable DHCP Snooping to successfully run DHCP services on the Grid. For more information about DHCP services, see Configuring Infoblox DHCP Services.

• Port Channeling: Disable
• Speed and Duplex settings: Match these settings on both the Infoblox appliance and switch
• Disable other dynamic and proprietary protocols that might interrupt the forwarding of packets

Note: By default, a NIOS appliance automatically negotiates the optimal connection speed and transmission type (full or half duplex) on the physical links between its LAN1 or LAN1 (VLAN), HA, and MGMT ports and the Ethernet ports on the connecting switch. If the two appliances fail to auto-negotiate the optimal settings, see Modifying Ethernet Port Settings for steps you can take to resolve the problem.