During the fabric registration process, an ACI node usually transitions across different states. These states are usually recorded in the Fabric Node Vector (FNV) table, which can be checked using the below command on the APIC acidiag fnvread States and descriptions: Unknown – Node has been discovered but no Node ID policy has been configured Undiscovered – Node ID has been configured but the node is yet to be discovered Discovering – Node has been discovered but VTEP IP has not yet been assigned Unsupported – Node is not a supported model Disabled – Node has been decommissioned Inactive – There is no IP connectivity Active – Node is active