Dell EMC iDRAC Service Module Security Configuration Guide

SLAAC and/or DHCPv6 auto-configuration

When IPv4 address is unavailable on the OS-to-BMC Pass-through (USBNIC) host interface for communication with iDRAC, iSM attempts to use IPv6 protocol. If both v4 and v6 addresses are not available or iSM is unable to establish a successful TCP connection with iDRAC, then iSM switches to limited functionality mode where only a subset of features that are not dependent on the USBNIC interface are functional.