Dell MX9116n EMC SmartFabric OS10 User Guide Release 10.5.0 - Page 645

When an OS10 switch boots up, an IPv6 unicast link-local address automatically assigns to an interface using stateless configuration. A link-local address allows IPv6 devices on a local link to communicate without requiring a globally unique address. IPv6 reserves the address block FE80::/10 for link-local unicast addressing. Global addresses To enable stateless autoconfiguration of an IPv6 global address and set the interface to Host mode, use the ipv6 address autoconfig command. The router receives network prefixes in IPv6 router advertisements (RAs). An interface ID appends to the prefix. In Host mode, IPv6 forwarding is disabled. The no ipv6 address autoconfig command disables IPv6 global address autoconfiguration, and sets the interface to Router mode with IPv6 forwarding enabled. DHCP-assigned addresses As an alternative to stateless autoconfiguration, you can enable a network host to obtain IPv6 addresses using a DHCP server via stateful autoconfiguration using the ipv6 address dhcp command. A DHCPv6 server uses a prefix pool to configure a network address on an interface. The interface ID automatically generates. NOTE: On the management interfaces or management VLANs, when the IP address is acquired using DHCPv6, the IPv6 address with a /128 prefix-mask is assigned to the interface. However, to preserve backward compatibility and allow reachability, a static route with a /64 prefix-mask is also made available. Manally configured addresses An interface can have multiple IPv6 addresses. To configure an IPv6 address in addition to the link-local address, use the ipv6 address ipv6-address/mask command. Enter the full 128-bit IPv6 address, including the network prefix and a 64-bit interface ID. NOTE: Dell EMC Networking does not recommend configuring both a static IPv6 address and DHCPv6 on the same interface. You can also manually configure an IPv6 address by assigning: • A network prefix with the EUI-64 parameter using the ipv6 address ipv6-prefix eui64 command. A 64-bit interface ID automatically generates based on the MAC address. • A link-local address to use instead of the link-local address that automatically configures when you enable IPv6 using the ipv6 address link-local command. Configure IPv6 address OS10(config)# interface ethernet 1/1/8 OS10(conf-if-eth1/1/8)# ipv6 address 2001:dddd:0eee::4/64 Configure network prefix OS10(config)# interface ethernet 1/1/8 OS10(conf-if-eth1/1/8)# ipv6 address 2001:FF21:1:1::/64 eui64 Configure link-local address OS10(config)# interface ethernet 1/1/8 OS10(conf-if-eth1/1/8)# ipv6 address FE80::1/64 link-local Stateless autoconfiguration When an interface comes up, OS10 uses stateless autoconfiguration to generate a unique link-local IPv6 address with a FE80::/64 prefix and an interface ID generated from the MAC address. To use stateless autoconfiguration to assign a globally unique address using a prefix received in router advertisements, use the ipv6 address autoconfig command. Stateless autoconfiguration sets an interface in Host mode, and allows the interface connected to an IPv6 network to autoconfigure IPv6 addresses and communicate with other IPv6 devices on local links. A DHCP server is not required for automatic IPv6 interface configuration. IPv6 devices on a local link send router advertisement (RA) messages in response to solicitation messages received at startup. Perform stateless autoconfiguration of IPv6 addresses using: Prefix advertisement Routers use router advertisement messages to advertise the network prefix. Hosts append their interfaceidentifier MAC address to generate a valid IPv6 address. Layer 3 645