4.2 GUA and LLA Static Configuration Flashcards
IPv6 GUAs are the same as public IPv4 addresses. They are globally unique and routable on the IPv6 internet. An IPv6 LLA lets two IPv6-enabled devices communicate with each other on the same link (subnet). It is easy to statically configure IPv6 GUAs and LLAs on routers to help you create an IPv6 network.
the command to configure an IPv6 GUA on an interface is ipv6 address ipv6-address/prefix-length.
Just as with IPv4, configuring static addresses on clients does not scale to larger environments. For this reason, most network administrators in an IPv6 network will enable dynamic assignment of IPv6 addresses.
There are two ways in which a device can obtain an IPv6 GUA automatically:
Stateless address autoconfiguration (SLAAC)
Stateful DHCPv6
Note: When DHCPv6 or SLAAC is used, the LLA of the router will automatically be specified as the default gateway address.
Configuring the LLA manually lets you create an address that is recognizable and easier to remember. Typically, it is only necessary to create recognizable LLAs on routers. This is beneficial because router LLAs are used as default gateway addresses and in routing advertisement messages.
LLAs can be configured manually using the ipv6 address ipv6-link-local-address link-local command. When an address begins with this hextet within the range of fe80 to febf, the link-local parameter must follow the address.
Statically configured LLAs are used to make them more easily recognizable as belonging to router R1.
Note: The exact same LLA could be configured on each link as long as it is unique on that link. This is because LLAs only have to be unique on that link. However, common practice is to create a different LLA on each interface of the router to make it easy to identify the router and the specific interface.
