Facilitates IPv6 address auto-configuration, node discovery, and reachability maintenance within the ACI fabric. This protocol ensures efficient communication and network management across various Layer 3 interfaces.
The IPv6 Neighbor Discovery (ND) protocol is a network management mechanism that performs the following functions:
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Address auto-configuration of nodes and discovery of other nodes on the link.
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Determination of link-layer addresses, duplicate address detection, and finding available routers and DNS servers.
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Address prefix discovery and maintenance of reachability information for active neighbor nodes.
Neighbor Discovery Support and Configuration
The ACI fabric supports ND-specific Neighbor Solicitation or Neighbor Advertisement (NS or NA) and Router Solicitation or Router Advertisement (RS or RA) packet types on all Layer 3 interfaces. ACI bridge domain ND operates exclusively in flood mode.
The ACI fabric ND support includes the following components:
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Interface policies (
nd:IfPol) that control ND timers and behavior for NS/NA messages. -
ND prefix policies (
nd:PfxPol) that control RA messages. -
Configuration of IPv6 subnets for ND (fv:Subnet).
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ND interface policies for external networks.
Configuration options include the following:
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Adjacencies: Includes configurable static adjacencies and dynamic adjacencies learned via NS/NA packet exchange.
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Per Interface: Provides control of ND packets (NS/NA) such as Neighbor Solicitation Interval and Retry count, and control of RA packets including RA suppression and interval settings.
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Per Prefix: Controls parameters such as lifetime, preferred lifetime, and prefix configuration.
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Neighbor Discovery Duplicate Address Detection (DAD).