Cisco Certified Support Technician (CCST) NetworkingIP ConnectivityHard

A network engineer is configuring an IPv6 static route on a Cisco router. The destination network is 2001:DB8:ACAD:1::/64, and the next-hop IPv6 address is 2001:DB8:ACAD:F::1. The exit interface is GigabitEthernet0/1. Which command correctly configures this route?

  1. Aipv6 route 2001:DB8:ACAD:1::/64 GigabitEthernet0/1 2001:DB8:ACAD:F::1
  2. Bipv6 route 2001:DB8:ACAD:1::/64 2001:DB8:ACAD:F::1
  3. Cip route 2001:DB8:ACAD:1::/64 2001:DB8:ACAD:F::1
  4. Dipv6 route 2001:DB8:ACAD:1::/64 GigabitEthernet0/1
Show answer & explanation

Correct answer: A. ipv6 route 2001:DB8:ACAD:1::/64 GigabitEthernet0/1 2001:DB8:ACAD:F::1

For an IPv6 static route using a next-hop IPv6 address, it is best practice, and often required for multi-access segments, to specify both the exit interface and the next-hop IPv6 address. This prevents potential issues with recursive lookups via link-local addresses.

Why the other options are wrong

  • B. This command specifies only the next-hop IP, which can cause issues on multi-access interfaces if the router doesn't resolve the next-hop to a link-local address.
  • C. The command 'ip route' is used for IPv4, not IPv6; the correct command for IPv6 is 'ipv6 route'.
  • D. This command specifies only the exit interface, which is typically used for point-to-point links or when the next-hop is a link-local address.

IPv6 Static Route Configuration

Configuring an IPv6 static route involves specifying the destination prefix, next-hop IPv6 address, and often the exit interface, especially on multi-access networks.

  • Command starts with `ipv6 route`.
  • Destination prefix includes the prefix length (e.g., /64).
  • For global unicast next-hops on multi-access links, specify both interface and next-hop IP.

Memory trick: Interface and Next-Hop Ensure Correct Route Resolution.

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