Virtualization

A network engineer needs to run multiple isolated routing tables on a single Cisco IOS-XE router so that three separate customer networks can share the same physical hardware without any routing information overlapping. No overlay tunneling or MPLS is available. Which data-path virtualization technology should the engineer implement to achieve control-plane separation on the router?

A network engineer must connect two remote enterprise sites over a service-provider IP backbone that does not support the customer's dynamic routing protocol natively. The engineer needs a virtual point-to-point overlay that can carry OSPF adjacencies and multicast traffic between the sites' routers, but data confidentiality is being handled separately by an application-layer solution. Which device virtualization / data-path technology BEST meets these requirements with the least configuration overhead?

A network engineer configures a GRE tunnel between two branch routers. The tunnel source is set to a loopback interface, and the tunnel destination is the remote loopback. After configuration, the tunnel repeatedly flaps and the logs show '%TUN-5-RECURDOWN: Tunnel0 temporarily disabled due to recursive routing'. The engineer confirms both physical WAN links are up and the loopbacks are reachable via a dynamic routing protocol. What is the most likely cause of this issue?

A network engineer must connect two branch routers over the public Internet. The design requires that OSPF adjacencies and multicast video streams traverse the tunnel, while all traffic must also be encrypted for confidentiality. Which single tunnel technology, used alone, satisfies BOTH the multicast/routing-protocol requirement AND the encryption requirement?

A network architect is documenting the difference between LISP and VXLAN in an SD-Access fabric for a design review. A junior engineer asks which statement correctly describes the fundamental roles these two technologies play in the fabric architecture. Which statement is accurate?

A network engineer is bringing up a new Cisco Nexus 9000 switch. During initial setup, the engineer assigns the mgmt0 interface an IP address and later notices that all management traffic to the device's mgmt0 interface is fully isolated from the data-plane routing table, even though no explicit VRF configuration was entered. Which statement correctly explains this behavior?

A data center architect is comparing overlay encapsulation options for a new multitenant fabric. The team wants a Layer 2 overlay that transports tenant frames over a Layer 3 underlay, uses UDP as the transport protocol so that ECMP load balancing across the underlay can be achieved via source-port entropy, and provides a 24-bit segment identifier for tenant isolation. Which encapsulation technology meets ALL of these requirements?

A network engineer must keep the traffic of two customers, RED and BLUE, completely isolated across a single physical link between two routers, R1 and R2. Each router already has VRFs named RED and BLUE with the appropriate interfaces assigned. The engineer configures an 802.1Q trunk between R1 and R2 using subinterfaces. Which configuration step is required so that routing within each VRF is exchanged correctly across the link?

A network engineer has deployed VRF-lite on a Cisco IOS-XE router to separate GUEST and CORP traffic. Both VRFs must reach a shared DNS server located in a SHARED-SVCS VRF, but GUEST and CORP must remain isolated from each other. Using MP-BGP with route-target import/export on the router, which configuration approach correctly enables the shared services access while preserving isolation between GUEST and CORP?

A network engineer is deploying a VXLAN fabric in a data center to replace a legacy flood-and-learn design. The requirement is to minimize unnecessary BUM (broadcast, unknown unicast, multicast) traffic and to distribute host MAC and IP reachability information proactively between VTEPs. Which technology should the engineer configure to meet these requirements?

A data center engineer is deploying a VXLAN overlay across two leaf switches to extend Layer 2 connectivity without a BGP EVPN control plane. The design uses multicast for BUM (broadcast, unknown unicast, multicast) traffic replication. When a host behind Leaf-1 first sends an ARP request for a host behind Leaf-2, how do the VTEPs learn the remote host's MAC-to-VTEP mapping in this deployment?