Routing Protocols & IP Addressing Flashcards

An ArubaOS-CX switch has two equal-cost paths to a destination in its routing table. What behavior does the switch exhibit by default?

Answer: It uses ECMP to load-balance across both paths

ArubaOS-CX supports Equal-Cost Multi-Path (ECMP) routing, distributing traffic across multiple equal-cost paths by default.

Which BGP attribute is used first when selecting the best path among multiple routes to the same prefix?

Answer: Weight

Cisco and Aruba implementations evaluate Weight first in BGP best-path selection; it is locally significant and not advertised to peers.

A host is assigned the IP address 192.168.10.50/27. What is the broadcast address of this subnet?

Answer: 192.168.10.63

A /27 subnet has 32 addresses; the block starting at 192.168.10.32 ends with broadcast 192.168.10.63.

On an ArubaOS-CX switch, what is the purpose of the 'ip helper-address' command on a VLAN interface?

Answer: It forwards DHCP broadcast requests to a unicast DHCP server

The 'ip helper-address' command configures DHCP relay, converting client broadcast requests to unicast packets forwarded to the specified server.

Which routing protocol uses the Diffusing Update Algorithm (DUAL) to guarantee loop-free paths?

Answer: EIGRP

EIGRP uses the DUAL algorithm to compute loop-free paths and identify feasible successors for fast convergence.

An ArubaOS-CX switch needs to redistribute connected routes into OSPF. Which configuration element is required?

Answer: The 'redistribute connected' command under the OSPF process

The 'redistribute connected' command under the OSPF router configuration redistributes directly connected routes into OSPF as external routes.

What is the function of a BGP route reflector in an iBGP topology?

Answer: It allows iBGP routes to be re-advertised to other iBGP peers without full mesh

A BGP route reflector eliminates the full-mesh iBGP requirement by re-advertising received iBGP routes to its clients.