Free Implementing Cisco Enterprise Advanced Routing and Services Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Implementing Cisco Enterprise Advanced Routing and Services practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A Cisco router learns the same destination prefix from OSPF and internal EIGRP. Both next hops are reachable. Which route is installed by default?

   1. A. The OSPF route because OSPF has the higher default administrative distance
   2. B. The internal EIGRP route because its default administrative distance is lower
   3. C. The route with the lower protocol metric, even across these different protocols
   4. D. Both routes because they describe the same prefix from separate protocols

   Answer: B

   Explanation: Cisco states, "the router prefers the EIGRP route by default because internal EIGRP has an administrative distance of 90, while OSPF has an administrative distance of 110." For the same prefix, EIGRP's lower AD wins the RIB comparison.

   Reference: Understand Administrative Distance — Additional Uses of AD, EIGRP/OSPF example

2. 2What information does LDP exchange between MPLS label switch routers to support hop-by-hop forwarding?

   1. A. Bindings between labels and prefixes
   2. B. BGP local preference values
   3. C. OSPF area membership records
   4. D. EIGRP reported-distance values

   Answer: A

   Explanation: Cisco says LDP lets LSRs "request, distribute, and release label prefix binding information to peer devices in a network." These bindings map routing destinations to labels.

   Reference: MPLS Configuration Guide, Cisco IOS XE 17.x - MPLS Label Distribution Protocol — Introduction to MPLS Label Distribution Protocol

3. 3An IOS XE login method list is `group radius local`. The RADIUS server does not respond. What happens next?

   1. A. The router attempts authentication against its local username database
   2. B. The router denies access immediately without trying the local method
   3. C. The router accepts the login without checking a second method
   4. D. The router changes the method list to TACACS+ automatically

   Answer: A

   Explanation: Cisco states, "If that method fails to respond, the Cisco IOS XE software selects the next authentication method listed in the method list." Because `local` is next, the router tries its username database.

   Reference: Security and VPN Configuration Guide, Cisco IOS XE 17.x - Configuring Authentication — Named Method Lists for Authentication

4. 4Remote CLI sessions to a Cisco router must be encrypted. Which management protocol meets that requirement?

   1. A. Telnet
   2. B. TFTP
   3. C. SSH
   4. D. HTTP

   Answer: C

   Explanation: Cisco says "SSH provides more security for remote connections than Telnet does by providing strong encryption when a device is authenticated." SSH therefore meets the encrypted CLI requirement.

   Reference: Cisco Catalyst IR8340 Router Software Configuration Guide - Configuring Secure Shell — Configuring Secure Shell, SSH And Router Access

5. 5A candidate route has a better administrative distance than a competing route, but its next hop cannot be resolved. What prevents it from appearing in the routing table?

   1. A. The route's better administrative distance is ignored until its next hop is reachable
   2. B. The competing protocol's metric replaces the unresolved next hop address
   3. C. The router installs the route but suppresses it from forwarding only
   4. D. The route is installed automatically because administrative distance is lower

   Answer: A

   Explanation: Cisco states, "If the next hop cannot be resolved, the route is not installed in the routing table." A favorable AD cannot bypass next-hop validation.

   Reference: Understand Administrative Distance — Select the Best Path > Route Installation

6. 6An IOS XE device has IP routing but cannot label-switch packets. Which forwarding prerequisite should an engineer check?

   1. A. Cisco Express Forwarding is enabled
   2. B. BGP route reflection is enabled
   3. C. OSPF virtual links are enabled
   4. D. Policy-based routing is enabled

   Answer: A

   Explanation: Cisco states, "Label switching on a device requires that Cisco Express Forwarding be enabled on that device." CEF is the specific prerequisite.

   Reference: MPLS Configuration Guide, Cisco IOS XE 17.x - MPLS Label Distribution Protocol — Prerequisites for MPLS Label Distribution Protocol

7. 7The RADIUS server explicitly rejects a login under IOS XE method list `group radius local`. Will the router try the local database for that same login?

   1. A. No; an authentication FAIL stops method-list evaluation
   2. B. Yes; every rejection triggers the local backup method
   3. C. Yes; but only after the RADIUS server times out
   4. D. No; because local databases are unavailable with RADIUS

   Answer: A

   Explanation: Cisco says, "If authentication fails at any point in this cycle--meaning that the security server or local username database responds by denying the user access--the authentication process stops and no other authentication methods are attempted." A rejection differs from a server error.

   Reference: Security and VPN Configuration Guide, Cisco IOS XE 17.x - Configuring Authentication — Named Method Lists for Authentication, FAIL behavior

8. 8A router accepts Telnet sessions on its VTY lines even though SSH is available. Which VTY setting restricts inbound sessions to SSH?

   1. A. transport input telnet
   2. B. transport output ssh
   3. C. login local
   4. D. transport input ssh

   Answer: D

   Explanation: Under line vty, the guide shows "transport input ssh" and states it prevents non-SSH Telnet connections. The input transport controls inbound VTY protocols.

   Reference: Cisco Catalyst IR8340 Router Software Configuration Guide - Configuring Secure Shell — Configuring the SSH Server, VTY transport step

9. 9While interpreting `show ip route`, an engineer sees `[90/1]` next to a learned route. What do the two values represent?

   1. A. Administrative distance 90 and protocol metric 1
   2. B. Protocol metric 90 and administrative distance 1
   3. C. Route age 90 seconds and protocol metric 1
   4. D. Administrative distance 90 and prefix length 1

   Answer: A

   Explanation: Cisco says, "In show ip route output, the values in brackets use the format [administrative distance/metric]." Thus the first number is AD and the second is the metric.

   Reference: Understand Administrative Distance — Additional Uses of AD, show ip route format

10. 10At an MPLS transit router, which packet field is used to make the next forwarding lookup?

    1. A. The incoming MPLS label
    2. B. The source IP address
    3. C. The BGP local preference
    4. D. The OSPF area ID

    Answer: A

    Explanation: Cisco states that in MPLS forwarding, "the device looks at the incoming label, looks up the label in a table, and then forwards the packet to the next hop." The label drives this transit lookup.

    Reference: MPLS Configuration Guide, Cisco IOS XE 17.x - MPLS Label Distribution Protocol — Introduction to MPLS Label Distribution Protocol, forwarding comparison