300-410 Policy-Based Routing (PBR) Practice Test 4 — 15 Questions

Question 1

A network engineer runs the following command to troubleshoot a Policy-Based Routing (PBR) issue:

R1# show ip local policy
Interface   Route-map
local       PBR-LOCAL

What does this output indicate?

Accepted Answer

Local PBR is enabled for packets originated by the router.. The output shows that local PBR is configured using route-map PBR-LOCAL. This applies PBR to locally generated packets on the router.

Answer

PBR is applied to all incoming interfaces.

Answer

The route-map PBR-LOCAL is not configured.

Answer

PBR is applied to all outgoing interfaces.

Question 2

A network engineer runs the following command to troubleshoot a Policy-Based Routing (PBR) issue:

R1# show route-map PBR-MAP
route-map PBR-MAP, permit, sequence 10
  Match clauses:
    ip address (access-lists): 101
  Set clauses:
    ip next-hop 10.1.1.2
  Policy routing matches: 50 packets, 6000 bytes

What does this output indicate?

Accepted Answer

PBR is successfully forwarding matching traffic to 10.1.1.2.. The output shows that 50 packets have matched the route-map and have been policy-routed to next-hop 10.1.1.2. This indicates PBR is working.

Answer

The next-hop 10.1.1.2 is not reachable.

Answer

The ACL 101 is misconfigured.

Answer

PBR is not applied to any interface.

Question 3

A network engineer runs the following command to troubleshoot a Policy-Based Routing (PBR) issue:

R1# debug ip policy
Policy routing debugging is on
R1#
*Mar  1 00:15:30.789: IP: s=10.0.0.1 (FastEthernet0/0), d=20.0.0.1, len 100, policy match
*Mar  1 00:15:30.789: IP: s=10.0.0.1 (FastEthernet0/0), d=20.0.0.1, len 100, policy rejected
*Mar  1 00:15:30.789: IP: s=10.0.0.2 (FastEthernet0/0), d=20.0.0.2, len 100, policy match
*Mar  1 00:15:30.789: IP: s=10.0.0.2 (FastEthernet0/0), d=20.0.0.2, len 100, policy routed
*Mar  1 00:15:30.789: IP: FastEthernet0/0 to GigabitEthernet0/1 192.168.1.1

What does this output indicate?

Accepted Answer

The route-map has multiple sequences or ACL entries; one source is permitted, the other is denied or fails next-hop check.. The debug shows two packets: the first from 10.0.0.1 was rejected, while the second from 10.0.0.2 was successfully routed to 192.168.1.1. This suggests that the route-map may have multiple sequences or the ACL differentiates between the sources.

Answer

Both packets should have been rejected due to a misconfiguration.

Answer

The next-hop 192.168.1.1 is unreachable for the first packet.

Answer

The ACL is blocking all traffic from 10.0.0.1.

Question 4

A network engineer runs the following command to troubleshoot a Policy-Based Routing (PBR) issue:

R1# show ip policy
Interface   Route-map
FastEthernet0/0  PBR-MAP
Serial0/0    PBR-MAP

What does this output indicate?

Accepted Answer

The same route-map is applied to multiple interfaces, which may lead to unintended policy routing.. The output shows that the same route-map PBR-MAP is applied to both FastEthernet0/0 and Serial0/0. This could cause unexpected behavior if the route-map uses interface-specific conditions.

Answer

PBR is applied globally.

Answer

The route-map PBR-MAP is misconfigured.

Answer

PBR is only active on FastEthernet0/0.

Question 5

What is the default administrative distance for a route installed by Policy-Based Routing (PBR) using the 'set ip next-hop' command?

Accepted Answer

The administrative distance of the routing protocol that learned the route.. PBR does not change the administrative distance of the route; the route is installed with the AD of the routing protocol that learned it. The 'set ip next-hop' command does not modify AD.

Answer

0

Answer

1

Answer

120

Question 6

Which statement correctly describes the behavior of PBR when the next-hop specified in a 'set ip next-hop' command is unreachable?

Accepted Answer

The router uses the routing table to forward the packet.. If the next-hop is unreachable, PBR will fall back to the normal routing table lookup, unless a 'set ip default next-hop' is configured.

Answer

The packet is dropped immediately.

Answer

The router sends an ICMP unreachable message.

Answer

The router uses the default route if configured.

Question 7

What is the default maximum number of route-map entries that can be processed in a single PBR policy on Cisco IOS-XE?

Accepted Answer

65535. The default maximum number of route-map entries in a PBR policy is 65535, but the practical limit is often lower due to memory and performance constraints.

Answer

255

Answer

1000

Answer

Unlimited

Question 8

Which statement about PBR and the 'set interface' command is correct?

Accepted Answer

The 'set interface' command forces the packet out the specified interface, and if the interface is down, the packet is dropped.. The 'set interface' command forces the packet out a specific interface, overriding the routing table. If the interface is down, the packet is dropped unless a fallback is configured.

Answer

The 'set interface' command can only be used with point-to-point interfaces.

Answer

If the specified interface is down, the router uses the routing table.

Answer

The 'set interface' command requires a next-hop IP address to be specified.

Question 9

What is the default behavior of PBR when a 'set ip next-hop' and a 'set ip default next-hop' are both configured in the same route-map entry?

Accepted Answer

The 'set ip next-hop' is used if reachable; otherwise, the 'set ip default next-hop' is used if the routing table has no explicit route.. The 'set ip next-hop' is evaluated first. If it is reachable, it is used. If not, then the 'set ip default next-hop' is used, but only if there is no explicit route in the routing table.

Answer

The 'set ip default next-hop' is always used first.

Answer

Both are used simultaneously, and the router load-balances.

Answer

The router ignores both and uses the routing table.

Question 10

Which statement about PBR and the 'match ip address' command is correct?

Accepted Answer

It can reference a named or numbered ACL.. The 'match ip address' command references an access-list (standard or extended) to match packets based on source/destination IP addresses.

Answer

It can only match on source IP addresses.

Answer

It can match on MAC addresses.

Answer

It matches packets before routing table lookup.

Question 11

What is the default behavior of PBR when a 'set ip next-hop' is configured with an IP address that is not directly connected?

Accepted Answer

The packet is dropped.. By default, PBR requires the next-hop to be directly connected. If it is not directly connected, the packet is dropped unless 'set ip next-hop verify-availability' is used or the next-hop is reachable via a recursive lookup (which requires additional configuration).

Answer

The router performs a recursive lookup to find the next-hop.

Answer

The packet is forwarded using the routing table.

Answer

The router sends an ICMP redirect.

Question 12

Which statement about PBR and the 'set ip precedence' command is correct?

Accepted Answer

It modifies the IP header of the packet.. The 'set ip precedence' command sets the IP precedence bits in the Type of Service (ToS) field of the IP header, which can be used for QoS classification.

Answer

It sets the DSCP value.

Answer

It can only be used with 'set ip next-hop'.

Answer

It is used for load-balancing.

Question 13

What is the default action for a packet that does not match any route-map entry in a PBR policy?

Accepted Answer

The packet is forwarded using the routing table.. If no route-map entry matches, the packet is forwarded using the normal routing table lookup. PBR does not drop unmatched packets by default.

Answer

The packet is dropped.

Answer

The packet is sent to the CPU for processing.

Answer

The router sends an ICMP unreachable message.

Question 14

Drag and drop the steps to configure and verify Policy-Based Routing (PBR) into the correct order, from first to last.

Accepted Answer

Create route map with sequence number. First, define the route map with a sequence number. Next, match the interesting traffic using an ACL or prefix list. Then, set the next-hop or interface. Apply the route map under the interface in the inbound direction. Finally, verify with 'show route-map' or 'show ip policy'.

Question 15

Drag and drop the steps to troubleshoot Policy-Based Routing (PBR) adjacency or connectivity failures into the correct order, from first to last.

Accepted Answer

Verify PBR application on interface (show ip policy). Start by checking if PBR is applied on the correct interface. Then verify the route map sequence and match statements. Check the set next-hop reachability via routing table. Use 'debug ip policy' to see packet matches. Finally, test with extended ping or traceroute to confirm path.