642-885 Exam - Deploying Cisco Service Provider Advanced Routing (SPADVOUTE)

NEW QUESTION 1
Which optionshowsthe equivalent multicast MAC address mapping of multicast address 239.210.101.190?

• A. 01:00:5e:52:65:be
• B. 01:00:5d:52:65:be
• C. 01:00:5f:52:65:be
• D. 01:00:5c:52:65:be

Answer: A

NEW QUESTION 2
Refer to the exhibit.

Based on the output of two eBGP adjacent neighbors, which command can be used to set up the default BGP timers?

• A. RP/0/0/CPU0:R1(config-bgp)#timers bgp 60 30
• B. RP/0/0/CPU0:R2(config-bgp)#timers bgp 30 60
• C. RP/0/0/CPU0:R2(config-bgp-nbr)#timers bgp 180 60
• D. RP/0/0/CPU0:R2(config-bgp)#timers bgp 60 180
• E. RP/0/0/CPU0:R1(config-bgp)#timers bgp 60 180

Answer: D

NEW QUESTION 3
DRAG DROP

• A. Mastered
• B. Not Mastered

Answer: A

Explanation:
The amount of time for the penalty to decrease to one-half of its current value - 60 Suppress a route when its penalty exceeds this value - 2400
If a flapping route penalty decreases and falls below this value , the route is unsuppressed
- 600
The maximum time a route can be suppressed – 240

SO bgp dampening 60 600 2400 240 is:
60 half life
600 reuse
2400 suppress
240 max-suppress-time

NEW QUESTION 4
DRAG DROP

• A. Mastered
• B. Not Mastered

Answer: A

Explanation:
Any Source Multicast - Uses RP's as the root of the shared tree for a multicast group, ONly (S,G) state is build between the source and the recevier, Spport SPT Switchover Source Specific Multicast - Uses (*,G) joins as well as (S,G) Joins , Requires IGMPV3 Support,
Hosts learn the multicast source address via out-of-banf mechanism
i) Dense Mode Flood-and-Prune Protocols (DVMRP / MOSPF / PIM-DM)
In dense mode protocols, all routers in the network are aware of all trees, their sources and receivers.
Protocols such as DVMRP and PIM dense mode flood “active source” information across the whole network and build trees by creating “Prune State” in parts of the topology where traffic for a specific tree is unwanted.
They are also called flood-and-prune protocols. In MOSPF, information about receivers is flooded throughout the network to support the building of trees.
Dense mode protocols are undesirable because every tree built in some part of the network will always cause resource utilization (with convergence impact) on all routers in the network (or within the administrative scope, if configured). We will not be discussing these protocols in the rest of this paper.
ii) Sparse Mode Explicit Join Protocols (PIM-SM/PIM-BiDir)
With sparse mode explicit join protocols we do not create a group-specific forwarding state in the network unless a receiver has sent an explicit IGMP/MLD membership report (or “join”) for a group. This variant of ASM is known to scale well and is the multicast paradigm we will mainly be discussing. This is the basis for PIMSparse Mode, which most multicast deployments have used to this point. This is also the basis for PIM-BiDir, which will be
increasingly deployed for MANY (sources) TO MANY (receivers) applications.
These protocols are called sparse mode because they efficiently support IP multicast delivery trees with a “sparse” receiver population – creating control plane state only on routers in the path between sources and receivers, and in PIM-SM/BiDir, the Rendezvous Point (RP). They never create state in other parts of the network. State in a router is only built explicitly when it receives a join from a downstream router or receiver, hence the name “explicit join protocols”.
Both PIM-SM and PIM-BiDir employ “SHARED TREES”, which allow traffic from any source to be forwarded to a receiver. The forwarding state on a shared tree is referred to as (*,G) forwarding state, where the * is a wild card for ANY SOURCE. Additionally, PIM- SM supports the creation of forwarding state that relates to traffic from a specific source. These are known as SOURCE TREES, and the associated state is referred to as (S, G) forwarding state SSM is the model used when the receiver (or some proxy) sends (S,G) “joins” to indicate that it wants to receive traffic sent by source S to group G. This is possible with IGMPv3/MLDv2 “INCLUDE” mode membership reports. We therefore refer to this model as the Source-Specific Multicast (SSM) model. SSM mandates the use of an explicit-join protocol between routers. The standard protocol for this is PIM-SSM, which is simply the subset of PIM-SM used to create (S,G) trees. There are no shared trees (*,G) state in SSM. Multicast receivers can thus “join” an ASM group G, or “join” (or more accurately “subscribe” to) an SSM (S, G) channel. To avoid having to repeat the term “ASM group or SSM channel”, we will use the term (multicast) flow in the text, implying that the flow could be an ASM group or an SSM channel

NEW QUESTION 5
When a BGP route reflector receives an IBGP update from a non-client IBGP peer, the route reflector will then forward the IBGP updates to which other router(s)?

• A. To the other clients only
• B. To the EBGP peers only
• C. To the EBGP peers and other clients only
• D. To the EBGP peers and other clients and non-clients

Answer: C

NEW QUESTION 6
When implementing interdomain multicast routing, which mechanism can be used to advertise multicast sources in one domain to the other domains, allowing the RPs to build interdomain multicast distribution trees?

• A. Multiprotocol BGP
• B. PIM
• C. MSDP
• D. Auto RP
• E. BSR
• F. MLD

Answer: C

Explanation:
Multicast Source Discovery Protocol
Multicast Source Discovery Protocol (MSDP) is a mechanism to connect multiple PIM sparse-mode domains.
MSDP allows multicast sources for a group to be known to all rendezvous point(s) (RPs) in different domains.
Each PIM-SM domain uses its own RPs and need not depend on RPs in other domains. An RP in a PIM-SM domain has MSDP peering relationships with MSDP-enabled routers in other domains.
Each peering relationship occurs over a TCP connection, which is maintained by the underlying routing system.
MSDP speakers exchange messages called Source Active (SA) messages. When an RP learns about a local active source, typically through a PIM register message, the MSDP process encapsulates the register in an SA message and forwards the information to its peers. The message contains the source and group information for the multicast flow, as well as any encapsulated data. If a neighboring RP has local joiners for the multicast group, the RP installs the S, G route, forwards the encapsulated data contained in the SA
message, and sends PIM joins back towards the source. This process describes how a multicast path can be built between domains.

NEW QUESTION 7
Which command set implements BGP support for NSF/SSO on Cisco IOS XE between a PE and a route reflector?

• A. On RR:router bgp 300no synchronizationbgp log-neighbor-changesbgp graceful-restart restart-time 120 bgp graceful-restart stalepath-time 360 bgp graceful-restartneighbor 10.20.20.2 remote-as 200neighbor 10.20.20.2 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.2 activateneighbor 10.20.20.2 send-community both neighbor 10.20.20.2 route-reflector-client exit-address-familyOn PE:router bgp 300no synchronizationbgp log-neighbor-changesbgp graceful-restart restart-time 120 bgp graceful-restart stalepath-time 360 bgp graceful-restartneighbor 10.20.20.1 remote-as 300neighbor 10.20.20.1 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.1 activateneighbor 10.20.20.1 send-community both exit-address-family!
• B. On RR:router bgp 300no synchronizationbgp log-neighbor-changesbgp graceful-restart restart-time 120 bgp graceful-restart stalepath-time 360 bgp graceful-restartneighbor 10.20.20.2 remote-as 200neighbor 10.20.20.2 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.2 activateneighbor 10.20.20.2 send-community both neighbor 10.20.20.2 route-reflector-client exit-address-familyOn PE:router bgp 300no synchronizationbgp log-neighbor-changes neighbor 10.20.02.1 remote-as 300neighbor 10.20.20.1 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.1 activateneighbor 10.20.20.1 send-community both exit-address-family!
• C. On RR:router bgp 300no synchronizationbgp log-neighbor-changesbgp graceful-restart restart-time 120 bgp graceful-restart stalepath-time 360 bgp graceful-restartneighbor 10.20.20.2 remote-as 200neighbor 10.20.20.2 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.2 activateneighbor 10.20.20.2 send-community both neighbor 10.20.20.2 route-reflector-client exit-address-familyOn PE:router bgp 300no synchronizationbgp log-neighbor-changes neighbor 10.20.20.1 remote-as 300neighbor 10.20.20.1 update-source Loopback0 neighbor 10.20.20.1 ha-mode ssono auto-summary!address-family vpnv4 neighbor 10.20.20.1 activateneighbor 10.20.20.1 send-community both exit-address-family!
• D. On RR:router bgp 300no synchronizationbgp log-neighbor-changes neighbor 10.20.20.2 remote-as 200neighbor 10.20.20.2 update-source Loopback0 neighbor 10.20.20.2 ha-mode ssono auto-summary!address-family vpnv4 neighbor 10.20.20.2 activateneighbor 10.20.20.2 send-community both neighbor 10.20.20.2 route-reflector-client exit-address-familyOn PE:router bgp 300no synchronizationbgp log-neighbor-changes neighbor 10.20.20.1 remote-as 300neighbor 10.20.20.1 update-source Loopback0 neighbor 10.20.20.1 ha-mode ssono auto-summary!address-family vpnv4 neighbor 10.20.20.1 activateneighbor 10.20.20.1 send-community both exit-address-family!
• E. On RR:router bgp 300no synchronizationbgp log-neighbor-changesneighbor 10.20.20.2 remote-as 200neighbor 10.20.20.2 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.2 activateneighbor 10.20.20.2 send-community both neighbor 10.20.20.2 route-reflector-client exit-address-familyOn PE:router bgp 300no synchronizationbgp log-neighbor-changesbgp graceful-restart restart-time 120 bgp graceful-restart stalepath-time 360 bgp graceful-restartneighbor 10.20.20.1 remote-as 300neighbor 10.20.20.1 update-source Loopback0 no auto-summary!address-family vpnv4 neighbor 10.20.20.1 activateneighbor 10.20.20.1 send-community both exit-address-family!

Answer: A

NEW QUESTION 8
Which two statements regarding Auto RP operations and implementations are correct? (Choose two.)

• A. Candidate RPs send RP announcements to the 224.0.1.39 multicast group, and the mapping agents send RP discovery messages to the 224.0.1.40 multicast group
• B. Every PIM-SM router must be configured with the RP mapping agent IP address
• C. Candidate RPs learn the IP address of the mapping agents via periodic RP discovery messages
• D. Administrative scoping can be configured to limit the scope of the RP announcements
• E. A Reverse Path Forwarding check is done on the RP discovery messages
• F. RP discovery messages are flooded hop by hop throughout the network as multicast to the all PIM routers multicast group with a TTL of 1

Answer: AD

Explanation:
Auto-RP
Automatic route processing (Auto-RP) is a feature that automates the distribution of group- to-RP mappings in a PIM network. This feature has these benefits:
It is easy to use multiple RPs within a network to serve different group ranges. It allows load splitting among different RPs.
It facilitates the arrangement of RPs according to the location of group participants.
It avoids inconsistent, manual RP configurations that might cause connectivity problems. Multiple RPs can be used to serve different group ranges or to serve as hot backups for each other. To ensure that Auto-RP functions, configure routers as candidate RPs so that they can announce their interest in operating as an RP for certain group ranges. Additionally, a router must be designated as an RP-mapping agent that receives the RP- announcement messages from the candidate RPs, and arbitrates conflicts. The RPmapping agent sends the consistent group-to-RP mappings to all remaining routers. Thus, all routers automatically determine which RP to use for the groups they support auto- rp candidate-rp
To configure a router as a Protocol Independent Multicast (PIM) rendezvous point (RP) candidate that sends messages to the well-known CISCO-RP-ANNOUNCE multicast group
(224.0.1.39), use the auto-rp candidaterp command in PIM configuration mode. To return to the default behavior, use the no form of this command. auto-rp candidate-rp type interface-path-id scope ttl-value [ group-list access-listname ] [ interval seconds ] [bidir] no auto-rp candidate-rp type interface-path-id scope ttl-value [ group-list access-listname] [ interval seconds ] [bidir]

NEW QUESTION 9
A service providerrequests more details about the recent Inter-AS MPLS VPN Option B configuration that was recently deployed. Consider this configuration:
router bgp 3717
address-family vpnv4 unicast retain route-target all
commit
!
Which option describes why this particular command is needed?

• A. The ASBRcan have many working customer VRFs, so this configuration ensures the coexistence of all the route-target extended communities that belong to the all ASBR- terminated customer VRFs.
• B. When implementing the Inter-AS Option B MPLS VPN solution, all the route targets that are transmitted over the Inter-AS links need an ASBR local database to forward thecustomer traffic correctly.
• C. The Inter-AS Option B design implements VPNv4 communication over the Inter-AS link, hence the requirement for a route-target association for each customer VPN connected across two or more ASs.
• D. In the Inter-AS Option B design, no local VRF is maintained on the ASBR routers,so the default behavior of the operating system is to deny any route-target extended community that is encoded in the incoming iBGP update
• E. This configuration permits VPNv4 communication by accepting the iBGP updates even if no route targets are configured locally.

Answer: D

NEW QUESTION 10
Which statement is correct regarding using the TTL threshold to define the delivery boundaries of multicast traffic?

• A. If a packet TTL is less than the specified TTL threshold, the packet is forwarded out of the interface
• B. If a packet TTL is greater or equal to the specified TTL threshold, the packet is forwarded out of the interface
• C. If a packet TTL is equal to the specified TTL threshold, the packet is dropped
• D. When a multicast packet arrives, the TTL threshold value is decremented by 1. If the resulting TTL threshold value is greater than or equal to 0, the packet is dropped

Answer: B

NEW QUESTION 11
What is enabled by default on Cisco IOS-XR routers and cannot be disabled?

• A. SSH server
• B. Multicast routing
• C. IPv4 and IPv6 CEF
• D. IPv6 routing
• E. CDP
• F. BFD

Answer: C

Explanation:
Before using the BGP policy accounting feature, you must enable BGP on the router (CEF is enabled by default).

NEW QUESTION 12
Refer to the Cisco IOS DHCPv6 configuration shown in the exhibit.

Which statement is correct?

• A. The configuration is missing a command under interface Gi0/1 to indicate to the attached hosts to use stateful DHCPv6 to obtain their IPv6 addresses
• B. The IPv6 router advertisements indicate to the attached hosts on the Gi0/1 interface to get other information besides their IPv6 address via stateless auto configuration
• C. The IPv6 DHCPv6 server pool configuration is misconfigured
• D. The DNS server address can also be imported from another upstream DHCPv6 server

Answer: A

Explanation:
Server Configuration
In Global Configuration Mode ipv6 unciast-routing
ipv6 dhcp pool <pool name>
address prefix <specify address prefix> lifetime <infinite> <infinite> dns-server <specify the dns server address>
domain-name <specify the domain name> exit
In Interface Configuration Mode
ipv6 address <specify IPv6 Address>
ipv6 dhcp server <server name>rapid-commit Client Configuration
In Global Configuration Mode enable
configure terminal ipv6 unicast-routing
In Interface Configuration Mode ipv6 address dhcp rapid commit ipv6 enable
exit

NEW QUESTION 13
Refer to the Cisco IOS-XR configuration exhibit.

The Cisco IOS-XR router is unable to establish any PIM neighbor relationships. What is wrong with the configuration?

• A. The configuration is missing:interface gi0/0/0/0 ip pim sparse-mode interface gi0/0/0/1 ip pim sparse-mode interface loopback0 ip pim sparse-mode
• B. The configuration is missing: multicast-routingaddress-family ipv4 interface gi0/0/0/0 enableinterface gi0/0/0/1 enable
• C. The auto-rp scoping configurations should be set to 1 not 16
• D. The RP address has not been configured using the rp-address router PIM configuration command
• E. PIM defaults to dense mode operations only, so PIM sparse mode must be enabled using the pim sparse-mode router PIM configuration command

Answer: B

NEW QUESTION 14
Refer to the exhibit.

Given the partial BGP configuration, which configuration correctly completes the Cisco IOS-XR route reflector configuration where both the 1.1.1.1 and 2.2.2.2 routers are the clients and the 3.3.3.3 router is a non-client IBGP peer?

• A. neighbor 1.1.1.1remote-as 65123 route-reflector-client neighbor 2.2.2.2remote-as 65123 route-reflector-client neighbor 3.3.3.3remote-as 65123
• B. neighbor 1.1.1.1 address-family ipv4 unicast remote-as 65123route-reflector-client neighbor 2.2.2.2address-family ipv4 unicast remote-as 65123route-reflector-client neighbor 3.3.3.3address-family ipv4 unicast remote-as 65123
• C. neighbor 1.1.1.1remote-as 65123address-family ipv4 unicast route-reflector-client neighbor 2.2.2.2remote-as 65123address-family ipv4 unicast route-reflector-client neighbor 3.3.3.3remote-as 65123
• D. neighbor 1.1.1.1 remote-as 65123neighbor 1.1.1.1 route-reflector-clientneighbor 2.2.2.2 remote-as 65123neighbor 2.2.2.2 route-reflector-clientneighbor 3.3.3.3 remote-as 65123

Answer: C

NEW QUESTION 15
Which additional feature is provided using MLDv2 that is not available in MLDv1?

• A. Multicast Address Specific Queries
• B. Source filtering
• C. Done messages
• D. Report messages

Answer: B

Explanation:
• PIM-SSM is made possible by IGMPv3 and MLDv2. Hosts can now indicate interest in specific sources using IGMPv3 and MLDv2. SSM does not require a rendezvous point (RP) to operate.

NEW QUESTION 16
A network architect is responsible for the company's multicast network domain design. Which multicast component acts as a meeting place for sources and receivers?

• A. multicast shared tree
• B. multicast distribution point
• C. multicast rendezvous point
• D. multicast source tree

Answer: C

NEW QUESTION 17
A network engineer must deploy an iBGP-based cloud region configuration by means of templates to reduce the overall BGP CLI required. Which three commands represent a basic configuration for a BGP peer session template on a regular Cisco IOS instance? (Choose three.)

• A. template peer-session session-template-name
• B. remote-as as-number
• C. neighbor-family config template
• D. peer-family config template
• E. as-override
• F. timers keepalive-interval hold-time

Answer: ABF

NEW QUESTION 18
In secure multicast, which protocol is used to distribute secure keys to a multicast group?

• A. ISAKMP
• B. RSA
• C. IPsec
• D. GDOI
• E. SKIP

Answer: D

NEW QUESTION 19
Which two features are used to provide high availability multicast? (Choose two.)

• A. BFD
• B. NSF/SSO
• C. PIM NSR
• D. PIM triggered join
• E. IGMP triggered report
• F. MSDP

Answer: BD

Explanation:
Triggered joins are sent when the primary or the secondary RPF information changes. No RPF change prunes are sent for MoFRR streams.
mofrr
To perform a fast convergence (multicast-only fast reroute, or MoFRR) of specified routes/flows when a failure is detected on one of multiple equal-cost paths between the router and the source, use the mofrr command under PIM configuration mode.
mofrr rib acl_name no rib acl_name

NEW QUESTION 20
Which informationdoes the multicast supported router need to forward the multicast traffic over the source or shared tree?

• A. source address
• B. multicast address
• C. destination address
• D. mGRE headers
• E. MDT Data

Answer: C

NEW QUESTION 21
In Cisco IOS-XR, the ttl-security command is configured under which configuration mode?

• A. RP/0/RSP0/CPU0:P2(config)#
• B. RP/0/RSP0/CPU0:P2(config-bgp)#
• C. RP/0/RSP0/CPU0:P2(config-bgp-nbr)#
• D. RP/0/RSP0/CPU0:P2(config-bgp-af)#
• E. RP/0/RSP0/CPU0:P2(config-bgp-nbr-af)#

Answer: C

Explanation:
http://packetlife.net/blog/2009/nov/23/understanding-bgp-ttl-security/

NEW QUESTION 22
Which multicast routing protocol is most optimal for supporting many-to-many multicast applications?

• A. PIM-SM
• B. PIM-BIDIR
• C. MP-BGP
• D. DVMRP
• E. MSDP

Answer: B

Explanation:
PIM-Bidirectional Operations
PIM Bidirectional (BIDIR) has one shared tree from sources to RP and from RP to receivers. This is unlike the PIM-SM, which is unidirectional by nature with multiple source trees - one per (S, G) or a shared tree from receiver to RP and multiple SG trees from RP to sources.
Benefits of PIM BIDIR are as follows:
• As many sources for the same group use one and only state (*, G), only minimal states are required in each router.
• No data triggered events.
• Rendezvous Point (RP) router not required. The RP address only needs to be a routable address and need not exist on a physical device.

NEW QUESTION 23
Refer to the exhibit.




Which three statements regarding the BGP operations are correct? (Choose three)

• A. PE5 is the route reflector with P1 and PE6 as its client
• B. PE5 is using the IS-IS route to reach the BGP next-hop for the 172.16.66.0/24 prefix
• C. PE5 has BGP route dampening enabled
• D. The BGP session between PE5 and P1 is established using the loopback interface andnext-hop-self
• E. The BGP session between PE5 and CE5 is established using the loopback interface

Answer: ACD

NEW QUESTION 24
An engineer is providing DNS for IPv6 over a currently working IPv4 domain. Which three changes are needed to offer DNS functionality for IPv6? (Choose three.)

• A. Define a new record that stores the 128-bit IPv6 address.
• B. Expand the existing IP address record to allow for 128 bits.
• C. Define the IPv6 equivalent of the in-addr.arpa.com domain of the IPv4 PTR.
• D. Modify the in-addr.arpa.com domain of the IPv4 PTR.
• E. Change the query messages.
• F. Transport IPv6 query messages by using UDP.
• G. Transport IPv6 query messages by using TCP.

Answer: ACE

NEW QUESTION 25
......