The OSPF RFC 3623 Graceful Restart feature allows you to configure IETF NSF in ultivendor networks. When using OSPF Graceful Restart， which mechanism is used tocontinue forwarding packets during a switchover？（）

A . It provides dynamic neighbor discovery. B . It detects unreachable neighbors in 90 second intervals. C . It maintains neighbor relationships. D . It negotiates correctness parameters between neighboring interfaces. E . It uses timers to elect the router with the fastest links as the designated router. F . It broadcasts hello packets throughout the internetwork to discover all routers that are running OSPF

A . The peer router immediately removes the BGP routers that it learned from the restarting router from itsBGP routing tables. B . The router establishes BGP sessions with other routers and relearns the BGP routes from others that are also capable of graceful restart. The restarting router waits to receive updates from the neighboringrouters. When the neighboring routers send end-of-RIB messages to indicate that they are donesending updates，the restarting router starts sending its own updates. C . The peer router sends an end-of-RIB message to the restarting router. D . The restarting router removes any stale prefixes after the timer for stale entries expires. E . The restarting router does not remove any stale prefixes after the timer for stale entries expires.

A . 1 B . 10 C . 1562 D . 64000 E . 128000

A . It confines network instability to a single area of network. B . It increases the routing overhead of the network C . It supports VLSM D . It routes between Autonomous Systems. E . It allows extensive control of routing updates F . None of the above

A . Traffic forwarded from R2 to or through R1 will continue to be forwarded based on the forwarding table state at the time of the reload. B . R2 will continue to forward traffic to R1， but R1 will drop the traffic because its neighbor adjacency with R2 has failed. C . R2 will continue forwarding traffic to and through R1， but R1 will drop this traffic because it is not capable of maintaining its forwarding state. D . All the traffic R2 is forwarding to or through R1 will be dropped while OSPF rebuilds its neighbor adjacency and forwarding tables.

A . 121 B . 115 C . 110 D . 101 E . 151 F . 51

A . Amplification is prevented if global changes have only a local effect as opposed to systems in which global changes have a local effect B . Amplification is prevented if local changes have only a local effect as opposed to system inwhich localchange have a global effect C . Internet domain does not suffer from“The Amplification Principle”as BGP takes care of misbehaving advertisers D . None of the above

A . It provides dynamic neighbor discovery B . It detects unreachable neighbors in 90 second intervals C . It maintains neighbor relationships D . It negotiates correctness parameters between neighboring interfaces E . It uses timers to elect the router witch the fastest links as the designated router F . It broadcasts hello packets throughout the internetwork to discover all routers that are running OSPF

A . Reverse Path Forwarding B . Hardware-based forwarding C . UDP forwarding D . Layer 2 Forwarding

A .  224.0.4.86 B .  224.4.86.0 C .  233.1.200.0 D .  239.2.213.0 E .  239.4.5.6

A . Inbound distribute-list is configured under the ospf process and it is denying x.x.x.x B . ASBR origination the LSA is not reachable C . Route to the Forwarding Address in not an internal OSPF route D . Route to the Forwarding Address is an internal OSPF route E . Route to the ASBR does not follow the same path as the one to the Forwarding Addre

A . Each OSPF area requires a loopback interface to be configured. B . Areas may be assigned any number from 0 to 65535. C . Area 0 is called the backbone area. D . Hierarchical OSPF networks do not require multiple areas. E . Multiple OSPF areas must connect to area 0. F . Single area OSPF networks must be configured in area 1.

A . It supports VLSM. B . It is used to route between autonomous systems. C . It confines network instability to one area of the network. D . It increases routing overhead on the network. E . It allows extensive control of routing updates. F . It is simpler to configure than RIP v2.

A .  Improves convergence of the multicast network due to enhanced RPF checks B .  Simplifies the number of control plane protocols over other RP redundancy methods C .  Eliminates the use of Protocol Independent Multicast （PIM） in the topology D .  Increases the administrative distances in Multicast Source Discovery Protocol （MSDP） configuratio

A . Graceful restart allows session information recovery without disruption to the network. B . A node can perform a graceful restart to help a neighbor recover its state. The label bindings are kepton state information， which helps the failed node recover faster and does notaffect the current for wardtraffic. C . Graceful restart allows a node to recover state from its neighbor when there is no RP or before thedevice undergoes SSO. D . Graceful restart does not allow session information recovery. E . During a graceful restart， the router removes any stale prefixes after a timer for stale entries expire

A .  It supports VLSM. B .  It is used to route between autonomous systems. C .  It confines network instability to one area of the network. D .  It increases routing overhead on the network. E .  It allows extensive control of routing updates. F .  It is simpler to configure than RIP v2.

A . Router(config-router)# network 192.168.10.0 0.0.0.255 0 B . Router(config-router)# network 192.168.10.0 0.0.0.255 area 0 C . Router(config-router)# network 192.168.10.0 255.255.255.0 area 0 D . Router(config)# router ospf 0 E . Router(config)# router ospf 1

A . The peer router sends an end-of RIB message to the restarting router B . The peer router immediately removes the BGP routes that it learned from the restarting router from its BGP routing table C . The restarting router does not remove any stale prefixes after the timer for stale entries expires D . The router establishes BGP sessions with other routers and relearns the BGP routes from other routers that are also capable of graceful restart. The restarting router waits to receive updates from the neighboring routers. When the neighboring routers send end-of-RIB messages to indicate that they are done sending updates， the restarting router starts sending its own updates E . The restarting router removes any stale prefixes after the timer for stale entries expire

A . Ensure that an interface has been configured with an IP address B . Ensure that IP classless is enabled C . Ensure that the interfaces can ping their directly connected neighbors D . Ensure that an interface has been configured with an IP address and is u

A .  OSPF stub areas increase the size of the LSDB with the addition of Type 3 and 5 LSAs B .  OSPF not so stubby areas are particularly useful as a simpler form of summarization C .  OSPF stub areas are always insulated from external changes D .  OSPF totally stubby cannot distinguish among ABRs for the best route to destinationsoutsidethe areas E .  OSPF stub areas can distinguish among ASBRs for destinations that are external to the OSPFdomai

A . Let the metrics default. B . Use each redistributed route's OSPF metric using the redistribute command's metric transparent keywords. C . Set the metric using the default - metric router subcommand. D . Redistribution is not allowed between two OSPF p rocesses.

A .  All cluster resources halt on Node ’B’，and one or both surviving nodes will gracefully acquire the resources. B .  All cluster processes halt on Node ’B’，the cluster resources remain active，and the remaining  nodes take no action. C .  All cluster processes stay active on Node ’B’，cluster resources are halted，and the remaining nodes take no action. D .  All cluster resources will stop，cluster processes halt on Node ’B’，and the remaining cluster nodes take no action.

<img src='https://img2.soutiyun.com/ask/uploadfile/2019-03-27/3ce23df98edd74223603f0cf62587cff.jpg' /> A．A B．B C．C D．D

A．OSPF B．MPLS LDP C．GP D．Static routes 此题为多项选择题。