The first preference for an OSPF router ID is an explicitly configured 32-bit address. This address is not in the routing table and is not defined by the network command.
In this context, what are the two purposes of an OSPF router ID?
(Choose two out. )
- to allow the SPF algorithm to determine the cheapest path to remote networks.
- to facilitate the establishment of network convergence.
- to the contained therein Routers to uniquely identify the OSPF domain*
Also, what are two reasons preventing two routers from forming an OSPFv2 neighborhood, choose two? (Choose two.)
- a mismatched Cisco IOS version being used.
- OSPF hello or dead timer mismatch.
- mismatched subnet masks on the link interfaces.
- Use of private IP addresses on the link interfaces.
In this regard, how is the router ID for an OSPFv3 -Router discovered?
In OSPFv3 and OSPF version 2, the router uses the 32-bit IPv4 address to select the router ID for an OSPFv3 process. If an IPv4 address is present when OSPFv3 is enabled on an interface, that IPv4 address will be used for the router ID.
For reasons to create a multi-range OSPF network, choose You two?
- to simplify the configuration.
- to ensure that a range is used to connect the network to the Internet to connect.
- to reduce SPF calculations*
- to provide areas in the network for routers that are not running OSPF.
What is the format of the router ID when OSPF is enabled? Router?
The OSPF router ID is used to assign a unique identity to the OSPF router. The OSPF router ID is an IPv4 address (32-bit binary number) assigned to each router running the OSPF protocol.
What are the three requirements for two OSPFv2 routers form an adjacency?
What three requirements are necessary for two OSPFv2 routers to form an adjacency? (Choose three.) – The OSPF hello or dead timers on each router must match. – The two routers must include the connection network between the routers in an OSPFv2 network command. – The subnet masks of the connection interface must match.
Which statement describes a multi-area OSPF network?
Which statement describes a multi-area OSPF network? It consists of several network areas that are linked together. It requires a three-tier hierarchical network design approach. It has a core backbone area with other areas connected to the backbone area.
What three OSPF states are involved when two routers form a neighborhood?
Down, Init, and Two-way states are involved in the phase of establishing neighboring router adjacencies. If Router C’s priority is changed to 255, it becomes the DR. If the DR fails, the new DR is Router B. If a new router with a higher priority is added to this network, it becomes the DR.
What address will Eigrp use for IPv6 as a router ID?
6 is TCP, 17 is UDP, 88 is EIGRP and 89 is OSPF. What address does EIGRP for IPv6 use as the router ID? EIGRP for IPv6 uses the same router ID as EIGRP for IPv4. The 32-bit number can be configured with the router-id command or assigned automatically from the highest IPv4 address on an enabled interface.
How is the designated router chosen in OSPF?
Two rules are used to select a DR and BDR: Routers with the highest OSPF priority become a DR. By default, all routers have priority 1. In the event of a tie, the router with the highest router ID wins the election.
What does the SPF algorithm think is the best path to a network?
What does the SPF algorithm think is the best path to a network? The path containing the links with the fastest cumulative bandwidth. EIGRP supports routing of various network layer protocols while OSPF only supports routing of IP-based protocols.
What is an advantage of multiarea OSPF routing?
What is an advantage of multiarea –OSPF routings? a Topology changes in one area do not result in SPF recalculations in other areas. b By default, automatic route summarization occurs between areas. c Routers in all areas share the same link-state database and have a complete picture of the entire network.
What’s a downside to using auto-Eigrp summarization?
What is a downside to using EIGRP’s auto-summarization? It creates inconsistent routing when the network has non-contiguous networks. Automatic summarization does not prevent routing table convergence, nor does it increase the size of routing updates. Fill in the blank.
What is the best way to manually configure an OSPF router ID?
You can manually configure a router ID by using the command router-id enter ip-address Router configuration mode, where ip-address is the 32-bit value you want OSPF to use as the router ID.
What is the purpose of the Eigrp-Null0 summary route ?
What is the purpose of the EIGRP Null0 aggregation route? To prevent routing loops for destination networks that don’t actually exist but are included in a summary route.
What is the router’s OSPF process ID?
The process ID is the ID of the OSPF process to which the interface belongs. The process ID is local to the router, and two neighboring OSPF routers can have different OSPF process IDs.
What does the router ID mean?
The router ID ID is used by BGP and OSPF to identify the routing device a packet originated from. The router ID is usually the IP address of the local routing device. If you do not configure a router ID, the IP address of the first interface that comes online will be used.
Does the OSPF router ID have to be assigned to an interface?
All routers requires a router ID to join an OSPF domain. The router ID can be set by an administrator or assigned automatically by the router. If the router uses the highest IPv4 address for the router ID, the interface does not have to be OSPF-aware.
What IPv6 address is used by OSPFv3 as the next hop?
OSPFv3 uses a router‘s link-local IPv6 address (remember in Chapter 2 that these addresses always start with FF80::/10) as source address and as next-hop addresses.
How do I get a router ID?
If you want to change the router ID setting, do the following:
- Go to the global configuration context; the CLI prompt looks something like this:
- If OSPF is not enabled, go to step 3; If OSPF is enabled, use no router ospf to disable OSPF operation.
- Use ip router-id ip-addr to specify a new router ID.
How do I find my OSPF router ID?
Follow these steps to determine if there is a duplicate router ID: Run the show ip ospf database router x.x.x.x on the router that should have this ID. This command displays the contents of a router LSA (Type 1) that advertises a router and all of its directly connected interfaces.