They do not work well in networks that require special heirarchical designs.
They are aware of the complete network topology.
They pass their entire routing tables to their directly connected neighbors only.
They offer rapid convergence times in large networks.
They do not include subnet masks in their routing updates.
OSPF elects designated routers on multiaccess links.
RIP does not support classless routing.
EIGRP supports unequal cost load balancing.
EIGRP uses broadcast traffic to establish adjacencies with its neighbors.
RIP does not advertise a route beyond a hop count of 15.
It reduces the update timer to 15 seconds if there are more then 10 routes.
It uses triggered updates to announce network changes if they happen in between the periodic updates.
It uses random pings to detect if a pathway is down and therefore is preemptive on finding networks that are down.
It uses multicast instead of broadcast to send routing updates.
Annapolis is a 2611 router that is connected to the S0/0 interface of the Montgomery router.
All of the routers are connected to Montgomery through an Ethernet switch.
Montgomery has Layer 2 connectivity with Cumberland.
Layer 3 connectivity is operational for all of the devices listed in the Device ID column.
Brant, Fisherman, and Potomac are directly connected to Montgomery.
Static route to 10.1.0.0/22
RIP route to 10.1.0.0/23
RIP route to 10.1.0.0/24
0.0.0.0/0 via 192.168.0.1
All of the 192.168.x.0 networks will be in the routing table.
Routes to networks 192.168.1.0/24, 192.168.2.0/24, and 192.168.3.0/24 will be in the routing table.
The routing table will be empty because routes and dynamic routes have not been configured.
A default route is automatically installed in the routing table to allow connectivity between the networks.
OSPF interval timers mismatch
Gateway of last resort not redistributed
Interface network type mismatch
No loopback interface configured
Inconsistent authentication configuration
Reboot the routers.
Change the OSPF process ID on all of the routers to 0.
Check to see if the cable is loose between BOS and JAX.
Check to see if CDP packets are passing between the routers.
Use show and debug commands to determine if hellos are propagating.
192.168.10.5 and 192.168.10.9 are feasible successors
Neighbors 192.168.10.9 and 192.168.10.5 have auto summary disabled
Router 3 is load balancing traffic to the 172.16.3.0 network across its serial interfaces
All interfaces shown on Router3 are in the passive state and will not send EIGRP advertisements
The address assigned to the Ethernet0 interface of Router1 is a broadcast address for that subnetwork.
The subnetwork configured on the serial link between Router1 and Router2 overlaps with the subnetwork assigned to Ethernet0 of Router3.
The subnetwork assigned to the Serial0 interface of Router1 is on a different subnetwork from the address for Serial0 of Router2.
The subnetwork assigned to Ethernet0 of Router2 overlaps with the subnetwork assigned to Ethernet0 of Router3.
Used to confirm receipt of certain types of OSPF packets
Used to establish and maintain adjacency with other OSPF routers
Used to request more information about any entry in the BDR
Used to announce new OSPF information and to reply to certain types of requests
Domain name resolution
Learn about directly connected networks
Send hello to discover neighbors and form adjacencies
Choose successors and feasible successors to populate the topology table
Flood LSPs to all neighbors informing them of all known networks and their link states
As new neighbors are discovered, entries are placed in a neighbor table.
If the feasible successor has a higher advertised cost than the current successor route, then it becomes the primary route.
If hello packets are not received within the hold time, DUAL must recalculate the topology.
The reported distance is the distance to a destination as advertised by a neighbor.
EIGRP maintains full knowledge of the network topology in the topology table and exchanges full routing information with neighboring routers in every update. EIGRP builds one routing table that contains routes for all configured routed protocols.
Router_A(config-router)# ospf redistribute default-route
Router_B(config-router)# ospf redistribute default-route
Router_A(config-router)# default-information originate
Router_B(config-router)# default-information originate
Router_B(config-router)# ip ospf update-default
Autonomous system number
A(config)# router rip A(config-router)# passive-interface S0/0
B(config)# router rip B(config-router)# network 192.168.25.48 B(config-router)# network 192.168.25.64
A(config)# router rip A(config-router)# no network 192.168.25.32
B(config)# router rip B(config-router)# passive-interface S0/0
A(config)# no router rip
All routing protocols use the same metrics.
EIGRP uses bandwidth as its only metric.
Routers compare metrics to determine the best route.
The larger metric generally represents the better path.
Router4 will learn about the failed route 30 seconds later in the next periodic update.
Split horizon will prevent Router4 from fowarding packets to the 10.0.0.0 network until the holddown timer expires.
Router5 immediately flushes the unreachable route from its routing table.
Router5 will send Router4 a triggered update with a metric of 16 for network 10.0.0.0.
R1(config-router)# network 172.16.0.0 0.0.0.255 area 0
R1(config-router)# network 172.16.0.0 0.0.3.255 area 0
R1(config-router)# network 172.16.0.0 0.0.15.255 area 0
R1(config-router)# network 172.16.0.0 0.0.31.255 area 0
The Dijkstra algorithm will calculate the feasible successor.
DUAL will query neighbors for a route to network 192.168.1.0.
Neighbor 172.16.3.2 will be promoted to the feasible successor.
Traffic destined to the 192.168.1.0 network will be dropped immediately due to lack of a feasible successor.
The packet will be dropped.
The packet will be forwarded to the gateway of last resort.
The packet will match the 192.168.0.0 network and be forwarded out Serial 0/0.
The packet will most closely match the 192.168.0.8 subnet and be forwarded out Serial 0/1.
The router modifies the TTL field, decrementing it by one.
The router changes the source IP to the IP of the exit interface.
The router maintains the same source and destination IP.
The router changes the source physical address to the physical address of the exit interface.
The router sends the packet out all other interfaces, besides the one it entered the router on.