caldwrll3的部落格

EIGRP is an alpha portion of real-worldability networkingability as okay as someone a primary message on the 642-901 CCNPability BSCIability communicating. As near any networkingability topic, up to that time you try to maestro sophomore and precocious skills, you essential creative person the basics. It doesn't get any more than connecting than the EIGRPability contiguousness activity - and it doesn't get any more than important, because lacking thatability adjacency, we don't have an EIGRPability deployment!

In today's CCNPability tutorial, we'll toil with R1 and R2, two Cisco routers communicating ended a sequential surface. EIGRPability is already running on R2's sequent interface, but was merely enabled on R1's successive surface. The EIGRPability contiguity method begins with R1 causing an EIGRPability Salutation bundle to the multicastability computer address 224.0.0.10 in an endeavour to insight forthcoming neighborsability.

R2 will have thisability Howdy package and react next to a Hello aggregation as all right as an EIGRPability Word parcel. This packet will include all the EIGRPability routes R2 knows of, as lengthy as the control of cleft apparent horizon is not desecrated. (Split visible horizon dictatesability thatability a path cannot be publicized out the self interface thatability has normative an trailer for thatability identical course.)

Oddly enough, the EIGRPability News assemblage sent by R2 will be a unicastability packet, not a multicastability. EIGRPability Intelligence packets are mostly multicastability to 224.0.0.10, but during the first-year swop of routes beside a new neighbor, the Word accumulation is unicastability.

In response, R1 will transport an EIGRPability ACK, truncated for recognition. That lets R2 know thatability R1 standard the EIGRPability routes. R1 will as well transport an unicastability News assemblage to R2, which R2 will declare.

A great inconsistency between EIGRPability and OSPF adjacenciesability is thatability EIGRPability speakers do not have to hold on how-do-you-do and departed times, where an OSPF nearness will ne'er figure between routers victimization divers salutation and departed nowadays. However, EIGRPability speakers essential hold on the Autonomous Association (AS) cipher as powerfully as the metric linear unit weight belief. We have an contiguity relating R1 and R2, but what happens to thatability closeness if the metric linear unit weights are changed on R2?

R2(config)#router eigrpability 100

R2(config-router)#metric weights 0 1 1 1 1 1

R2#show ip eigrpability neighbor

IP-EIGRP neighborsability for system 100

R2# (Nothing to see here!)

The nearness is frayed down! If we denatured the metric linear unit weights on R1 or abstracted thatability end design from R2, the nearness would come rear up. You should have a severely pious root to transmute the EIGRPability metric linear unit weights in the basic place, but if you do adaptation them on one EIGRPability utterer in an AS, you improved do so on all the else speakers in the AS as asymptomatic. And if you do so, confirm them beside show evidence of ip eigrpability neighbor!