3.6 OSPF (V2 and v3) OSPF is an interior gateway routing protocol. Specifically it is a link-state routing protocol, it runs the Dijkstra SPF Algorithm. Is a classless protocol that supports VLSM and summarization. Why use OSPF? OSPF guarantees a loop free topology. All routers in an area should have the same OSPF database thus …
Category Archives: CCIE R&S
3.3.l Implement and troubleshoot bidirectional forwarding detection
3.3.l Implement and troubleshoot bidirectional forwarding detection Bidirectional forwarding detection (BFD) is an open protocol defined in RFC 5880. BFD utilizes small UDP keep alives that are processed by asics for sub second convergence (versus using sub second hello rate that goes to control plane) If the device uses software CEF and does not have …
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3.3.f Implement and troubleshoot VRF lite
3.3.f Implement and troubleshoot VRF lite VRF allows us to have a separate routing table instance for clients Configure all of the routers, their interfaces, loopbacks, OSPF processes. Identify any gotchyas. R1: int g0/0 ip add 192.168.1.2 255.255.255.0 no shut ip ospf 1 area 0 R2: int g0/1 ip add 192.168.1.2 255.255.255.0 no shut …
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3.3.e Implement and troubleshoot passive interface
3.3.e Implement and troubleshoot passive interface RIP, OSPF, and EIGRP all support what’s known as passive-interfaces. Enabling an interface as passive will mean we will not send our hellos out on the interface, but we will advertise the interface’s network into the routing protocol. for OSPF: en conf t router ospf 1 passive-interface <default | …
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3.3.d Implement, optimize, and troubleshoot administrative distance
3.3.d Implement, optimize, and troubleshoot administrative distance This table should be memorized: You should know how to change the AD of static routes, RIP, EIGRP, OSPF, BGP Refer to the flash cards for lab scenarios. 1. Changing the AD of a static route conf t ip route x.x.x.x x.x.x.x x.x.x.x <administrative distance> #The default is …
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3.3.c Compare routing protocol types
3.3.c Compare routing protocol types 3.3.c (i) Distance Vector Distance vector routing protocols are 1 of 3 types of routing protocols. 3 of these protocols exist, RIPv1, RIPv2, IGRP, EIGRP. These protocols share very similar traits, they do NOT know the full topology of the network. Instead they only know about the directly connected neighbor. …