CCIE R&S Advanced Technologies Class v4.5 - OSPF Network Type Point-to-Multipoint Non-Broadcast, OSPF Per Neighbor Cost

Transcript

1	Introduction	0h 43m
2	Using the Cisco Documentation	0h 52m
3	Ethernet Overview, Layer 2 Switchports, Trunking, ISL, 802.1q, DTP	0h 47m
4	VTP, VTP Authentication, VTP Pruning	1h 02m
5	VTP Prune Eligible List, VTP Transparent, VTP Troubleshooting, Trunk Allowed List, Extended VLANs	0h 48m
6	VLAN and VTP Review	0h 19m
7	SVIs, Native Routed Interfaces, Router-on-a-Stick	0h 46m
8	Layer 2 EtherChannel, EtherChannel Load Balancing, Layer 3 EtherChannel	0h 57m
9	802.1q Tunneling, Layer 2 Protocol Tunneling, EtherChannel over 802.1q Tunneling	1h 03m
10	STP Root Bridge Election, STP Root Port Election, STP Designated Port Election, STP Priority, STP Cost, STP Port-Priority	1h 46m
11	STP Review	0h 12m
12	STP Timers, STP PortFast	0h 34m
13	STP UplinkFast	0h 11m
14	STP BackboneFast	0h 12m
15	STP BPDU Filter	0h 13m
16	STP BPDU Guard	0h 11m
17	STP Root Guard	0h 11m
18	STP Loop Guard, Unidirectional Link Detection (UDLD)	0h 11m
19	Multiple Spanning-Tree Protocol (MST)	0h 40m
20	Rapid Spanning-Tree Protocol (RSTP), Rapid-PVST	0h 18m
21	MST with Multiple Regions	0h 33m
22	Flex Links	0h 16m
23	Frame Relay	0h 39m
24	Frame Relay Configuration Part 1	0h 34m
25	Frame Relay Configuration Part 2	0h 41m
26	Frame Relay Switching	0h 27m
27	Back-to-Back Frame Relay	0h 08m
28	Frame-Relay End-to-End Keepalives	0h 18m
29	PPP, PPP PAP Authentication, PPP CHAP Authentication	0h 59m
30	PPPoFR, PPPoE	0h 40m
31	Transparent Bridging, IRB	0h 32m
32	Fallback Bridging	0h 14m
33	IP Routing Overview, Switching Paths, Static Routing	0h 42m
34	Static Routing Examples	0h 25m
35	IP Default-Gateway, IP Default-Network	0h 14m
36	On-Demand Routing (ODR)	0h 07m
37	Floating Static Routes	0h 10m
38	Backup Interface	0h 29m
39	Enhanced Object Tracking, IP SLA, Reliable Static Routing	0h 21m
40	Policy Routing	0h 43m
41	GRE Tunneling, GRE Recursive Routing Errors	0h 27m
42	Reliable Backup Interface with GRE	0h 25m
43	RIP Overview, RIP Versions, RIP Auto-Summary	0h 48m
44	RIP Split-Horizon, RIP Timers	0h 22m
45	RIP Broadcast Updates, IP Directed Broadcast, IP Broadcast-Address, Smurf Attacks, Fraggle Attacks	0h 16m
46	RIP Unicast Updates	0h 03m
47	RIP Offset-List	0h 18m
48	RIP Authentication	0h 11m
49	RIP Summarization	0h 10m
50	Prefix-Lists, RIP Distribute-List Filtering, RIP Administrative Distance Filtering	0h 48m
51	RIP Default Routing, RIP Conditional Default Routing	0h 18m
52	RIP Triggered, RIP Validate Update Source,	0h 12m
53	EIGRP Overview	0h 29m
54	EIGRP Auto-Summary	0h 07m
55	EIGRP Split-Horizon	0h 11m
56	EIGRP Update Types, EIGRP Neighbor, EIGRP Passive-Interface	0h 24m
57	EIGRP Hello-Interval, EIGRP Hold-Time	0h 05m
58	EIGRP Authentication	0h 11m
59	EIGRP Time Based Authentication	0h 25m
60	EIGRP Path Selection, EIGRP Metric Weights, EIGRP Traffic Engineering	0h 47m
61	EIGRP Unequal Cost Load Balancing, EIGRP Variance	0h 19m
62	EIGRP QUERY, EIGRP Summarization, EIGRP Leak-Map	0h 28m
63	EIGRP Stub Router Advertisement	0h 22m
64	EIGRP Default Routing	0h 13m
65	EIGRP Route Filtering	0h 11m
66	EIGRP Router-ID	0h 07m
67	Miscellaneous EIGRP Features	0h 02m
68	OSPF Overview	0h 27m
69	Establishing OSPF Adjacencies, Understanding the OSPF Database	0h 43m
70	OSPF Network Type Broadcast, OSPF DR/BDR Election, OSPF over NBMA, OSPF Network Type Non-Broadcast and Point-to-Multipoint	0h 56m
71	OSPF Network Type Point-to-Point, OSPF Network Type Mismatch	0h 13m
72	OSPF Network Type Point-to-Multipoint Non-Broadcast, OSPF Per Neighbor Cost	0h 17m
73	OSPF Network Type Loopback	0h 02m
74	OSPF Path Selection	0h 27m
75	OSPF Convergence Timers	0h 09m
76	OSPF Authentication	0h 12m
77	OSPF Summarization	0h 32m
78	OSPF Stub Areas, OSPF Totally Stubby Areas, OSPF NSSAs, OSPF Totally NSSAs	0h 40m
79	Controlling OSPF NSSA Redistribution	0h 02m
80	OSPF Type 7 to 5 Translator Election, OSPF LSA Type 3 Filter, OSPF Forwarding Address Suppression	0h 24m
81	Route Redistribution Overview	0h 36m
82	Route Redistribution Configuration & Verification, Connected Redistribution	0h 22m
83	OSPF External Path Selection, TCL PING Scripting	0h 33m
84	Routing Loops Overview, EIGRP Route Loop Prevention	0h 55m
85	Metric Based Routing Loops, Route Tagging	0h 46m
86	Administrative Distance Based Routing Loops, Debug IP Routing, IP Route Profile	0h 58m
87	BGP Overview, BGP Peering Types	0h 51m
88	Establishing BGP Peerings, EBGP Multihop, BGP Neighbor Disable Connected Check, BGP TTL Security	0h 49m
89	BGP 4-Byte ASNs	0h 20m
90	BGP Local AS, BGP Peer Groups	0h 30m
91	BGP Next-Hop Self, BGP Next-Hop Processing	0h 30m
92	BGP Route Reflectors	0h 37m
93	Large Scale BGP Route Reflectors with Clusters	0h 34m
94	BGP Confederation	0h 37m
95	BGP NLRI Advertisements, BGP Network Statement, BGP Redistribution	0h 43m
96	BGP Aggregation, BGP Aggregation & Summary-Only, BGP Aggregation & Unsuppress-Map	0h 46m
97	BGP Origin, BGP Aggregation & AS-Set, BGP Aggregation & Advertise-Map	0h 22m
98	BGP Conditional Route Injection	0h 21m
99	BGP Bestpath Selection, BGP Multipath, BGP Weight	0h 53m
100	BGP Local Preference, BGP Local Preference and Communities, BGP AS-Path Prepending,	0h 30m
101	BGP MED, BGP MED Missing As Worst, BGP Deterministic MED	0h 17m
102	BGP Communites, BGP Regular Expressions	0h 43m
103	BGP Filtering, BGP Convergence Timers, BGP Default Routing, Miscellaneous BGP Features	0h 24m
104	MPLS Overview, MPLS Label Distribution Protocol (LDP)	1h 05m
105	MPLS Tunnels, MPLS Penultimate Hop Popping (PHP)	0h 40m
106	MPLS Layer 3 VPNs Overview, VRF Lite	0h 36m
107	MPLS Layer 3 VPNs and VPNv4 BGP	1h 08m
108	MPLS Layer 3 VPN Verification & Troubleshooting	0h 49m
109	MPLS Layer 3 VPN OSPF PE-CE Routing Overview	0h 06m
110	MPLS Layer 3 VPN OSPF PE-CE Routing Path Selection & Sham-Links	2h 01m
111	MPLS Layer 3 VPN OSPF PE-CE Routing Loop Prevention & Down-Bit, OSPF Capability VRF-Lite	0h 40m
112	IPv6 Overview, IPv6 ICMPv6 ND, IPv6 over NBMA	0h 44m
113	IPv6 Routing Overview, IPv6 Static Routing	0h 28m
114	IPv6 RIPng	0h 20m
115	IPv6 EIGRPv6	0h 09m
116	IPv6 OSPFv3	0h 31m
117	MP-BGP for IPv6	0h 26m
118	IPv6 Tunneling	1h 13m
119	Multicast Overview, IGMP	0h 34m
120	PIM Overview	0h 18m
121	PIM Dense Mode	1h 03m
122	PIM Sparse Mode	0h 30m
123	PIM Sparse Mode Configuration	0h 36m
124	PIM Sparse Mode RPF & RP Troubleshooting	0h 27m
125	Auto-RP, Multicast over GRE Tunnels	0h 53m
126	Bootstrap Router (BSR), Bidirectional PIM, Source Specific Multicast (SSM)	0h 40m
127	MSDP, Anycast RP	0h 27m
128	IPv6 Multicast Routing	0h 24m
129	QoS Overview, IntServ QoS, DiffServ QoS, IP Precedence, DSCP, MQC, HQF	0h 41m
130	MQC Classification	0h 44m
131	FIFO, FQ, WFQ, CBWFQ, HQF	0h 50m
132	LLQ	0h 23m
133	WRED	0h 31m
134	Traffic Shaping, Traffic Policing	0h 40m
135	Frame Relay Traffic Shaping (FRTS)	0h 33m
136	RSVP	0h 07m
137	Catalyst 3560 QoS	1h 00m
138	IOS Security Overview, Access Lists (ACLs)	0h 58m
139	Time Based ACLs, Dynamic ACLs	0h 33m
140	Reflexive ACLs	0h 21m
141	TCP Intercept, Content Based Access Control (CBAC)	0h 34m
142	Zone Based Policy Firewall (ZBPF)	1h 09m
143	AAA, Local Authentication, Local Authorization, Role Based CLI Access	0h 43m
144	Port Security, Static CAM Entries, Storm Control, 802.1X Authentication, PACLs, RACLs, VLAN Access Maps (VACLs)	0h 48m
145	DHCP Snooping, Dynamic ARP Inspection (DAI), IP Source Guard	0h 12m
146	Protected Ports, Private VLANs	0h 25m
147	IP Services Overview, HSRP	1h 10m
148	VRRP, GLBP	0h 28m
149	NAT	0h 42m
150	DHCP, DNS	0h 30m
151	NetFlow	0h 09m
152	WCCP, Miscellaneous IP Services	0h 06m
153	System Management Overview, NTP, NTP Authentication	0h 24m
154	SNMP, RMON	0h 38m
155	Syslog, Telnet, SSH, Banners	0h 21m
156	EEM Scripting, Miscellaneous System Management	0h 26m
Total Duration		81h 42m

Slides - Diagrams

Slides - Introduction

Slides - Ethernet Switching

Slides - Advanced Ethernet Switching

Slides - Frame Relay

Slides - PPP

Slides - Transport Bridging

Slides - Redistribution

Slides - IOS Security

Slides - Layer 2 Security

Slides - IP Services

Slides - System Management

0:00:13	The next network type we have is point-to-multipoint non-broadcast,
0:00:18	which is identical in its operation to point-to-multipoint
0:00:22	with the one exception that we are sending our updates as unicasts as opposed to multicasts.
0:00:29	So, the non-broadcast and point-to-multipoint non-broadcast,
0:00:33	those are using unicast updates.
0:00:36	Broadcast, point-to-point, and point-to-multipoint are all using multicasts.
0:00:41	The multicast difference between them is that broadcast is usually two different addresses.
0:00:46	224.0.0.5 and 224.0.0.6
0:00:50	Where one of them is for the designated router. One of them is for all of the other routers.
0:00:55	The 225.0.0.6, that's for traffic going to the DR.
0:01:00	Point-to-point and point-to-multipoint, they're using just 224.0.0.5,
0:01:04	which is all OSPF routers.
0:01:08	Now, for point-to-multipoint non-broadcast, the case that we would want to use this
0:01:13	is that if we have a partial mesh of Layer 2 circuits
0:01:18	but the underlying netowrk is made up of different bandwidth values on the circuits.
0:01:23	The case that this is typical is that either in a frame-relay or ATM design
0:01:29	where we have router 5 connecting with different virtual circuits to the spokes.
0:01:36	But the virtual circuits are provisioned at different bandwidth levels.
0:01:40	So, let's say for example that router 5's physical interface here is a T1.
0:01:46	T1 is made up of 24 channels of DS0, which are 64 kilobits per second.
0:01:55	So, if we look at the effective bandwidth of this,
0:01:59	24 times 64 kilobits per second, it's 1,536 kilobits per second.
0:02:05	So, actual effective bandwidth value.
0:02:07	There's gonna be some other band signaling for this, which is the additional 8 kilobits per second.
0:02:15	That's not actual effective bandwidth.
0:02:17	So, sometimes when you see this listed as 1544, that's including the signaling.
0:02:25	but the actual useable bandwidth on the DS0 circuit is 64K.
0:02:29	So, let's say that this...
0:02:31	T1 interface, 1536 is broken down into 4 equal assignments.
0:02:39	So, each of this circuits assigned 384 kilobits per second.
0:02:47	So, 504 is 384K.
0:02:53	501, 503, and 502.
0:02:57	Okay, they're all the same bandwidth value.
0:02:59	In this case, it doesn't matter that when router 5 does it's calculation for the path selection
0:03:05	that it uses the single bandwidth value that is applied to the intreface level.
0:03:13	bewcause when we look at router 5's configuration,
0:03:16	if we Show Route Interface Serial 0/0/0,
0:03:22	all of this 4 circuits, they're assigned to the same interface.
0:03:27	This meaens if we Show IP OSPF Interface Serial 0/0/0,
0:03:32	all of these circuits are getting the same underlying cost value.
0:03:38	This is based on the interface's bandwidth value.
0:03:40	If I Show Interface Serial 0/0/0,
0:03:44	it says, "The bandwidth value is 1544."
0:03:48	But let's say that this is different. It's gonna represent the individual circuits.
0:03:52	If the bandwidth were 384 kilobits per second,
0:03:57	when we Show IP OSPF Interface Serial 0/0/0,
0:04:02	and let's just look at the cost,
0:04:05	it says now, "The cost is 260."
0:04:08	So, a 384 kilobit per second circuit by default results in a cost of 260.
0:04:15	But now, let's say that one of these links is not provisioned at that.
0:04:20	Maybe one of them is half of this. They're at 192.
0:04:24	And this link that's provisioned at 192, we'll say that this is router 2's circuit.
0:04:30	192 kilobits per second.
0:04:33	The problem now is that when router 5 looks at a route being learned from 2.
0:04:40	And a route being learned from 3.
0:04:43	They're both gonna get the underlying cost value that are applied to the same main interface.
0:04:51	So, in the case where the cost of the main interface does not reflect the underlying Layer 2 circuits,
0:04:58	that's what point-to-multipoint no-broadcast is for.
0:05:02	So, router 5 wwill still treat this as a collection of point-to-point links.
0:05:07	But we can apply on a per-neighbor basis what is the cost value
0:05:12	for link state updates that we are receiving for that neighbor.
0:05:15	So, now, let's look at what would happen if the bandwidth were 192.
0:05:20	We should see that there cost is gonna be doubled, it's 560.
0:05:25	So, at router 5's linklevel, I could say the IP OSPF network type is point-to-multipoint.
0:05:32	But the non-broadcast version.
0:05:35	Now, under the OSPF process, I could say that for the neighbor 150.42.0.1,
0:05:43	I wanna send unicast to them but I also wanna define their cost.
0:05:47	And theie cost will be 260.
0:05:51	Router 3 and 4, they likewise have the same identical cost.
0:05:59	But for router 2,
0:06:02	this cost is doubeld because the circuit speed is half. So, it's 520.
0:06:07	When we look at the end result to this and Show IP OSPF neighbors,
0:06:12	we see that we still have the adjacencies with all 4 of them.
0:06:16	If we look at the Debug IP Packet Detail,
0:06:20	we would see that the actual transport
0:06:23	of the packets between the neighbors are going to use the unicasts now.
0:06:29	No longer the multicast.
0:06:36	So, we see the unicast packets between the neighbors.
0:06:41	We can also see this is OSPF because it's protocol number 89.
0:06:47	If we look at the Show IP Route OSPF,
0:06:56	we'll see that there's a difference in the cost of the
0:07:00	routes to router 2 versus the other neighbors.
0:07:04	And I believe, let's see, let's look at the Show IP OSPF Interface Serial 0/0/0.
0:07:11	The timers here may be different.
0:07:16	Then the default ones. Let's go to the other side, let's see what the router 1 and 2 have.
0:07:21	Let's Show IP...
0:07:24	OSPF Interface S0/0.1
0:07:29	These are 30 and 120.
0:07:32	Let's see what router 3 has. Show IP OSPF Interface Serial 1/0.
0:07:41	This is 30 and 120.
0:07:42	So point-to-multipoint, point-to-multipoint non-broadcast, they both have the same timers, which is fine.
0:07:47	So, on router 5, let's look again at the...
0:07:52	Actually, what I'll do, let me shut the link down to router 4.
0:07:57	Because that is being preferred now based on the higher bandwidth there.
0:08:04	Now, let's Show IP Route OSPF.
0:08:11	We should see now that there's gonna be a difference in the cost,
0:08:15	between the loopback of router 3 and the loopback of router 2.
0:08:21	Because they're defined different cost values under the process.
0:08:27	Now, at the physical interface, I may need to remove the bandwidth statement here.
0:08:36	But if we look at the configuration under the process,
0:08:41	we see, we have the neighbor statements plus we have the cost value associated with them.
0:08:46	So, if I clear the routing table and then Show IP Route OSPF,
0:08:55	we should see that if we look at just those host routes,
0:09:06	the cost is gonna be different. I may need to clear the process now.
0:09:09	Let's say Clear IP OSPF Process.
0:09:31	So, it's showing 65 for all of these which means the interface cost is overriding this.
0:09:37	Let's say Show IP OSPF Interface Serial 0/0/0.
0:09:45	The cost of the link is 64.
0:09:49	I'm wondering if we need to set this higher. Let's say that...
0:09:53	the cost value is IP OSPF Cost...
0:10:03	we should see that the neighbor's cost is overriding what's on the interface.
0:10:12	So, what I may need to do here is also do this on the remote side, on the other spokes.
0:10:18	But if we look at the... Let's take a look at the documentation here. If we go to the main...
0:10:26	website - the main documentation's site,
0:10:28	this would be under products, IOS
0:10:32	Cisco IOS, 12.4, 12.4T
0:10:38	Then I want the configuration guide for OSPF and also the command reference.
0:10:43	So, on the reference guides, command reference,
0:10:49	under IP Routing, OSPF commands,
0:10:53	then let's say under...
0:10:59	neighbor OSPF...
0:11:14	It says, "To configure OSPF Routers interconnecting with non-broadcast networks,
0:11:17	chooes the neighbor command...
0:11:21	Optionally, assigns a cost to the neighbor in the integer 1 to 65535.
0:11:27	Neighbors with no specific cost configure will assume the cost of the interface
0:11:31	based on the IP OSPF cost command.
0:11:33	For point-to-multipoint interfaces, the cost keyword and the number arguement
0:11:38	are the only option that are applicable. The keyword does not apply to non-broadcast multiaccess networks.
0:11:43	Which would mean, the network type non-broadcast.
0:11:46	So, I'm wondering if the case that 5 has both commands under the routing process.
0:11:57	Let's see if I can remove the first one.
0:12:02	or actually, let's just start this over. Let's say "No router OSPF 1."
0:12:06	So, what I want is just the network statement.
0:12:13	And then theneighbor costs.
0:12:19	So, now, let's say, "Show Rune Section Router OSPF"
0:12:24	Now, it's showing what we just want.
0:12:25	So, I think it's because before we were using netowrk type non-broadcasts,
0:12:31	then I was entering the network command again or the neighbor command again.
0:12:36	So, most likely the first one was overriding it.
0:12:39	So, let's see what's the result in the routing table.
0:12:44	And then I will remove at the link level. So, no IP OSPF Cost.
0:13:33	So, this version may not actually support this then.
0:13:38	We should see a higher cost value that's beign received from 2's loopback as opposed to the other ones.
0:13:45	We could try this on the Ethernet to see whether it was supported then.
0:13:53	But this originally was supposed to be for the case where the PVC speeds are mismatching.
0:13:59	Let's try this one more thing, let's clear the OSPF process.
0:14:09	And see if that affects anything.
0:14:37	So, here, they're taking the cost of 64 form the link level instead of the process level.
0:14:43	Where you could also use this...
0:14:50	There's a question, "What is the network type on router 5's serial?"
0:14:52	It shold be point-to-multipoint non-broadcast.
0:14:58	Let's try it with this, let's set it just to...
0:15:09	Let's set it just to point-to-multipoint and not point-to-multipoint non-broadcast.
0:15:26	So, it's still taking the cost from the link level.
0:15:30	The other case where this would be useful is if the routers are connected over a LAN.
0:15:37	But the physical speeds of the Ethernets are different that are going to the switch.
0:15:44	So, let's say we have a Layer 2 switch in the middle here.
0:15:47	Router 1 is connecting with Fast Ethernet.
0:15:50	Router 3 is connecting with Fast Ethernet.
0:15:52	And router 1 is connecting with Regular Ethernet, so 10 megabits per second.
0:15:58	On router 2 and 3, if this was network-type broadcasts,
0:16:04	they would not be able to tell the difference between the 100 megabits per second connection and the 10.
0:16:14	So, we could change the network-type point-to-multipoint
0:16:18	and then specify on the per-neighbor basis, what the cost value is.
0:16:23	So, it may be that in the newer IOS, this is not supported for the frame-relay interfaces.
0:16:29	But this was the original usage for it.
0:16:31	That if you're PVC speeds are different, you could set the cost on a per-neighbor basis.
0:16:38	But again, the easier design solution for this is to never use a case like this on router 5 to begin with.
0:16:48	So, we'll see as we get into more details with the Layer 3 protocols.
0:16:52	The routing process, the muticast process, the QoS process.
0:16:56	A lot of things do not relate well to configurations
0:16:59	where the Layer 2 network does not map to the Layer 3 network on a one-to-one basis.
0:17:06	So, if router 5 had four separate point-to-point sub-interfaces,
0:17:11	then OSPF would be able to say,
0:17:13	"This subinterfaces have different cost value associated with than the other ones."
0:17:19	Then router 5 would be able to tell the difference between the PVC speeds.

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CCIE R&S Advanced Technologies Class v4.5
Title:	CCIE R&S Advanced Technologies Class v4.5
Duration:	81h 42m
The CCIE Routing & Switching Advanced Technologies Class is the first step in understanding CCIE level technologies and is a companion to the Advanced Technologies Lab Workbook. Each technology you need to know for the CCIE Routing & Switching lab will be described in detail using an instructor led hands on demonstration. The class consists of over 80 hours of in depth explanations and examples.
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