CCIE R&S Advanced Technologies Class v4.5

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

0:00:11	Before we get into our next topics we're going to spend a couple minutes to review
0:00:16	with spanning tree protocol and the root bridge election and then the path selection
0:00:21	and how we can modify those decisions.
0:00:26	So we saw yesterday
0:00:28	We essentially have a three step process that we need to go through when we are running spanning tree.
0:00:33	First we need to elect the root bridge that is going to be the reference point for the rest of the tree.
0:00:38	Again, this is done based on the bridge ID
0:00:41	that contains the priority, the system ID extension, and then the MAC address of the device.
0:00:47	The lowest bridge ID is going to be preferred
0:00:50	so if there is a tie in the priority, then we essentially look at whatever device has the lowest MAC address.
0:00:56	When we are changing the priority a lower numerical value is going to be better
0:01:01	and we have to change it in increments of 4096.
0:01:04	So if we say spanning tree VLAN one priority one
0:01:09	the command line is just going to spit back an error message
0:01:11	and then tell us what are the proper values that we can actually configure.
0:01:16	So if we were to look at switch one and try this out
0:01:19	if we say spanning tree VLAN one priority one
0:01:26	it says these are the valid values - it has to be in increments of 4096.
0:01:31	Now the reason we have this is that the newer specification of spanning tree has to take into account
0:01:37	the system ID extension,
0:01:40	which again essentially is the VLAN number
0:01:43	or in the case of today when we're looking at multiple spanning tree
0:01:47	it's going to be the MST instance number.
0:01:50	So the priority value plus the system ID extension
0:01:53	ensure that we have a unique bridge ID on a per spanning tree instance basis.
0:01:59	So even though we are reusing the same MAC address over and over
0:02:03	since the VLAN number is always unique to begin with
0:02:06	we end up in a unique bridge ID.
0:02:11	So once we elect the root bridge
0:02:13	we could look at the show spanning tree for a particular VLAN
0:02:16	or we could look at the show spanning tree root
0:02:19	which is going to show us quickly what is the root bridge ID
0:02:22	for every single instance of spanning tree that we're running.
0:02:26	So on switch one if we look at the show spanning tree root
0:02:31	in this case we have VLAN one and then VLAN 10, 20, 30, 40, up through 100.
0:02:37	We can see that the root bridge is the same for every particular instance.
0:02:43	So whoever has this particular MAC address
0:02:46	had a default priority of 32768
0:02:50	because if we add the VLAN number 232768
0:02:57	we could see that's what the priority value is.
0:02:59	So VLAN ten is 32768 plus the system ID extension of ten.
0:03:05	Our end to end cost to get there is 31.
0:03:09	Then we can also see the timers that that particular root bridge is advertising.
0:03:14	So we'll see when we modify the timers here
0:03:17	the value that the root bridge has configured is the value that the rest of the network is going to be using.
0:03:24	So setting the timers locally doesn't affect anything.
0:03:30	Okay, there's a question - why does the bridge ID have to be different between the VLANs?
0:03:37	Because when we receive the BPDUs
0:03:40	that's how the router is identifying what particular VLAN instance that BPDU is relating to.
0:03:49	So inside the bridge ID it's basically telling us what particular of instance of spanning tree that packet is related to.
0:03:58	So previously, before we had the system ID extension, we had to use a separate MAC address
0:04:04	per instance but now we can see that the MAC address field can be the same
0:04:09	as long as the addition of the priority and the MAC address is going to give us a unique identifier.
0:04:21	Okay, then we saw that we can change the ports role
0:04:25	which would affect either the root port election or the designated port election
0:04:30	where the root port is essentially the interface that has the lowest total cost value in order to reach the root bridge.
0:04:38	So if we look at all of the BPDUs that we are receiving in
0:04:42	where the BPDU is the bridge protocol data unit
0:04:45	basically just means a spanning tree packet.
0:04:47	So if we look at all the spanning tree packets coming in
0:04:50	if we look at what's the total cost of what's coming in plus our local link costs.
0:04:56	So if my link cost is one and I'm receiving a BPDU that says it has a cost of ten
0:05:02	it means that my total root path cost would be eleven if I were to use that link.
0:05:08	So it's a pretty simple algorithm. You're just adding the cost on a hop by hop basis.
0:05:12	So if we look at whatever is the lowest end to end cost
0:05:14	that interface is going to be used as the root port.
0:05:18	If for some reason multiple interfaces have the same total cost value
0:05:23	then we go down to the lowest upstream bridge ID
0:05:27	for the tie breaker or if that is still the same we go to the lowest upstream port ID.
0:05:35	Now again, the very last decision, which is the port identifier
0:05:40	this is only used if the upstream bridge ID is the same
0:05:44	which means essentially that you would have two links to the same upstream switch.
0:05:50	So if there's two links between switch one and switch two
0:05:53	which ever is the downstream switch
0:05:55	would essentially be making the decision based on the upstream switch's port identifier.
0:06:01	Which again, the port identifier is made up of two fields - it's the port number that the switch is generating locally,
0:06:08	kind of like an SNMP interface index number,
0:06:12	and then the port priority value which will be 128 by default.
0:06:18	So to change this selection of either the root port or the designated port
0:06:25	usually the easiest way to do this is just to modify the path's cost.
0:06:29	We can do this by directly changing the cost at the interface with the spanning tree cost command
0:06:34	or the spanning tree VLAN cost
0:06:36	or we could change the bandwidth on the interface which then implicitly changes the cost value.
0:06:44	If for some reason we don't want to use the cost directly to modify the path selection
0:06:50	we could lower our bridge ID by changing the priority
0:06:55	because when we're looking at either the interface to use as the root port or what interface would become the designated port
0:07:01	whichever device has the higher, excuse me, the lower bridge ID
0:07:07	that would be the one that is preferred.
0:07:10	Then our last case we could change the port priority but again that's only if you have multiple links between the same two switches.
0:07:19	So when we're verifying this, you need to make sure that you are looking at the show spanning tree detail
0:07:26	or the show spanning tree VLAN detail
0:07:29	because that will show us not only our local interfaces
0:07:33	but all of the information that we are receiving in from the upstream bridges.
0:07:41	So if we look at this on switch one
0:07:43	and let's say that we're talking about just VLAN one.
0:07:46	We'll say show spanning tree VLAN one.
0:07:52	It says that there's three interfaces we are running this instance on.
0:07:59	It's FastEthernet three.
0:08:05	Thirteen and sixteen.
0:08:09	Okay, FastEthernet three is going down to one of the end hosts so that is not going to be part of the path selection.
0:08:18	So basically we need to choose between these two interfaces - between thirteen and sixteen.
0:08:23	Now with this output
0:08:25	we don't know what the total end to end cost is on these links. We only know that the local interface cost is nineteen.
0:08:33	Also, the local interface port ID is made up of the priority 128 and then the numbers 15 and 18 respectively.
0:08:42	So we can see this port number, it doesn't always correspond directly to the interface number
0:08:47	and if you have any platform that uses multiple modules or multiple line cards
0:08:52	like stackable 3700s or 4500 or 6500
0:08:57	then when you have the multiple slot values like FA2/5
0:09:02	then the port number is just going to be something random that the switch is generating internally.
0:09:08	So to figure out really what's going on
0:09:11	with this selection, we would need to look at the show spanning tree VLAN one detail.
0:09:19	Switch one says that there's these two links that we could possible use.
0:09:22	One of them is blocking; one of them is forwarding.
0:09:26	So now we need to figure out why are we choosing the second interface as the root port as opposed to the first one.
0:09:35	First thing we would look at is what is the total end to end cost.
0:09:39	For both of these interfaces my local cost is 19.
0:09:44	The upstream devices have a cost of 19 and zero.
0:09:50	So it means that if I were to use the second interface, my total cost is 19.
0:09:56	If I were to use the first interface, the total cost is going to be 38.
0:10:01	So we're choosing the link with the lower cost of 19.
0:10:04	That's going to be the root port and the closest interface from the end to end cost perspective.
0:10:13	So if we wanted to
0:10:18	Oh, I'm sorry. You're right. It's not...I'm looking at the wrong field there.
0:10:23	The designated path cost there is 12.
0:10:26	Okay, so it's 12 plus 19.
0:10:29	So we have 31 here versus 38.
0:10:35	So in either case the second interface is still
0:10:38	closer but we're adding basically the designated path cost
0:10:42	that means that is the cost
0:10:45	of the switch that has the designated port.
0:10:50	So if we were to look at this from the diagrams perspective
0:10:54	and we look at
0:10:59	switch one
0:11:03	It says that our root port
0:11:08	was which of these interfaces? The root port was FastEthernet 16.
0:11:14	So this is the root port. This one is blocking.
0:11:19	If our port is blocking it means that on the other side that should be the designated port.
0:11:27	Likewise on the other side of our root port, that's going to be the designated port
0:11:31	because designated is facing downstream.
0:11:34	So when switch one is looking at it's local interface FastEthernet 16 with a cost of 19,
0:11:41	plus the designated cost of 12,
0:11:45	that's what switch three is using as it's cost to reach the root.
0:11:51	So it's essentially like a local cost and an advertised cost.
0:11:56	Then between switch one and switch two
0:11:58	switch one is saying my local interface has a cost of 19
0:12:02	and that I am learning from the designated port also a cost of 19
0:12:06	so both of those together would be 38.
0:12:09	So we're simply going to choose the lower one which is 31 versus the 38.

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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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