|
0:00:12
|
Welcome everybody to Internetwork Experts
|
|
0:00:14
|
CCIE Routing and Switching Advanced Technologies class.
|
|
0:00:18
|
I am Brian McGahan and I will be your instructor for the week.
|
|
0:00:22
|
Now ultimately the goal for this class is to understand a structured approach
|
|
0:00:28
|
for configuring and for verifying and troubleshooting
|
|
0:00:32
|
all of the topics that are within the scope
|
|
0:00:34
|
of the CCIE Routing and Switching Lab blueprint.
|
|
0:00:37
|
So essentially everything within the blueprint
|
|
0:00:38
|
is going to be fair game for this class.
|
|
0:00:40
|
We're going to be covering a lot of these topics
|
|
0:00:42
|
in very, very fine details.
|
|
0:00:45
|
The vast majority of the time I'm going to be spending
|
|
0:00:47
|
or showing the screen sharing with my command line
|
|
0:00:52
|
actually live on the routers going through different configuration examples
|
|
0:00:55
|
and then just as important,
|
|
0:00:57
|
what are the different show commands we can use
|
|
0:00:59
|
what are the different debug commands we can use
|
|
0:01:01
|
to actually check to make sure the configurations are working
|
|
0:01:05
|
then, if they're not working,
|
|
0:01:07
|
what is the step-by-step procedure we can go through for troubleshooting these?
|
|
0:01:11
|
Now, ideally up to this point,
|
|
0:01:13
|
everyone has a pretty good basic or intermediate understanding
|
|
0:01:17
|
of all of the Layer 2 and Layer 3 topics
|
|
0:01:21
|
that are within the scope of the lab exam.
|
|
0:01:23
|
Layer 2 technologies like Ethernet and frame relay,
|
|
0:01:25
|
Layer 3 routing with the IGPs, with BGP, Multicast, and MPLS
|
|
0:01:31
|
and then miscellaneous features in the IOS
|
|
0:01:33
|
like quality of service, security features, and management.
|
|
0:01:37
|
Now, the actual official topic list for CCIE Routing and Switching,
|
|
0:01:42
|
you can get it if you go to cisco.com/go/ccie
|
|
0:01:46
|
and if we take a look at this right now
|
|
0:01:50
|
if you start at the main CCIE webpage
|
|
0:01:55
|
then go down to Routing and Switching
|
|
0:02:01
|
then on the right we have the lab topics
|
|
0:02:05
|
lab exam topics version 4
|
|
0:02:08
|
then we want to see the topics for the lab exam.
|
|
0:02:13
|
So let me log in here.
|
|
0:02:27
|
So here is the official list that is current for the version 4 blueprint.
|
|
0:02:33
|
Now, in general, this blueprint is going to be a pretty good representation
|
|
0:02:39
|
of what the topics are going to be covered on the lab exam.
|
|
0:02:43
|
But you can see from the first paragraph here
|
|
0:02:45
|
it says that these topics are a general guideline
|
|
0:02:47
|
for content likely to be included.
|
|
0:02:49
|
However, other related topics may also appear
|
|
0:02:51
|
on a specific delivery of the exam.
|
|
0:02:54
|
So, generally they're saying this is the vast majority of the content
|
|
0:02:58
|
but we're giving ourselves an out if we happen to cover something
|
|
0:03:02
|
that is not explicitly on this list that's technically still fair game.
|
|
0:03:06
|
Now, since we're talking about the Routing and Switching exam,
|
|
0:03:09
|
we can assume that some topics definitely will not be included,
|
|
0:03:13
|
things like IPSEC, VPNs that would be for the CCI security track,
|
|
0:03:20
|
or things like Call Manager Express that would be for the CCI Voice Track.
|
|
0:03:26
|
But for Routing and Switching,
|
|
0:03:27
|
generally we're going to be covering anything that is related to the enterprise.
|
|
0:03:32
|
So all of the Layer 2 technologies we can see here
|
|
0:03:35
|
things like spanning tree, both in Per-VLAN spanning tree,
|
|
0:03:40
|
common spanning tree, multiple spanning tree, rapid spanning tree,
|
|
0:03:44
|
VLANs, VTP, trunking, EtherChannel, all of the core topics
|
|
0:03:49
|
that are inherent to Layer 2 Ethernet switching.
|
|
0:03:53
|
Then we see some other variations like PPP over Ethernet,
|
|
0:03:56
|
RSPAN, SPAN, but we see that there's a lot of things
|
|
0:04:01
|
that aren't specifically listed here for switching.
|
|
0:04:04
|
Let's say like 802.1Q tunneling or private VLANs or port security,
|
|
0:04:11
|
so generally those things will still be within the scope of the blueprint
|
|
0:04:15
|
it's just that they're not listed individually on this particular
|
|
0:04:19
|
topic list that they're showing.
|
|
0:04:22
|
Then for other Layer 2 topics we have frame relay,
|
|
0:04:26
|
HDLC and PPP, so basically anything that is not really hardware specific
|
|
0:04:31
|
that relates to Layer 2.
|
|
0:04:33
|
So for example you should not see
|
|
0:04:36
|
configuring a channelized DS3 interface
|
|
0:04:39
|
in the Routing and Switching exam.
|
|
0:04:40
|
You may see the Layer 2 version of that
|
|
0:04:44
|
which is going to be Frame Relay or PPP running over a serial link
|
|
0:04:48
|
but they're not really going to be testing on
|
|
0:04:51
|
the very specific hardware topics
|
|
0:04:53
|
because a lot of that is different
|
|
0:04:56
|
depending on which particular hardware platform that we're dealing with.
|
|
0:04:59
|
So as you're going through you preparation for the exam
|
|
0:05:03
|
a lot of the times it doesn't really matter what particular hardware platform you're using
|
|
0:05:08
|
as long as you can run the particular software release that the exam is using
|
|
0:05:13
|
which in the case currently is 12.4T Advanced Enterprises Services
|
|
0:05:18
|
and then 12.2 Advanced IP Services for the catalyst switches.
|
|
0:05:23
|
So whether you're doing this on a 2600s or 3600s, 1800s, 2800s,
|
|
0:05:30
|
as long as you have that particular version and feature set support
|
|
0:05:34
|
then implementing frame relay or implementing PPP over Ethernet
|
|
0:05:39
|
is going to be the same between the two different platforms.
|
|
0:05:43
|
So since we're not testing on hardware specific topics
|
|
0:05:47
|
it really doesn't matter the particular hardware that we're using.
|
|
0:05:51
|
This also means that for Routing and Switching
|
|
0:05:53
|
the vast majority of topics could also be tested
|
|
0:05:56
|
in Dynamips or GNS3 as long as you use a virtual router
|
|
0:06:02
|
that's running that particular software version
|
|
0:06:04
|
which again is 12.4T Advanced Enterprise Services.
|
|
0:06:08
|
So as we move on through the blueprint
|
|
0:06:12
|
beyond Layer 2 we have our Layer 3 technologies for IP version 4.
|
|
0:06:17
|
So basically any IGP, BGP, or feature of IP version 4
|
|
0:06:23
|
is going to be within the scope of the Routing and Switching exam.
|
|
0:06:27
|
So you'll see likewise it's not going to list
|
|
0:06:29
|
every single topic under OSPF
|
|
0:06:32
|
or every single topic under EIGRP but just because it doesn't say
|
|
0:06:38
|
Type 3 LSA filtering for OSPF version 2
|
|
0:06:41
|
it doesn't mean that that is not within the scope of the exam.
|
|
0:06:45
|
So as we get into more of the details of the individual technologies
|
|
0:06:49
|
we're essentially going to be covering every possible topic
|
|
0:06:53
|
for Layer 2, Layer 3, and the services
|
|
0:06:56
|
that is going to be within the scope of this exam.
|
|
0:06:59
|
Well, I shouldn't say really every single topic
|
|
0:07:01
|
probably 95% or more of the topics that are going to be within the scope of the exam.
|
|
0:07:07
|
Now, as we get to the individual technology areas,
|
|
0:07:11
|
if there is something that I'm not covering in particular
|
|
0:07:14
|
that you have questions on
|
|
0:07:15
|
feel free to ask me that.
|
|
0:07:17
|
You'll see that this class format is very free form.
|
|
0:07:21
|
I don't have a very strict schedule that I'm going to be sticking to.
|
|
0:07:25
|
So basically however long it takes for us to cover these topics
|
|
0:07:28
|
that's how long the class is going to be.
|
|
0:07:33
|
So moving on beyond IP version 4
|
|
0:07:36
|
we see that IP version 6 is listed here.
|
|
0:07:40
|
Notice here it doesn't say static routing for IPv6
|
|
0:07:44
|
or RIP NP for IPv6.
|
|
0:07:46
|
But I would assume that these topics are going to be within the scope.
|
|
0:07:51
|
Now the next one 4.00, Implementing MPLS Layer 3 VPNs,
|
|
0:07:57
|
this is one of those scary topic areas for a lot of people
|
|
0:08:01
|
since MPLS is fairly new to the Routing and Switching exam
|
|
0:08:05
|
and in the enterprise a lot of people don't have deployment experience with it.
|
|
0:08:10
|
We are going to spend a significant amount of time on this particular topic
|
|
0:08:14
|
talking about the Layer 3 VPNs using the VRFs,
|
|
0:08:20
|
using Multi-VRF or VRF-Lite,
|
|
0:08:23
|
and then how all of the IGPs and BGP interact with the MPLS environment.
|
|
0:08:29
|
So we'll go over all the different variations
|
|
0:08:32
|
of how do we run OSPF with the MPLS cloud,
|
|
0:08:35
|
how do we run IEGRP, VGP, etc.
|
|
0:08:42
|
Then we have multicast here,
|
|
0:08:45
|
network security, things like access lists, zone based firewall,
|
|
0:08:49
|
content based access control.
|
|
0:08:51
|
So the only thing that would not be in the scope of network security
|
|
0:08:55
|
is going to be any type of IP SEC or SSL VPN implementations.
|
|
0:09:01
|
So that's going to be reserved for the CCI Security exam.
|
|
0:09:06
|
But anything else that's related to the IOS,
|
|
0:09:08
|
securing the control plane, and securing the data plane
|
|
0:09:12
|
with the different types of firewall implementations,
|
|
0:09:14
|
we are going to be covering that in detail the third week of class
|
|
0:09:18
|
as we get into the miscellaneous services.
|
|
0:09:24
|
Then number seven, we have implementing network services,
|
|
0:09:27
|
things like the first hop redundancy protocols, HSRP,
|
|
0:09:30
|
VRRP and GLBP, network time, DHCP, WCCP.
|
|
0:09:36
|
Now this is a very large topic domain, the network services,
|
|
0:09:40
|
and as you can see they're not listing everything here explicitly.
|
|
0:09:44
|
So things like DNS server or DNS client,
|
|
0:09:48
|
even though it's not listed in this topic domain,
|
|
0:09:51
|
I would assume that it's part of that scope.
|
|
0:09:54
|
So a lot of these type of topics,
|
|
0:09:56
|
there's not a lot of technology understanding that goes behind them.
|
|
0:10:01
|
So I would assume at this point everyone knows what DHCP is
|
|
0:10:04
|
or what network time is.
|
|
0:10:06
|
A lot of these when you are dealing with them
|
|
0:10:08
|
in the scope of the Routing and Switching exam,
|
|
0:10:11
|
it's just understanding where this topic is located on the documentation
|
|
0:10:15
|
and how to take the configuration examples that Cisco has
|
|
0:10:19
|
and then apply it to that particular scenario.
|
|
0:10:22
|
So for Routing and Switching CCIE,
|
|
0:10:24
|
they're not assuming that you're going to be an expert in DHCP
|
|
0:10:27
|
or an expert in network time.
|
|
0:10:33
|
Next, section 8, quality of service.
|
|
0:10:36
|
This is definitely very important,
|
|
0:10:38
|
especially when we're talking about the dealing with these technologies in the enterprise,
|
|
0:10:43
|
so we'll spend pretty much a full day or more talking about QoS
|
|
0:10:48
|
when we get to the third week of class
|
|
0:10:51
|
and this is going to include both Layer 2 QoS
|
|
0:10:54
|
on the Catalyst IOS
|
|
0:10:57
|
and the Layer 3 QoS on the regular routers IOS.
|
|
0:11:02
|
Now notice here that it doesn't say implementing the legacy QoS mechanisms
|
|
0:11:08
|
so it says implement QoS with the modular quality of service command line interface.
|
|
0:11:13
|
I would assume thought that you should still have a general understanding
|
|
0:11:19
|
about how the legacy QoS mechanisms work.
|
|
0:11:23
|
Now most of the time when you're implementing these in production
|
|
0:11:27
|
you would want to choose the MQC based variations of them
|
|
0:11:31
|
but it doesn't hurt to understand where these evolved from.
|
|
0:11:39
|
Then sections 9 and 10 we have troubleshooting
|
|
0:11:41
|
and optimizing the network
|
|
0:11:43
|
so hopefully as everybody knows
|
|
0:11:45
|
the current CCI Routing and Switching lab exam format
|
|
0:11:49
|
is broken down into two discrete steps.
|
|
0:11:53
|
First we have a two hour troubleshooting section
|
|
0:11:57
|
followed by a six hour configuration section.
|
|
0:12:01
|
So for all of the topics that we go through
|
|
0:12:03
|
in Ethernet, frame relay, IGP, BGP, and beyond,
|
|
0:12:08
|
we are going to be talking about not only the configuration
|
|
0:12:12
|
but all of the detailed troubleshooting steps we would need to go through
|
|
0:12:15
|
if there was a problem with this particular technology.
|
|
0:12:19
|
So some of these we'll spend more time on than others.
|
|
0:12:23
|
Things like MPLS and multicast and some of the IGPs and BGP
|
|
0:12:30
|
where typically most of the troubleshooting would be involved.
|
|
0:12:34
|
We will spend a lot of time going through the different debugs,
|
|
0:12:36
|
going through the different show commands,
|
|
0:12:38
|
and looking at this step by step.
|
|
0:12:41
|
What's a structured approach that we could apply
|
|
0:12:45
|
onto troubleshooting this particular technology
|
|
0:12:48
|
as it applies to the CCIE lab exam?
|
|
0:12:55
|
Then we see last but not least optimizing the network;
|
|
0:12:58
|
things like NetFlow, RMON, the Embedded Event Manager,
|
|
0:13:01
|
so anything that could be used to monitor the IOS
|
|
0:13:05
|
whether we're talking about the routers or the Layer 2 switches.
|
|
0:13:08
|
That stuff is going to be within the scope of the exam.
|
|
0:13:12
|
Now I would not assume that things like the Embedded Event Manager,
|
|
0:13:16
|
they're not going to want you to be an expert in TCL scripting
|
|
0:13:21
|
or EEM scripting
|
|
0:13:23
|
so something like this, as long as you know where it's located on the documentation
|
|
0:13:27
|
and you've tried it out a couple of times on the command line
|
|
0:13:30
|
as we will in the third week of class
|
|
0:13:33
|
then I would just check this off the list and move on.
|
|
0:13:36
|
The same thing would be true of implementing FTP or TFTP
|
|
0:13:41
|
so there's really not a lot of technology understanding
|
|
0:13:43
|
behind setting up the router as an FTP server
|
|
0:13:47
|
or a TFTP server for its IOS image or for its configuration images
|
|
0:13:52
|
so we're not going to be spending as much time on these topics
|
|
0:13:55
|
as we will something that's really the core of the technologies
|
|
0:13:59
|
like VGP or OSPF version 2.
|
|
0:14:04
|
So these types of topics under optimizing the network
|
|
0:14:07
|
that's what we will be talking about the third week of class
|
|
0:14:11
|
which is all of the miscellaneous things.
|
|
0:14:15
|
Now the only issue with the official blueprint that we looked at there
|
|
0:14:19
|
there's a lot of line items that are not listed
|
|
0:14:22
|
in the blueprint.
|
|
0:14:24
|
So like I said, just because RIP NG is not listed under IPv6
|
|
0:14:28
|
doesn't mean that you can just skip over that in your preparation.
|
|
0:14:32
|
So we have on our CCI blog,
|
|
0:14:36
|
a post that is called the Expanded Study Blueprint
|
|
0:14:39
|
that is a more detailed list of what the blueprint really should be
|
|
0:14:44
|
and basically what you can use as kind of a checklist
|
|
0:14:48
|
as you're going through your preparation
|
|
0:14:50
|
to make sure that you have covered that particular topic.
|
|
0:14:53
|
So if you search for the expanded blueprint
|
|
0:15:06
|
we could see under implementing Layer 2 technologies
|
|
0:15:10
|
it lists not only what they did in the blueprint
|
|
0:15:12
|
which is things like rapid spanning tree, multiple spanning tree,
|
|
0:15:15
|
but also more of the details of advanced spanning tree features
|
|
0:15:19
|
like Loop guard, Root guard, BPDU guard,
|
|
0:15:23
|
PortFast, UplinkFast, BackboneFast,
|
|
0:15:25
|
so this type of stuff we will be talking about this week
|
|
0:15:29
|
within the scope of the Layer 2 technologies
|
|
0:15:32
|
but what's good about this list
|
|
0:15:35
|
is that you could print this out or save this
|
|
0:15:38
|
and basically use this as a line by line checklist
|
|
0:15:41
|
to make sure that you have covered this topic
|
|
0:15:43
|
before you actually get to the lab exam.
|
|
0:15:47
|
So just because it doesn't say Root guard in the official blueprint
|
|
0:15:51
|
doesn't mean that you can skip over this in your preparation.
|
|
0:15:55
|
So again you can get that if you go to blog.ine.com
|
|
0:15:58
|
and search for expanded study blueprint
|
|
0:16:01
|
or you could just Google site:blog.ine.com expanded blueprint.
|
|
0:16:07
|
Now the hardware topology that I'm going to be using for this class
|
|
0:16:11
|
is the same that is used in all of our routing and switching products.
|
|
0:16:15
|
So whether it's the Volume 1 or Volume 2 workbook,
|
|
0:16:18
|
it is all going to include six routers
|
|
0:16:20
|
that are running 12.4T Advanced Enterprise Services
|
|
0:16:24
|
and four switches that are running the Catalyst IOS 12.2 Advanced IP Services.
|
|
0:16:30
|
Now like I mentioned, if you're trying to replicate this
|
|
0:16:32
|
through your home lab or you have a lab at your office
|
|
0:16:35
|
you don't necessarily need to follow the exact platforms
|
|
0:16:39
|
that we are using or that they're using in the actual lab exam
|
|
0:16:44
|
as long as you have support for this particular version.
|
|
0:16:48
|
So if you have a 3800 or you have an 1800
|
|
0:16:51
|
they're essentially going to have the same features
|
|
0:16:53
|
the main difference is that the 3800
|
|
0:16:55
|
is going to be able to forward packets faster than the 1800.
|
|
0:17:00
|
Within the scope of just lab study we don't really care
|
|
0:17:03
|
what the packet per second capability of the platform is.
|
|
0:17:08
|
Now also there will be some miscellaneous devices
|
|
0:17:10
|
like the access server, the frame relay switch,
|
|
0:17:13
|
and the backbone routers to inject some routes into the topology
|
|
0:17:18
|
so these, within the lab exam, you don't need to worry about these.
|
|
0:17:22
|
You're not going to be touching these for the configurations section,
|
|
0:17:27
|
but within the troubleshooting section
|
|
0:17:29
|
essentially anything that is shown in that diagram
|
|
0:17:33
|
could potentially be used for troubleshooting.
|
|
0:17:37
|
Now as the very last section of this class,
|
|
0:17:40
|
after we wrap up all the Layer 2,
|
|
0:17:42
|
all the Layer 3, and all the miscellaneous topics,
|
|
0:17:45
|
we'll talk about lab strategy -
|
|
0:17:47
|
how to approach the troubleshooting section,
|
|
0:17:49
|
how to approach the configuration section,
|
|
0:17:52
|
and then we'll go into more details about these type of topics.
|
|
0:17:58
|
Now the actually topology that I'm using
|
|
0:18:00
|
if you go to this link here - ine.com/rack-rentals
|
|
0:18:06
|
you'll find a link to the hardware topology PDF
|
|
0:18:12
|
and in here this is going to list what the physical cabling is
|
|
0:18:15
|
for the topology I'm using.
|
|
0:18:18
|
So here it's showing the serial links
|
|
0:18:20
|
that are going to be used for frame relay
|
|
0:18:22
|
and for the back to back links
|
|
0:18:24
|
then also for the Ethernet switching.
|
|
0:18:27
|
You can see the four switches, switch 1 through switch 4,
|
|
0:18:31
|
they each have three links going to all of the other three switches.
|
|
0:18:37
|
So for today's class, as we're covering mainly Layer 2 Ethernet switching,
|
|
0:18:43
|
we're going to be dealing with just switch 1 through switch 4
|
|
0:18:47
|
and then using the routers just for some basic testing
|
|
0:18:50
|
for direct Layer 2 connectivity.
|
|
0:18:53
|
So we're really not going to get into details of the routers
|
|
0:18:55
|
until we get into frame relay,
|
|
0:18:58
|
to things like PPP over Ethernet, PPP over frame relay,
|
|
0:19:01
|
and then the next week of class
|
|
0:19:05
|
when we get into the Layer 3 routing topics.
|
|
0:19:13
|
So also in this document, if you go down to the next page
|
|
0:19:15
|
you can see a table that lists
|
|
0:19:19
|
what are the particular connections for the routers.
|
|
0:19:22
|
So, for example, router 1's Fast Ethernet 0/0 interface
|
|
0:19:27
|
connect to switch 1's port Fast Ethernet 0/1.
|
|
0:19:31
|
This is going to be important to understand what is the physical topology
|
|
0:19:37
|
versus the logical topology that I'm going to be showing in a lot of the diagrams.
|
|
0:19:41
|
So you may want to print this out as a reference
|
|
0:19:44
|
to make sure you understand
|
|
0:19:46
|
what the particular topology examples I'm using are.
|
|
0:19:50
|
So before we get into our technical topics for Layer 2 switching
|
|
0:19:55
|
I want to spend some time talking about general preparation strategy
|
|
0:19:59
|
for CCI Routing and Switching
|
|
0:20:01
|
and what are some of the different resources
|
|
0:20:03
|
that you have available to you
|
|
0:20:05
|
as you're trying to learn these topics
|
|
0:20:07
|
and ultimately take and pass the CCIE Routing and Switching Lab exam.
|
|
0:20:14
|
Now personally, myself along with Brian Dennis and Peter,
|
|
0:20:19
|
I have been doing this for about 10 years now, CCIE training,
|
|
0:20:24
|
and Brian Dennis has been doing it almost 15 years now,
|
|
0:20:27
|
and we've seen a lot of different candidates over the years
|
|
0:20:31
|
and seen what has been a successful methodology
|
|
0:20:35
|
for preparing for and passing the lab exam
|
|
0:20:37
|
and many unsuccessful preparation strategies.
|
|
0:20:43
|
Now really the key behind passing this exam
|
|
0:20:45
|
is a very, very simple logic
|
|
0:20:48
|
but when we get into the details of actually applying it
|
|
0:20:51
|
it becomes pretty complex.
|
|
0:20:54
|
The fact of the matter is
|
|
0:20:56
|
that if you learn how the technologies work
|
|
0:20:59
|
from a fundamental level
|
|
0:21:01
|
it doesn't matter what questions they ask you in the exam
|
|
0:21:04
|
you should be able to reason through
|
|
0:21:06
|
what is the question asking me in the first place
|
|
0:21:09
|
and what's the step by step process I need to do
|
|
0:21:11
|
in order to solve this particular question.
|
|
0:21:15
|
So they key of the lab exam
|
|
0:21:17
|
is that the vast majority of it,
|
|
0:21:19
|
probably 80% +,
|
|
0:21:21
|
is really foundational understanding about how the different Layer 2,
|
|
0:21:25
|
Layer 3, and miscellaneous topics work.
|
|
0:21:30
|
So if you understand at a fundamental level
|
|
0:21:32
|
how OSPF works, how the adjacency state machine works,
|
|
0:21:37
|
how the path selection state machine works,
|
|
0:21:39
|
then there should be no particular question they could ask you
|
|
0:21:42
|
related to OSBF that you should not know off the top of your head
|
|
0:21:48
|
or know where you need to go in the documentation
|
|
0:21:51
|
in order to use either the configuration guide
|
|
0:21:54
|
or the command reference to figure out
|
|
0:21:56
|
what's the implementation I need to do
|
|
0:21:58
|
in order to solve this.
|
|
0:22:01
|
Now the problem historically we've seen with this exam
|
|
0:22:04
|
is that a lot of people try to go
|
|
0:22:07
|
above and beyond what's really necessary
|
|
0:22:10
|
and try to learn just these tips and tricks
|
|
0:22:13
|
or "gotchas" of the lab exam
|
|
0:22:16
|
where really if you learn just these topics
|
|
0:22:20
|
then you'll see that there's a lot of holes
|
|
0:22:22
|
in your knowledge base
|
|
0:22:25
|
so you essentially end up in a case where
|
|
0:22:28
|
they're asking you questions in the exam
|
|
0:22:30
|
that you either don't understand what they're asking you
|
|
0:22:33
|
in the first place
|
|
0:22:35
|
or you can't reason through
|
|
0:22:36
|
within a reasonable amount of time
|
|
0:22:40
|
how can I solve this
|
|
0:22:43
|
per the particular requirements that they are asking.
|
|
0:22:46
|
So we're not going to be spending
|
|
0:22:49
|
pretty much any time at all talking about
|
|
0:22:51
|
the "gotchas" of the lab exam.
|
|
0:22:54
|
Technically there is no such thing as a "gotcha"
|
|
0:22:57
|
within CCIE technologies.
|
|
0:23:00
|
What a "gotcha" basically means
|
|
0:23:03
|
is that it's some behavior of the technology
|
|
0:23:07
|
that you don't understand.
|
|
0:23:10
|
So, for example, let's say like with OSPF version 2,
|
|
0:23:14
|
if you advertise a loopback interface into OSBF
|
|
0:23:18
|
if the subnet mask is /24, by default when you advertise it in,
|
|
0:23:23
|
it's going to show up in the database as /32.
|
|
0:23:27
|
This is because OSPF has the network type loopback
|
|
0:23:30
|
that is for software loopbacks and physical hardware loopbacks.
|
|
0:23:36
|
Now this isn't a "gotcha" of OSPF,
|
|
0:23:39
|
it simply the behavior that is defined
|
|
0:23:42
|
by the RFC.
|
|
0:23:43
|
So there is a specific reason why the loopback network type is there
|
|
0:23:47
|
it's for testing reachability
|
|
0:23:49
|
if you need to do a hardware loopback to your provider
|
|
0:23:52
|
but you still need to advertise this address in the IGP
|
|
0:23:56
|
in order to test the reachability to it.
|
|
0:23:59
|
So it's really not that this is a trick or a stupid router trick on the IOS
|
|
0:24:07
|
it's some sort of fundamental behavior of the technology
|
|
0:24:11
|
that you may not understand because you spent too much time
|
|
0:24:15
|
just going through lab scenarios
|
|
0:24:17
|
and not enough time really learning
|
|
0:24:19
|
how that particular technology works.
|
|
0:24:23
|
So really in the end, there are no shortcuts to passing this lab exam.
|
|
0:24:28
|
If you understand at a fundamental level
|
|
0:24:30
|
how all of these technologies work
|
|
0:24:32
|
then it's not going to matter what they ask you in the exam.
|
|
0:24:37
|
Now this second method that I have here
|
|
0:24:40
|
the "How Not to Prepare for the CCIE Lab Exam"
|
|
0:24:43
|
this is typically the candidates that we see
|
|
0:24:45
|
that take the lab exam six, seven, eight, nine, or even ten times
|
|
0:24:50
|
before they pass because they're really skipping over
|
|
0:24:54
|
what are the foundations of the topics
|
|
0:24:57
|
and trying to shoot just for these really corner case scenarios
|
|
0:25:02
|
that a lot of time the lab exam doesn't even test on.
|
|
0:25:05
|
So if you understand how MPLS works
|
|
0:25:08
|
from a general technology point of view
|
|
0:25:11
|
then you should be able to reason through
|
|
0:25:14
|
what is the particular design problem they're showing me
|
|
0:25:16
|
and then what are the configuration steps
|
|
0:25:18
|
I need to do in order to solve this
|
|
0:25:20
|
or if it's within the troubleshooting section,
|
|
0:25:24
|
then what are the different steps I need to go through
|
|
0:25:27
|
to find what the problem is.
|
|
0:25:29
|
So the key that we're going to be focusing on for this class
|
|
0:25:32
|
is really understanding at a fundamental level
|
|
0:25:34
|
how these technologies work.
|
|
0:25:36
|
So if you understand how that works
|
|
0:25:38
|
you will pass the lab exam as a byproduct of being an expert.
|
|
0:25:44
|
Now also, if you do pass the lab exam
|
|
0:25:46
|
just by memorizing lab scenarios,
|
|
0:25:49
|
memorizing configuration syntax, and the troubleshooting section
|
|
0:25:56
|
then ultimately when you go to apply your knowledge in the real world
|
|
0:26:00
|
let's say you're at a technical interview for a job
|
|
0:26:03
|
they will be able to tell someone that really understands
|
|
0:26:07
|
what they're talking about,
|
|
0:26:07
|
really understands how these technologies work,
|
|
0:26:10
|
or someone who just passed the exam based on sheer luck
|
|
0:26:14
|
or maybe they cheated by doing brain dumps with somebody else.
|
|
0:26:18
|
So really it depends on what is your motivation for getting the CCIE.
|
|
0:26:22
|
Do you really want to understand how this stuff works
|
|
0:26:25
|
to be able to apply it in real production networks
|
|
0:26:29
|
or is it just some type of trophy that you're trying to get?
|
|
0:26:34
|
But in the vast majority of the cases,
|
|
0:26:37
|
the candidates that we see,
|
|
0:26:38
|
they actually want to use these technologies in the real world
|
|
0:26:41
|
so the key is to understand how they work,
|
|
0:26:44
|
then it doesn't matter what questions they're asking us
|
|
0:26:47
|
or what we see in the real world
|
|
0:26:49
|
because a lot of this is developing a structured learning process
|
|
0:26:55
|
and a structured reasoning process
|
|
0:26:58
|
because as you know,
|
|
0:27:00
|
if you're going to be in the technology field
|
|
0:27:02
|
let's say five, ten, twenty more years,
|
|
0:27:05
|
the topics that we're talking about now,
|
|
0:27:07
|
they're not going to be the same stuff that's going on
|
|
0:27:09
|
in five or ten years or even probably next year.
|
|
0:27:12
|
So the key is that if you're going to be in this field
|
|
0:27:15
|
you're constantly going to be going through a learning process
|
|
0:27:18
|
figuring out what are the new technologies,
|
|
0:27:21
|
how does this fit into my design,
|
|
0:27:22
|
how do I implement this,
|
|
0:27:24
|
and preparing for the CCIE,
|
|
0:27:26
|
especially if you focus on this foundational knowledge
|
|
0:27:30
|
about how the technologies work,
|
|
0:27:32
|
then you'll find in the long run
|
|
0:27:35
|
it's going to be easier to learn new topics
|
|
0:27:36
|
and to apply them as the technologies continue to change.
|
|
0:27:41
|
Now the way that we can do this specifically
|
|
0:27:44
|
is by applying a structured approach to our learning process.
|
|
0:27:50
|
Now, this step-by-step process is what I use personally
|
|
0:27:54
|
and what Brian Dennis has used in the past
|
|
0:27:57
|
and Peter and pretty much all successful candidates that I've seen
|
|
0:28:01
|
go through this same type of logic
|
|
0:28:03
|
when they're learning a new technology.
|
|
0:28:06
|
Okay, the problem with candidates that take the lab exam
|
|
0:28:10
|
over and over and over
|
|
0:28:12
|
is that they skip to step four
|
|
0:28:15
|
before doing steps one, two, and three.
|
|
0:28:19
|
So regardless of what technology we're talking about,
|
|
0:28:21
|
let's say IP version 6,
|
|
0:28:24
|
okay, so really there's not that many people
|
|
0:28:26
|
that have real world deployment experience with IPv6 yet.
|
|
0:28:29
|
If we look at the BGP table on the internet
|
|
0:28:32
|
of the addresses that are advertised in the IPv6
|
|
0:28:35
|
there is like 500 networks total
|
|
0:28:38
|
that are advertised versus the 300,000+
|
|
0:28:41
|
that are advertised for IPv4.
|
|
0:28:44
|
So in reality not that many people are using it yet.
|
|
0:28:47
|
So when you're learning this topic
|
|
0:28:50
|
the first step would be to understand
|
|
0:28:52
|
what is IPv6 to begin with?
|
|
0:28:55
|
So just gaining a basic understanding of what is the technology,
|
|
0:28:58
|
what is the problem that it's trying to solve in the first place?
|
|
0:29:02
|
Now once I know the basics about the protocol
|
|
0:29:05
|
then I'm going to try some of this out on the command line.
|
|
0:29:07
|
So basic configurations, just doing IPv6 addressing,
|
|
0:29:11
|
maybe static routing for IPv6,
|
|
0:29:14
|
some basic IGP protocols,
|
|
0:29:16
|
looking at just what is the minimum basic configuration
|
|
0:29:19
|
you would need to use
|
|
0:29:21
|
in order to implement this type of topic.
|
|
0:29:24
|
Once I understand that, then I'm going to go back
|
|
0:29:27
|
to the technology and the technology explanation
|
|
0:29:32
|
and get an expert level of understanding.
|
|
0:29:35
|
So this is where we get into the real nitty gritty details
|
|
0:29:37
|
about how the protocol works.
|
|
0:29:40
|
So some of the advanced implementations like IPv6 tunneling,
|
|
0:29:44
|
IPv6 network address translation,
|
|
0:29:48
|
so we don't want to learn these type of topics
|
|
0:29:51
|
without really understanding in the first place
|
|
0:29:53
|
what is this technology designed to do
|
|
0:29:57
|
and what is the most basic implementation?
|
|
0:30:00
|
Now usually up-front, this type of method
|
|
0:30:04
|
is going to take more time to learn the topic
|
|
0:30:06
|
but when you look at this in the long run
|
|
0:30:09
|
you're really going to save time in your preparation process
|
|
0:30:14
|
and then most likely financial resources
|
|
0:30:16
|
as you are taking the lab exam
|
|
0:30:19
|
and as you're dedicating time for your studies.
|
|
0:30:26
|
So as we know, the CCIE is not only
|
|
0:30:30
|
a financial investment
|
|
0:30:33
|
it's a big investment of time.
|
|
0:30:36
|
So sometimes it's, or actually a lot of times,
|
|
0:30:37
|
it's hard for people to balance the study schedule
|
|
0:30:41
|
with your work schedule and family schedule
|
|
0:30:43
|
so if you can figure out what is the most efficient way
|
|
0:30:47
|
for you to understand and retain
|
|
0:30:49
|
the technology information about these topics
|
|
0:30:52
|
that's what you want to go for.
|
|
0:30:54
|
But if you keep shooting just for step number four
|
|
0:30:58
|
which is banging your head against the keyboard
|
|
0:30:59
|
trying to do the expert level configurations
|
|
0:31:02
|
without really understanding how does this technology work
|
|
0:31:05
|
or what is it designed to do in the first place
|
|
0:31:08
|
that method of skipping to step four
|
|
0:31:10
|
is going to take much more time in the long run
|
|
0:31:13
|
and an investment in, like I said,
|
|
0:31:16
|
both your finances and your time.
|
|
0:31:18
|
Okay, so let's talk about some of the specific resources
|
|
0:31:22
|
that we can use for
|
|
0:31:26
|
the lab preparation process.
|
|
0:31:29
|
Okay, first and foremost, as most of us probably already know,
|
|
0:31:32
|
there's tons and tons of books
|
|
0:31:34
|
that are dedicated to the technologies that are within the scope
|
|
0:31:37
|
of routing and switching
|
|
0:31:39
|
and then also for the particular lab exam itself.
|
|
0:31:43
|
Then two other places I'm going to show
|
|
0:31:46
|
some demonstrations of the technology documentation
|
|
0:31:49
|
on Cisco's website
|
|
0:31:50
|
then the actual product documentation
|
|
0:31:53
|
and this third point, the product documentation,
|
|
0:31:57
|
or what used to be called to Doc CD,
|
|
0:32:00
|
we're going to be spending a lot of time on this during class
|
|
0:32:04
|
to make sure we understand where
|
|
0:32:05
|
each and every technology is documented.
|
|
0:32:10
|
Now the reason that this is so important
|
|
0:32:12
|
is that this is the only technical resource
|
|
0:32:14
|
you will have available to you
|
|
0:32:17
|
when you get to the actual lab exam.
|
|
0:32:20
|
So if I'm trying to implement DATP Server
|
|
0:32:24
|
but I don't remember the syntax offhand
|
|
0:32:27
|
I'm going to need to go to the documentation CD
|
|
0:32:29
|
to figure out how that works.
|
|
0:32:31
|
But if it takes me an hour to figure out
|
|
0:32:33
|
where the DATP document is,
|
|
0:32:36
|
then it's very likely I'm going to be able to pass the exam.
|
|
0:32:40
|
So we'll spend a lot of time on the documentation CD
|
|
0:32:43
|
and make sure that we understand
|
|
0:32:44
|
where all of the topics are located
|
|
0:32:46
|
because the search function will not be available to us.
|
|
0:32:50
|
So you do need to know the manual navigation path
|
|
0:32:53
|
basically for every possible topic that's in the blueprint.
|
|
0:32:57
|
So here we have a recommended book list
|
|
0:33:01
|
that's basically split into two different parts.
|
|
0:33:03
|
The first is the Vendor Independent Resources.
|
|
0:33:06
|
This is where you can find just general technology information
|
|
0:33:09
|
about Layer 2 switching logic,
|
|
0:33:12
|
Layer 3 routing logic,
|
|
0:33:14
|
and then the different protocols like IPv6, MPLS, the IVPS, and BGP.
|
|
0:33:20
|
It would be this first one and fourth one
|
|
0:33:24
|
that are general information about the logic of routing and switching
|
|
0:33:30
|
where the second and the third one,
|
|
0:33:33
|
Internetworking with TCP/IP and TCP/IP Illustrated,
|
|
0:33:36
|
really these are the nitty gritty details
|
|
0:33:38
|
behind how IP version 4 works.
|
|
0:33:42
|
So usually you could probably read one of these
|
|
0:33:44
|
but you don't necessarily need both of them.
|
|
0:33:47
|
But either TCP/IP Illustrated or Internetworking with TCP/IP
|
|
0:33:51
|
these are great resources to have on your bookshelf
|
|
0:33:55
|
if six months from now you need to look at
|
|
0:33:57
|
what's the frame format of UDP
|
|
0:34:00
|
or what is the IP type of service field in the IP version 4 header.
|
|
0:34:05
|
So it's a lot of the details about the general IP protocol
|
|
0:34:09
|
but not the specifics of how Cisco implements it
|
|
0:34:12
|
or how other vendors implement it.
|
|
0:34:15
|
So generally it's a better idea to go for the vendor independent resources first
|
|
0:34:21
|
so that when you need to apply
|
|
0:34:24
|
Layer 2 switching onto not only Cisco Catalyst switches,
|
|
0:34:28
|
but Extreme or whatever other switching vendors are out there,
|
|
0:34:32
|
the logic of spanning tree, the logic of EtherChannel,
|
|
0:34:36
|
the logic of rapid spanning tree,
|
|
0:34:39
|
a lot of these protocols are going to be standardized
|
|
0:34:42
|
regardless of which particular vendor's implementation
|
|
0:34:44
|
you are looking at.
|
|
0:34:47
|
So then when you go to learn a new vendor's equipment
|
|
0:34:51
|
let's say you're learning how Juniper's operating system works,
|
|
0:34:55
|
at that point, it's just a matter of what the syntax is.
|
|
0:34:59
|
So I understand how OSP version 2 works
|
|
0:35:02
|
from a fundamental level.
|
|
0:35:03
|
There's no difference between how Cisco implements this
|
|
0:35:07
|
and Juniper implements it
|
|
0:35:09
|
other than the interface for the syntax.
|
|
0:35:15
|
Okay, the last one here, MPLS Enabled Applications,
|
|
0:35:18
|
this is by far the best resource I've seen
|
|
0:35:21
|
for MPLS topics
|
|
0:35:24
|
but for routing and switching a lot of this
|
|
0:35:25
|
is going to be outside of the scope.
|
|
0:35:27
|
So things like the Layer 2 VPNs
|
|
0:35:31
|
and the traffic engineering for MPLS
|
|
0:35:36
|
that stuff will not be within the scope of routing and switching
|
|
0:35:39
|
but if you want to go above and beyond
|
|
0:35:42
|
what's within the topic domain,
|
|
0:35:43
|
this is definitely the best book to look at.
|
|
0:35:46
|
It does have really good coverage of the Layer 3 VPNs
|
|
0:35:51
|
which is what we are going to be focusing on
|
|
0:35:53
|
when we get to MPLS
|
|
0:35:55
|
but it does go above and beyond that
|
|
0:35:56
|
for a lot of the other topics.
|
|
0:36:00
|
So next we have the Cisco specific books.
|
|
0:36:02
|
These are the CISCO Press ones.
|
|
0:36:04
|
A lot of these are standard texts that you've probably seen in the past
|
|
0:36:07
|
as you're preparing for maybe CCNA or CCNP;
|
|
0:36:11
|
things like Routing TCP/IP, Volumes 1 and 2,
|
|
0:36:14
|
this would be by far the best resource
|
|
0:36:18
|
for how Cisco implements the IGPs and BGP
|
|
0:36:23
|
in IOS. Okay? I think there's also some other coverage
|
|
0:36:27
|
like Multicast and some other topics in there
|
|
0:36:31
|
but this is looking at from a Cisco center point of view
|
|
0:36:35
|
how do we implement these protocols.
|
|
0:36:38
|
Now the first one, Cisco LAN Switching,
|
|
0:36:40
|
this is a little bit older and it mainly focuses on syntax
|
|
0:36:44
|
that is in the Catalyst, which is the older 5000s
|
|
0:36:51
|
and the older 6000s series
|
|
0:36:53
|
so today this is really not good for a syntax reference
|
|
0:36:57
|
but the logic of how bridging works,
|
|
0:37:00
|
the logic of how spanning tree works,
|
|
0:37:02
|
this stuff doesn't change
|
|
0:37:05
|
versus what the syntax is.
|
|
0:37:08
|
So if you were to read this to get a good understanding
|
|
0:37:10
|
of how bridging works,
|
|
0:37:12
|
then you could supplement it with the configuration guides
|
|
0:37:16
|
for the Catalyst 3560 or for the Catalyst 6500
|
|
0:37:20
|
because at that point we're just looking at
|
|
0:37:22
|
what's the particular syntax we need to implement.
|
|
0:37:27
|
Okay, the third one there, Internet Routing Architectures,
|
|
0:37:30
|
this is dedicated just to BGP
|
|
0:37:36
|
and there are a lot of topics here
|
|
0:37:39
|
that are not covered in Internet Routing Architectures
|
|
0:37:42
|
because it's a little bit older now.
|
|
0:37:45
|
It's probably older; it's probably over 10 years old,
|
|
0:37:48
|
but the core of BGP routing and BGP logic
|
|
0:37:53
|
hasn't changed from its original implementation
|
|
0:37:56
|
but there may be new features that aren't covered in there.
|
|
0:37:59
|
So, one of them specifically that we will look at
|
|
0:38:03
|
is how the VPNv4 routing works
|
|
0:38:08
|
for MPLS networks
|
|
0:38:11
|
and how we can take IGP information
|
|
0:38:14
|
like OSPF and encode the attributes into BGP updates
|
|
0:38:18
|
in order to be sent over the MPLS networks.
|
|
0:38:22
|
But for the core of BGP,
|
|
0:38:23
|
things like how does IBGP work versus EBGP,
|
|
0:38:28
|
how does route reflection confederation work,
|
|
0:38:30
|
how does path selection work,
|
|
0:38:31
|
then that stuff is all going to be covered
|
|
0:38:33
|
in Internet Routing Architectures.
|
|
0:38:37
|
Next, MPLS Fundamentals, this one is fairly recent
|
|
0:38:40
|
so that's a good resource when you're first getting into the syntax implementation
|
|
0:38:45
|
of MPLS on Cisco IOS.
|
|
0:38:48
|
There's also a separate one that's called something like
|
|
0:38:52
|
MPLS Configuration on Cisco IOS.
|
|
0:38:54
|
There's a lot of good examples in that book
|
|
0:38:56
|
that you can use on the IOS to actually test out how this stuff works.
|
|
0:39:04
|
Then we have Developing IP Multicast Networks.
|
|
0:39:07
|
Again, this is a little bit older now
|
|
0:39:11
|
but the core technology of how PIM dense mode
|
|
0:39:15
|
and PIM sparse mode works has not changed
|
|
0:39:17
|
but it's not going to talk about some of the newer technologies
|
|
0:39:21
|
like source specific Multicast or Anycast RP
|
|
0:39:25
|
but these are really going to be just the minor details
|
|
0:39:28
|
on top of PIM where this book does have great coverage
|
|
0:39:32
|
of the core technology of how PIM sparse and dense works.
|
|
0:39:38
|
Then implementing IPv6 networks
|
|
0:39:40
|
Most of this is going to be a good syntax reference for IPv6,
|
|
0:39:45
|
how a lot of the configurations work,
|
|
0:39:47
|
but for a technology understanding
|
|
0:39:49
|
I would definitely recommend the previous one
|
|
0:39:52
|
which is the IPv6 Theory, Protocol, and Practice.
|
|
0:39:56
|
So this one talks about IPv6
|
|
0:39:58
|
just from a generic technology point of view
|
|
0:40:01
|
and from an RFC standard point of view
|
|
0:40:04
|
where implementing Cisco IPv6 networks
|
|
0:40:08
|
would then talk about Cisco specific implementations,
|
|
0:40:11
|
so how the syntax works.
|
|
0:40:16
|
Lastly, we have the Cisco QoS Exam Certification Guide.
|
|
0:40:21
|
This is by far the best reference for Quality of Service in Cisco IOS.
|
|
0:40:27
|
It does have some coverage of both Layer 2 and Layer 3 QoS
|
|
0:40:31
|
and really there's not many vendor independent books
|
|
0:40:34
|
that you would see on this
|
|
0:40:36
|
because QoS is always a proprietary implementation.
|
|
0:40:40
|
So the way that Juniper does QoS
|
|
0:40:43
|
versus how Cisco does QoS,
|
|
0:40:45
|
it's going to be completely different.
|
|
0:40:49
|
Now you can get this book list
|
|
0:40:51
|
if you go to ine.com/resources.
|
|
0:40:55
|
The other thing that I would recommend to do
|
|
0:40:57
|
if you haven't seen this before
|
|
0:40:59
|
is to go to either the Cisco press website
|
|
0:41:02
|
or if you go to safari.oreilly.com
|
|
0:41:08
|
now it's my safari books online
|
|
0:41:11
|
and let me see if I know what my login is here.
|
|
0:41:23
|
And what this is, is essentially an electronic version
|
|
0:41:28
|
of the entire Cisco Press library
|
|
0:41:30
|
plus all of the other books
|
|
0:41:32
|
that are under the O'Reilly publishing umbrella.
|
|
0:41:35
|
So there's tons and tons of book here
|
|
0:41:37
|
that relate not only to networking
|
|
0:41:39
|
you can see like Java Development,
|
|
0:41:41
|
Web Development, Microsoft Development,
|
|
0:41:43
|
but what's really nice about this site
|
|
0:41:45
|
is that when you get into the later stages of your preparation,
|
|
0:41:49
|
and you're looking for something very, very specific,
|
|
0:41:52
|
it's easier to use the search engine of Safari
|
|
0:41:56
|
to figure out what is the particular chapter of the book
|
|
0:41:59
|
and even the particular paragraph
|
|
0:42:01
|
that is talking about this topic
|
|
0:42:03
|
versus flipping through 1,000 pages
|
|
0:42:06
|
of Routing TCP/IP Volumes 1 and 2.
|
|
0:42:10
|
So let's say something very specific,
|
|
0:42:12
|
let's say like EIGRP stub routing.
|
|
0:42:21
|
So this brings us to a couple of different books.
|
|
0:42:23
|
You can see some of them are not Cisco Press.
|
|
0:42:26
|
This is actually a really good book here,
|
|
0:42:27
|
the Cisco IOS Cookbook.
|
|
0:42:30
|
But then it links to also CCIE Practical Studies Volume I
|
|
0:42:35
|
which is for some lab scenarios.
|
|
0:42:40
|
Then let's see, the CCMP Route Exam,
|
|
0:42:43
|
but what's nice about this
|
|
0:42:44
|
if you click on the particular result,
|
|
0:42:48
|
it takes you directly to the particular section
|
|
0:42:51
|
of the book that talks about that.
|
|
0:42:55
|
So some of these resources,
|
|
0:42:57
|
it's better to have in printed format,
|
|
0:42:59
|
at least in my opinion,
|
|
0:43:01
|
because if I'm sitting down to read for an hour
|
|
0:43:04
|
a lot of times I don't like to do that on my computer screen.
|
|
0:43:07
|
But if I'm just quickly looking for a very specific example
|
|
0:43:12
|
then Safari is a great resource to use this.
|
|
0:43:16
|
So I think they have a couple of different levels
|
|
0:43:17
|
of subscriptions where you can choose like 10 books
|
|
0:43:19
|
or you can get all of them.
|
|
0:43:21
|
If you look at the price of any of these books retail,
|
|
0:43:24
|
a lot of the times the Cisco Press books
|
|
0:43:26
|
are going to be like $80 or $90 to begin with.
|
|
0:43:29
|
So figure if you get the subscription
|
|
0:43:31
|
for maybe three or six months
|
|
0:43:33
|
especially towards the end of your preparation,
|
|
0:43:35
|
it usually ends up to be a really good investment
|
|
0:43:39
|
versus a lot of the printed resources.
|
