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In this video,

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we're going to cover the network platform commands

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for the exam that you need to be aware of.

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Now, when I mention the term network platforms,

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I'm talking about things like routers, switches,

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and firewalls.

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And for the exam,

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I want you to know the show interface, show config,

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and show route commands

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and how we use them in maintaining

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and troubleshooting our networks.

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So what is a network platform?

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Well, I know this sounds like a really funny term

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that CompTIA uses here,

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but when they refer to a network platform

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and the objectives,

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what they're really referring to is any router,

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switch, or firewall,

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regardless of the brand or manufacturer.

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This is because CompTIA exams

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are considered vendor neutral exams.

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So we're not asking you just about Cisco.

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We could be asking about a Cisco router, a Juniper switch,

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or a Sidewinder firewall.

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It doesn't really matter.

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They're all considered network platforms.

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Now, each device manufacturer

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does create their own command line interface

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that's going to be used to configure, monitor,

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and troubleshoot their devices,

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but they're all pretty similar

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in their actual functions and commands,

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and most of them are based off Cisco

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because they were one of the first really big

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router and switch companies out there.

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For this lesson, we're going to focus on show interface,

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show config, and show route.

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These three terms are specific to Cisco devices,

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but similar commands exist

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for other manufacturers like Juniper

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and Sidewinder devices as well.

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For the show interface command,

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you could use show interfaces with an S on it,

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on a Juniper device or CF interface,

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which stands for "configure interface"

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on a Sidewinder firewall.

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It'll give you the same type of thing.

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Now for the show config command on a Cisco device,

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you could use show configuration on a Juniper device

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or CF config on a Sidewinder device.

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Now for the show route command,

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you would still use show route on Juniper devices,

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but you'd use CF route status on a Sidewinder firewall.

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So let's take a look at these three specifically

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show interface, show config, and show route,

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and what type of information you can get from them.

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First, we have show interface.

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The show interface command is going to display the statistics

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for a network interface on the device.

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Now, if you look at the specific interface,

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instead of all of the different interfaces

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you'd want to enter show interface

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and then use the ethernet interface you want to look at.

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For example, show interface ethernet 1/1.

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This would display only the statistics for ethernet 1/1,

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that specific interface and port on that switcher router.

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Now, when you use the show interface command,

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you can see if the interface is up or down,

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if the line protocol is up or down,

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in some key statistics that'll help you determine

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if there's any network issues.

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First, you should look at whether the internet address

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is a valid address

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or do you have an APIPA address that was assigned

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because you had a DHCP issue.

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If you see an APIPA address,

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that means you need to investigate your DHCP.

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Second, you should look at the bandwidth

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and see if it matches your cable type.

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In this example, the bandwidth is set

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to 10,000 kilobits per second or 10 megabits per second.

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This means the interface

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thinks it's using a Cat 3 cable.

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Now, if this is incorrect

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and you're actually using a Cat 5 or a Cat 6 cable,

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that cable may be damaged,

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which is why the device is only reporting

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that it's capable of 10 megabits per second.

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Third, you want to look at your MTU size.

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By default, this is going to be set to 1500 bytes,

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but if you're using a storage area network,

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you might want to use jumbo frames

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and use something as large as up to 9,000 bytes in size.

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This is going to depend on what network you're looking at.

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Also, you should check to see if there's any runts, giants,

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or errors in the statistics,

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as these are all indications of potential problems.

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Finally, you should check for collisions.

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If you're running full duplex on a switch or router,

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there should not be any collisions

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because each switch port is its own collision domain.

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In this example, I see there are 432 collisions,

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which indicates there's an issue on this switch port,

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or maybe somebody's connected

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a hub to that switch port downstream.

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Now, next we have the show config.

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Now, show config is a command

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that's used to display the current system configuration

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to your screen.

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When you use the show config command,

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there are no options or arguments.

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It's just going to be entered

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as show config and you'll hit enter.

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Now for the exam, you do not need to understand

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each and every line of this configuration.

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If you move into being a network administrator

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and you decide to take your

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Cisco Certified Network Associate Certification or CCNA,

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you're going to be expected to know

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each and every line of this.

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But for now, you should be able to read

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through this configuration and identify some key areas.

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First, we have the shared secrets

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that are being stored towards

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the beginning of the configuration file,

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as well as some basic items that allow us

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to configure things like our prompt

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and our message of the day.

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Next, we get into some system settings

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such as the system baud rate,

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which is currently set to 9,600 bits per second

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when I'm communicating over a console port.

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Next, we have some SNMP settings including enabling

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or disabling some of the traps for this device

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so it can report back to an SNMP manager.

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In this case, they're all disabled.

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Next, we're going to have some IP settings

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such as those two interfaces I have:

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sc0

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and sl0.

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You can see that sc0 is being set up

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to use a Class B private IP

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of 172.16.25.142,

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and a route was set to allow traffic out the gateway router

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at 172.16.10.201.

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Now, next, we have our VMPS,

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which is the VLAN Management Policy Server.

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In this case, we have it set to a TFTP server at 1.1.1.1,

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and it is set to enable.

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Next, we have our DNS set up for this device,

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and this is set up to use two DNS servers,

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a primary one at 198.92.30.32,

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and a backup at 171.69.2.132.

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Both of these are enabled and our DNS domain is cisco.com

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because this is a sample configuration file

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that was created for use by Cisco.

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Next, we have our TACACS+ configuration,

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including its servers,

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the number of invalid attempts allowed,

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and the timeout period.

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After that, we have the configuration

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for an older protocol known as IPX,

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and this device is set to allow IPX traffic

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to be bridged into this network.

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Next, we have the VTP settings,

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which are going to allow us to be in server mode.

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Remember, VTP is the VLAN trunking protocol,

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and this is a proprietary protocol used by Cisco devices

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to exchange VLAN information.

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After that, we have some spanning tree protocol settings,

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specifically, that we've enabled STP

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and we have a max age set at 20.

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After that, we have CGMP, which is set to enable.

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Now, CGMP is not something

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we've talked about before in this course,

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but this is a Cisco specific thing.

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CGMP is the Cisco Group Management Protocol;

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It's an older form of IGMP used by Cisco switches.

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Next we have syslog,

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and in this case, it's set to enable for the console

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and it's set to disabled for the server.

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All the logging levels are set here as well,

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and you can see they're either 2 or 5.

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Anything above those numbers would not be forwarded

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or logged by Syslog.

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Now, after that, we have the NTP section,

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which configures our network time protocol server

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that we're going to use,

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including what time zone we're in

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and if we're going to enable NTP clients or not.

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After that, we have a permit list,

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which is essentially an ACL.

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In this case, the permit list is set to disable.

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Finally, we have the first module in our device,

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a 2-port 100BaseTX device,

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so this is a fast ethernet device.

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Here you could see what has been enabled and disabled

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on this particular module or interface.

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As I said, you don't need to be an expert on any of this.

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I just wanted to show you what it looked like

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inside of a configuration file

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when you use the show config command.

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Our third command is show route.

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The show route command is going to be used to display

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the current state of the routing table on the device.

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More accurately, we're normally going to enter this command

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as show IP route and hitting enter.

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This is because we normally want to see the routes

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associated with IP based networks

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for most of our networks.

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Most of us aren't running any networks that aren't IP based.

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For example, you're probably not running an IPX

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or AppleTalk network anymore.

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Now, here's an example of a router that I have

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that I've entered show IP route on.

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Here you can see first we have a legend

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that shows us all the different codes and what they mean.

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Then we see the gateway of last resort,

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which is our default gateway

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that we're going to use if we can't route traffic

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to any of the other routes that are listed below.

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As you look at those routes,

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you can see they're written in three columns.

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The first column indicates

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how the route is going to be derived.

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Is it from IGRP, RIP, OSPF, directly connected,

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a static route, EGP derived, or BGP derived.

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Then we have our second column,

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and this tells us the type of route it is

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when we learn it through OSPF.

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In this example, we have three of these type of routes,

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and they're listed as E2 for OSPF external type two routes.

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Then we have the address of the remote network

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such as 150.150.0.0,

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and then we see a pair numbers inside some brackets.

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In this example, it's one 60/five.

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This means 160 is the administrative distance

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of the information source,

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and five is the metric for this route.

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Next, we see the via and an IP address,

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which is the address of the next router

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to the remote network.

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After that, we see a time,

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and this is the last time the route was updated.

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It's written in hours, minutes, and seconds,

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so this first route is only one minute old.

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Finally, we have the interface used

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for a specified network in this route.

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In this case, Ethernet2 is designated as the path

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for sending traffic to this particular network.

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So as you can see from the show IP route command

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that OSPF routes have an administrative distance of 160

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and a metric of only 5.

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The EGP routes have an administrative distance of 200

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and a metric of either 128 or 129.

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This tells me that the router trust the OSPF routes

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more than a trust the EGP routes, right?

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Now, this makes sense if you think back

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to our previous discussions on router protocols,

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administrative distances,

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and the believability of these metrics.

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All right, let's look one more time at the show IP route,

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but this time on a different router.

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Here you can see a router that has fewer routes.

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In this router, I only have four routes.

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My default route of 160.89.0.0

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and then three subnets.

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Here you can see the connected route

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is showing it's possibly being down on Ethernet0.

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Next, we see two IGRP derived routes,

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and they're using I as level 2 as their route type.

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These routes have a lower administrative distance

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than the OSPF and EGP routes that we looked at earlier,

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but their metric is a bit higher than an OSPF one

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that we saw before.

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Now if you wanted to get additional details

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on any of these specific routes,

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you could enter show IP route

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and the IP address for that network

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to get additional details, including its routing metrics,

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reliability, the delay on the network,

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and even the hop count, as you can see here.

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So in summary, you need to remember

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that show interface gives you the statistics

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for an interface,

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that show config is used to display

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the current configuration device,

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and show route is going to be used

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to get information from the routes learned

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by a particular network device.