All language subtitles for Free-CCNA-EtherChannel-Day-23-CCNA-200-301-Complete-Course_en

This is a free, complete course for the CCNA.

If you like these videos, please subscribe\n

Also, please like and leave a comment, and\n

In this video we will look at another topic,\nEtherChannel.

EtherChannel allows you to group multiple\n

as a single logical interface, so they behave\n

There are many benefits to this, and I’ll\n

By the way, this video covers topic 2.4 of\n

that you must be able to configure and verify\n

called LACP, Link Aggregation Control Protocol.

So, what will we cover in this video?

First off, I’ll show you what EtherChannel\n

Here’s a hint, spanning tree protocol is\nthe big problem.

We will also look at multiple methods of configuring\n

A Layer 2 etherchannel is a group of switch\n

and a Layer 3 etherchannel is a group of routed\n

which you assign an IP address to, because\nit’s Layer 3.

Make sure you watch until the end of the video\n

ExSim, the best practice exams for the CCNA.

I used Boson ExSim to help me prepare for\n

it was the key that allowed me to pass\n

Okay, let’s get started with the video.

So, let me demonstrate a problem.

We have two switches here, ASW1 and DSW1.

I will talk about basic network design later\n

which is a switch that end hosts like PCs\n

DSW stands for distribution layer switch,\n

For this demonstration, let’s say there\n

say 40 hosts, and they are all trying to access\n

The network administrator notices that the\n

that he should add another link to increase\n

So, the network admin adds another link, and\n

However, the additional link doesn’t seem\nto help.

The connection between ASW1 and DSW1 is still\n

So, the admin decides to add another link\nbetween ASW1 and DSW1.

He adds another link to the connection between\nASW1 and DSW1.

Surely, this will be sufficient.

The total bandwidth of the connections to\n

of the connection to DSW1, but that’s okay,\n

a constant state of sending and receiving\nInternet traffic.

I will talk more about this later in the course,\n

to end hosts is greater than the bandwidth\n

this is called oversubscription.

Some oversubscription is acceptable, but too\n

However, even with three links to DSW1 the\n

network admin once again decides to add another\n

So, now there are four links between ASW1\nand DSW1.

Do you think things have improved?

Well, they haven’t, the connection between\n

You should be able to figure out the answer.

Here’s a hint, think about what you just\n

If you know the answer, well done, if not\n

Let’s say the administrator went to physically\n

What color do you think they were?

Well, the network admin checks DSW1 and all\n

However, when he checks ASW1 he notices that,\n

is green, and the others are orange.

It’s because of what we studied in the past\n

If you connect two switches together with\n

Well, if all of ASW1’s interfaces were forwarding,\n

DSW1, leading to broadcast storms.

Other links will be unused unless the active\nlink fails.

In that case, one of the inactive links will\nstart forwarding.

So, although having backup links is a good\n

reasons, it’s a waste of bandwidth to have\n

However, by forming these four physical interfaces\n

solve this problem, giving us both redundancy\n

An EtherChannel is represented in network\n

that are grouped together, like this.

EtherChannel groups multiple interfaces together\n

STP will treat this group as a single interface.

So, after grouping these interfaces into an\n

Won’t this cause a Layer 2 loop?

Actually no, because this group of four links\n

For example, let’s say a PC sends a broadcast\nframe.

So, it is flooded out all interfaces on ASW1.

All of the PCs connected to ASW1 will receive\n

Now, how many copies of the frame will DSW1\nreceive?

Remember, although there are four physical\n

The answer is, DSW1 will only receive one\ncopy.

This EtherChannel makes these four physical\n

won’t sent four copies of the same broadcast\n

Traffic using the EtherChannel will be load\n

An algorithm is used to determine which traffic\n

I will give you more details on this later.

So, DSW1 received the broadcast frame.

It will flood the broadcast frame out of all\n

So let’s say DSW1 has these two other links\nhere.

Which interfaces will DSW1 forward the frame\nout of?

Why didn’t it forward the frame out of the\n

I’ll repeat it once more, although this\n

interfaces, they behave as a single interface.

DSW1 won’t send the broadcast frame back\n

So it isn’t forwarded back to ASW1, and\n

It’s kind of like this, instead of four\n

interfaces, connecting ASW1 to DSW1, it’s\n

The bandwidth of the four separate interfaces\n

a virtual four-gigabit interface.

The difference between the physical characteristics\n

of a network are something you need to understand\n

Multiple PCs can all be connected to the same\n

VLANs virtually divide these PCs into separate\n

Likewise, these interfaces exist as four separate\n

Some other names for an EtherChannel are a\n

You’ll see that, to configure an etherchannel\n

Now let’s take a look at how etherchannel\nload balances.

It load balances based on ‘flows’.

A flow is a communication between two nodes\nin the network.

So for example, between PC1 and SRV1.

By the way, you usually won’t see a server\n

layer switch, these are also end hosts which\n

Just to simplify this network diagram I’ll\n

So, let’s say PC1 initiates an exchange\n

The frame is received by ASW1, and assuming\n

it will forward the frame out of the port\nchannel to DSW1.

However, which physical interface will it\nuse?

Well, there is an algorithm it uses to calculate\n

actually be sent on, let’s say it determines\n

Now, when PC1 sends the next frame in the\n

SRV1, the same interface will be used to forward\n

So, the point is that frames in the same flow\n

If frames in the same flow were forwarded\n

frames may arrive at the destination out of\n

Some applications can deal with frames arriving\n

Now, if PC1 wants to print something and initiates\n

will once again forward the frame using its\n

However, it will make a separate calculation\n

For example, it might determine that this\n

Just like before, when PC1 sends another frame\n

the etherchannel will be used to forward it.

How about if PC2 also wants to print something?

It sends the first frame in the flow to ASW1,\n

which physical interface in the etherchannel\nwill be used.

So, this is how EtherChannel performs load\n

in the etherchannel for different flows.

The calculation that is done to determine\n

Actually, you can change the inputs used in\n

Here are the inputs that can be used.

So, all frames with the same source MAC address\n

In this case, all frames with the same destination\n

You can also use both the source AND destination\nMAC addresses.

So for example, frames from PC1 to SRV1 will\n

from PC2 to SRV1 will always use a certain\n

than the one used for traffic from PC1 to\n

The calculation is done based on both the\n

You can also configure etherchannel to select\n

destination IP address, or both source AND\n

Some switches also support load-balancing\n

but those are a topic for another lesson.

Also, which methods the switch can use depends\n

using the MAC addresses, some may support\n

So, we haven’t actually configured an etherchannel\n

take a look at how to check and configure\n

Use the command SHOW ETHERCHANNEL LOAD-BALANCE\n

You can see the default for this model of\n

So, for example, all traffic from 10.0.0.1\n

use a certain physical interface within the\netherchannel.

Down here you can see a more specific breakdown.

Frames which encapsulate IP packets, whether\n

on the source and destination IP addresses.

However, notice at the top it says non-IP\n

Well, that’s because if an IP packet isn’t\n

is no IP address that can be used to determine\n

Now, as for how to change the load-balancing\n

PORT-CHANNEL LOAD-BALANCE, followed by the\nmethod.

In this case I changed it to use the source\n

Then I confirmed once more, and you can see\n

By the way, here are the choices available\non this device.

It can load-balance based on MAC or IP addresses,\n

on either the source, the destination, or\n

Now, I want to point out one thing which is\n

What keyword do you use to configure the load-balancing method?

And what keyword do you use to view the load-balancing\nmethod?

Different words are used for the same thing,\n

Actually, later you’ll find that there is\n

So, these are the first two commands to remember\nfor this video.

SHOW ETHERCHANNEL LOAD-BALANCE, to check the\n

And, PORT-CHANNEL LOAD-BALANCE, followed by\n

Now let’s get into actually creating an\n

There are three methods of EtherChannel configuration.

First up is PAgP, which stands for Port Aggregation\nProtocol.

It is a Cisco proprietary protocol, so it\n

If you’re trying to form an EtherChannel\n

It dynamically negotiates the creation and\n

Just a few days ago we covered DTP, which\n

Frames are sent to the neighboring switch\n

and then the switches agree upon either forming\n

Okay, the next method of configuration is\n

It is an industry standard protocol, once\n

Basically, it does the same thing as PAgP.

It dynamically negotiates the creation and\n

Because it is an industry standard protocol,\n

it can be used to form EtherChannels with\n

Because of this, LACP is the preferred method\n

Actually, the exam topics list only states\nLACP.

However, for the test you really should be\n

reason Cisco’s exam topics lists aren’t\nvery reliable.

So, the last method is static EtherChannel.

In this case a protocol isn’t used to determine\n

Instead, interfaces are statically configured\n

This is usually avoided, because you want\n

for example you want the switch to remove\n

is some sort of problem on the interface.

Okay, finally, up to 8 interfaces can be formed\n

Actually, LACP allows up to 16, but only 8\n

mode, waiting for an active interface to fail.

So let’s look into how to configure each\nmethod.

The configuration for each is almost identical,\n

First I used the interface range command to\n

This is a good idea for EtherChannel, because\n

must match, so if you configure them all at\n

I’ll talk more about that after I show you\nthe configurations.

Anyway, to actually configure the EtherChannel\n

CHANNEL-GROUP, followed by a number that identifies\n

can see I used the question mark to see what\noptions there are.

There are five options, two of them are used\n

Do you recognize these names from another\n

DTP used the same modes to form trunks, and\n

Desirable mode actively tries to form an EtherChannel,\n

if the other side is set to desirable, but\n

If both sides of the connection are set to\n

However, auto and desirable, or desirable\n

Anyway, I decided to configure this side as\ndesirable.

You can see that the virtual port-channel\n

used in the channel-group command.

You can see it here in the output of the SHOW\n

So, remember that the CHANNEL-GROUP command\n

the name of the virtual interface that is\n

By the way, this channel group number has\n

however it DOESN’T have to match the channel-group\n

For example, channel-group 1 on ASW1 can form\n

The number is just used to identify the virtual\n

Because you can have multiple etherchannels\n

Next let’s look at LACP configuration.

After explaining all of that, there’s not\n

Just notice that mode names are different.

Instead of desirable, LACP uses active mode.

And instead of auto, LACP uses passive mode.

So, if both ends are configured in passive\n

However, active and passive, or active and\n

In this case, I configured this side as active.

Once again, the port-channel interface is\ncreated.

Note that, even if you configure both sides\n

However, it won’t actually be functioning\n

So, as you can see the command is basically\n

Once again, the channel-group number has to\n

switch, but it doesn’t have to match the\n

Finally, let’s see how static EtherChannel\nis configured.

There aren’t two separate modes, just one,\n

This will create a port-channel interface,\njust like before.

By the way, on mode only works with on mode.

On and desirable, or on and active will not\n

Another command you should know is the CHANNEL-PROTOCOL command.

This manually configures the EtherChannel\n

This actually isn’t a very useful command,\n

If you configure CHANNEL-GROUP 1 MODE DESIRABLE\n

use PAgP, or if you configure CHANNEL-GROUP\n

So, there isn’t really a point in using\nthis command.

However, I think you should know it for the\n

Of course there are two options, LACP and\n

Then I tried the CHANNEL-GROUP 1 MODE DESIRABLE\n

I manually configured these interfaces to\n

If I try CHANNEL-GROUP 1 MODE ON it is rejected\nas well.

Then I do CHANNEL-GROUP 1 MODE ACTIVE, and\n

So, after configuring the EtherChannel, in\n

can then configure the port-channel interface\nitself.

Note that I’m just using the LACP example\n

same regardless of which method you use.

I also did the same configurations over on\n

I entered interface config mode for the port-channel\n

Now in the output of SHOW INTERFACES TRUNK,\n

Notice that the individual physical interfaces\n

Here’s a section of the output of SHOW RUNNING-CONFIG.

There’s something interesting to notice\nhere.

The trunk configurations that I configured\n

to the physical interfaces, I didn’t manually\n

Now, one more important point about EtherChannel\nconfiguration.

Member interfaces, the physical interfaces\n

They must have the same duplex setting.

They must have the same speed.

They must have the same switchport mode, meaning\n

If they are a trunk, they must have the same\n

If an individual interface’s configurations\n

When it comes to verifying the status of an\n

useful command is SHOW ETHERCHANNEL SUMMARY.

Down here is a list of the port-channel interfaces\n

Next to port-channel 1 it has two flags, an\n

To check the meaning of these, look at the\nlegend up top.

S means it is a Layer 2 etherchannel.

S stands for switchport, by the way.

U means in use, meaning the EtherChannel is\n

Next to the physical ports there is the flag\n‘P’.

This means that these ports are properly bundled\n

These are the flags you want to see in an\n

Now, let’s take a look at a couple situations\n

So, I shutdown the port-channel 1 interface.

Now next to both the port-channel interface\n

Okay, I’ll enable the interface again and\n

Now I changed one of the member interfaces\nto access mode.

Now it has the lower-case ‘s’ flag.

Note that this is different than the upper-case\nS flag.

So, only G0/0 is suspended, but the EtherChannel\n

Another command you can use is SHOW ETHERCHANNEL PORT-CHANNEL.

You can see the number of ports in the port-channel,\n

One important bit of information that you\n

but is displayed in this command is the channel-group\n

the CHANNEL-GROUP 1 MODE ACTIVE command earlier.

However, for EtherChannel the most common\n

I just wanted to show you one other option.

Because I started this video talking about\n

when EtherChannel is configured.

As you can see, only the port-channel interface\n

appear in the output of this command at all.

So, as I said earlier, spanning-tree is treating\n

Instead of blocking three of them, they can\n

To close off this lecture, let’s take a\n

I’ve replaced ASW1 and DSW1 with multilayer\nswitches.

Instead of a Layer 2 connection between them,\n

Modern network design often leans toward using\n

that way spanning-tree won’t be an issue\n

We could have four switches interconnected\n

with Layer 3 routed ports, all interfaces\n

to be disabled due to spanning tree.

Now you may be thinking, didn’t you just\n

doesn’t have to block any ports?

Well, we’re just looking at a connection\nbetween two switches.

Even if we’re using EtherChannel, Layer\n

are connected together in a loop.

For example, look at this diagram.

All of the connections between switches are\n

any of the port-channel interfaces, broadcasts\n

and cause a broadcast storm.

So, spanning-tree will block one of these\n

However, if all of these connections between\n

Layer 2 switchports, there is no need to run\n

Routed ports don’t forward Layer 2 broadcasts,\n

You already know how to configure routed ports\n

Let’s see how to configure a Layer 3 EtherChannel.

So, starting from a clean configuration, no\n

I enter interface range config mode for the\n

the CHANNEL-GROUP command, I use the NO SWITCHPORT\n

Then, after using the CHANNEL-GROUP command,\n

Notice that the port-channel interface that\n

Now, since we’re making a Layer 3 etherchannel,\n

Where do you think it should be configured?

It should be configured on the port-channel\ninterface.

Now, let’s check the SHOW ETHERCHANNEL SUMMARY\n

So, the only difference in the output is that\n

It means it is a Layer 3 EtherChannel, R stands\nfor routed port.

In the output of SHOW IP INTERFACE BRIEF,\n

So, now ASW1 and DSW1 are like two routers\nconnected together.

They are connected at Layer 3 and spanning-tree\n

However, just like with the Layer 2 EtherChannel,\n

Okay let’s quickly review the commands we\ncovered.

First is PORT-CHANNEL LOAD-BALANCE, followed\n

model, can involve MAC addresses, IP addresses,\n

source, destination, or both source and destination\n

interface is used to forward any specific\nflow of traffic.

To view the current EtherChannel load-balancing\n

To configure an interface to be part of an\n

followed by the port-channel number, MODE,\n

The most useful show command for EtherChannel\n

summary of all of the EtherChannels on the\n

One more show command you can use is SHOW\n

some more detailed information about the port-channel\n

Those are all of the commands we learned today.

Of course, there are many more commands that\n

deeper into the concept of EtherChannels.

As long as you understand their basic purpose\n

you should be good for the CCNA.

Okay let’s go to today’s quiz.

Watch until the end of the quiz for a bonus\n

a doubt the best practice exams for the CCNA,\n

Let’s go to question 1 of the quiz.

Which of the following channel-group mode\n

Pause the video to think about your answer.

A, on – on, creates a static EtherChannel,\n

C, desirable – auto, creates an EtherChannel\nusing PAgP.

G, active – active, creates an EtherChannel\nusing LACP.

So, A, C, and G are the correct answers.

B, passive - passive won’t create an etherchannel\n

Same for D, PAgP auto mode doesn’t actively\n

E, active – desirable, and F, on – desirable,\n

won’t result in a valid EtherChannel configuration.

In the output of the show etherchannel summary\n

in the EtherChannel you configured have the\n

A, the interfaces are in LACP passive mode.

B, the interfaces are bundled in the port-channel.

C, the interfaces are paused until the other\n

Or D, the etherchannel is a Layer 2 EtherChannel.

Pause the video to think about your answer.

The answer is B, the interfaces are bundled\nin the port-channel.

This is the flag you want to see next to the\n

Here’s some sample output of SHOW ETHERCHANNEL\nSUMMARY.

As you can see, P means the port is bundled\nin the port-channel.

Which of the following member interface parameters\n

Or D, switchport mode, access or trunk.

Pause the video to think about your answer.

The answers are C, interface speed, and D,\nswitchport mode.

These are two of the settings that have to\n

A, interface ID, is unique to each interface,\n

And even if you’re configuring a Layer 3\n

have IP addresses, the IP address must be\n

So B, IP address, is also incorrect.

Okay, next let’s take a look at a question\n

Okay, for today's Boson ExSim practice question\n

And this is a really good question, quite\nchallenging.

You issue the following commands on SwitchA\n

First, INTERFACE PORT-CHANNEL 1.

So, this isn't necessary but it creates the\n

So this virtual port-channel exists, the interface\n

made members of that virtual interface.

Okay, then we enter the INTERFACE RANGE command\n

We manually configure the channel protocol,\n

And then finally we use the CHANNEL-GROUP\n1 MODE ON command.

Now normally, as I showed you in this video,\n

port-channel interface is automatically created,\n

CHANNEL-PROTOCOL LACP, CHANNEL-GROUP 1 MODE\nON.

Again, we create the virtual port-channel\ninterface beforehand.

Enter interface range config mode for FastEthernet0/5 and 6, this

protocol as PAgP, before once again doing\n

So, which of the following statements is true\n

A, a link is formed using LACP because it\n

As you can see here, LACP was configured first.

Okay, C, a link is formed using PAgP because\n

So, it was configured here on SwitchB.

And then D, a link is formed without an aggregation\nprotocol.

So you see both of these switches used the\n

This configure static protocol (*EtherChannel),\n

So, what do you think is the answer?

Pause the video here to think about it.

Okay, hopefully you got the answer.

I think the correct answer is B, no link is\nformed.

So, first you create the port-channel interface.

So it does exist, the virtual interface.

Then you manually configure the channel protocol\n

But when you use the command CHANNEL-GROUP\n

to join this port-channel interface, to join\n

The CHANNEL-GROUP 1 MODE ON command.

Because we already manually configured LACP,\n

MODE ON will not work, the command will be\nrejected.

And then same thing on SwitchB.

This time instead of LACP it's PAgP.

So you manually configured the channel-protocol\n

exists, these interfaces won't actually join\n

So, I think B is the correct answer.

So here is Boson's explanation, quite a lengthy,\n

And this is something really great about ExSim.

If you're ever unsure about why B is correct,\n

all of these great, in-detail explanations\nhelping you out.

And then finally, at the end there are references.

This is to the official cert guide, EtherChannel\n

And then also two links to Cisco documentation,\n

Okay, so that's today's Boson ExSim practice\nquestion.

If you want to get a copy of Boson ExSim,\n

I really like these practice exams.

I used them myself for my CCNA and CCNP, so\n

So once again, follow the link in the video\n

There are supplementary materials for this\nvideo.

There is a flashcard deck to use with the\nsoftware ‘Anki’.

There will also be a packet tracer practice\n

That will be in the next video.

Sign up for my mailing list via the link in\n

the flashcards and packet tracer lab files\nfor the course.

Before finishing today’s video I want to\n

Thank you to funnydart, Joshua, Scott, Aleksa,\n

Samil, Velvijaykum, C Mohd, Johan, Mark, Miguel,\n

of ExSim, Sidi, Magrathea, Devin, Charlsetta,\n

Sorry if I pronounced your name incorrectly,\n

One of you is still displaying as Channel\n

me know and I’ll see if YouTube can fix\nit.

This is the list of JCNP-level members at\n

2020, if you signed up recently and your name\n

Please subscribe to the channel, like the\n

with anyone else studying for the CCNA.

If you want to leave a tip, check the links\nin the description.

I'm also a Brave verified publisher and accept\n