Time
13 hours 57 minutes
Difficulty
Beginner
CEU/CPE
14

Video Transcription

00:00
Hello and welcome back to I seen you one interconnecting Cisco networking devices. Part one, this is episode 33 to trump shooting switch problems. I'm trend there will not be instructor for this course. No s Village went over the lesson three with three introduction was pre assessment questions
00:16
This episode of recovered how to troubleshoot some basic switch configuration issues that may arise during real life and also during the exam
00:24
are learning objectives. For this, we're gonna look at the interface status codes again. We're gonna look at some speed and duplex issues and the layer one problems that can exist,
00:32
as always, a quick pre assessment. Here. What is a runt frame? I'm giving a few seconds.
00:41
All right, Hopefully you got the frames. More than 64 bites
00:46
annals. Here are this from one of the previous lessons here, this status table.
00:51
So we will go ahead and bring up.
00:54
Look, if this is some of the show commands that could be very useful to show interfaces f a zero to status or if you wanna look at all of them just to show interfaces, status neck, that'll show you
01:04
whether the area is able to get a shiver down that kind of thing. Show I p interface brief. Well,
01:11
we'll show you administratively down. It will not. Sure. Air disabled pours for port security, though. And then just show interface FAA Zahra to will show you a lot of trouble shooting. We'll use that one a little more later in this episode. So for now, I'm gonna go ahead and bring up the putty session. We'll go through the difference.
01:29
Kind of what each one shows you here.
01:32
So I have
01:34
currently air disabled F A zero to.
01:38
So let's go ahead and just see what show interfaces FAA Zahra to Stannis springs up.
01:45
So shows were air disabled,
01:49
which is good. So here's the difference. We gotta show show I p interface brief.
01:53
All it says for a phaser to is just down and down,
02:00
so get used to using these different commands to show you different things. You know the show, a peon of praise brief is gonna tell you whether it's been in a violation or not.
02:07
Do you know we go through court secure later? I might actually get that.
02:12
Um
02:14
so show interface is a true too.
02:21
So here we can see where this will also see we are air disabled.
02:27
It will say the disease shows air duplexes. We'll get into speed here in just a moment.
02:35
Um,
02:37
well, the one you're gonna wanna know is that you just show interface status that's gonna show your
02:45
instead. It just have very disabled. Just connected. So you notice you have not connected and disabled, so I'm gonna head end.
02:53
Done a shutdown command on F A 06 So here we show disabled. And if we do a show,
03:02
the interface brief,
03:06
this one will say administratively down
03:09
to know the difference is, um
03:12
what, again? This one doesn't show the poor security violation.
03:15
Um, so I'm gonna go ahead and go on to the next slide here.
03:21
So now we're gonna look into some speed and duplex issues. So remember the show interface status? We didn't see the duplex and speed columns.
03:29
If you do the show interface F a zero to it's gonna kind of give you more like a pear grass style. The deep duplexes speed issues, and I'll show you where to look for collisions.
03:38
And then don't forget the defaults for the auto negotiation failure cause
03:43
it could definitely come up in the examine. It will probably come up in real life someone accidentally hard coded a machine or hard coded a port. And then it's just duplex mix. Max. Remember the
03:53
the 10 magadha 100 bag? It's per second. They're gonna default 1/2 duplex, whereas the gig lines or Gig Ethernet is gonna default to full duplex and Cisco switches.
04:03
I'm gonna bring up the party session, and we'll walk through this real quick.
04:08
So let's run a show in her face
04:12
stairs again.
04:14
And we could see we have duplex.
04:17
We're just set on Auto Auto.
04:20
But since these are
04:24
not currently enabled, it's not gonna actually give us a speed.
04:28
So listen what I'm gonna do, I'm just gonna go in and configure would run a no shut if a 06
04:32
wait for it to come up
04:36
and see if it's okay. So it's already configured.
04:41
So you know, I can see Auto Full Auto 100 so it's negotiated to that,
04:46
which is good.
04:47
So we run a show interfaces have a
04:51
a year or two,
04:55
and I'll show you where to look for the auto duplex speed
05:02
And here is the collisions down here in the bottoms. You're gonna look down here,
05:08
uh, find it here. I'm sure you've already seen it, but for the reason I'm not seeing it.
05:14
Oh, here you go.
05:15
Zero collisions and zero late collisions.
05:19
We'll go over the late collisions here in a little bit, but
05:24
these are the counters you're looking for for collisions.
05:28
These could be a lot of times caused by
05:30
duplex issues. If you're running into collisions,
05:33
right,
05:35
All right. So I'm gonna go ahead and minimize party will go on to the layer one problems. So here's where we're going to use the that command like crazy. So runs frames. I didn't meet the minimum of 64 bites that could be caused by collisions. Giants
05:51
frames legend 15 18 bites and put errors. Is the count total off the Ron's Giants? No buffer CRC. All those errors is gonna have a total count of all those CRC is frames that failed the F. C s or frame check sequence
06:09
that could be caused by collisions as well, you know, to come in wrong, it's gonna mess with the hash that it won't have the right frame check sequence. So frames received with an illegal format again caused by collisions and leak collisions is kind of the ones that you're gonna look at this done with a duplex mismatch.
06:28
So late Collision is the one that happens after the 64th bite of the frame has arrived. Her husband transmit. And sorry.
06:34
Collisions usually happen before that 64th pipe.
06:40
So I will bring up that point decision again. We'll just go through that same thing
06:44
so we can have the runs. Giants, CRC,
06:48
Um,
06:50
where is
06:56
zero frame?
07:00
Um,
07:00
collisions like collisions through all these different ones.
07:05
I don't just
07:08
run these commands on your own switch. See what they look like. See what the different commands air. You know? See what? See what each one pulls up. See what information you can see from each command.
07:17
It's the best would alert him. Um,
07:19
so we're gonna go ahead and moved into the post assessment here.
07:24
What is the Cisco default for an auto negotiation failure for an interface speed of one gigabits per second,
07:30
I have a few seconds.
07:33
It is full duplex,
07:38
and the next episode we're gonna be going over kind of the foreign. Look back at the fording, Roger the switches and kind of go through the whole process off. Now we can look at, you know at what stage where we can start trouble shooting.
07:51
There's always a few guys have questions. Need help. Feel free to shoot the message. Otherwise, thank you for watching this video before two senior next water.

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