1
00:00:02,577 --> 00:00:05,494
(electronic music)

2
00:00:08,583 --> 00:00:10,286
- So at this point, you
should hopefully feel

3
00:00:10,286 --> 00:00:12,439
pretty comfortable with adding routers,

4
00:00:12,439 --> 00:00:14,718
and switches, and frame relay switches

5
00:00:14,718 --> 00:00:17,761
into your topology,
into your GNS3 network.

6
00:00:17,761 --> 00:00:18,627
So, you might be getting to the point

7
00:00:18,627 --> 00:00:19,836
where you say, you know what?

8
00:00:19,836 --> 00:00:22,509
I'd really like to add
a host into my network.

9
00:00:22,509 --> 00:00:24,529
I'd like to have a host
for a variety of reasons.

10
00:00:24,529 --> 00:00:26,000
Maybe to ping back and forth,

11
00:00:26,000 --> 00:00:28,319
or to do some other types of testing.

12
00:00:28,319 --> 00:00:29,727
Now, let's step back here for a second.

13
00:00:29,727 --> 00:00:32,319
You might wonder, well
Keith, why do I need a host?

14
00:00:32,319 --> 00:00:35,136
I mean, if I just wanted to do ping tests,

15
00:00:35,136 --> 00:00:37,530
or if I want to generate some,

16
00:00:37,530 --> 00:00:40,216
just test access lists
or something like that,

17
00:00:40,216 --> 00:00:41,927
can't I just plug in another router

18
00:00:41,927 --> 00:00:43,516
and ping from the other router?

19
00:00:43,516 --> 00:00:44,465
Well certainly, you can do that.

20
00:00:44,465 --> 00:00:46,108
But keep in mind one thing.

21
00:00:46,108 --> 00:00:48,297
Anytime you plug a
router into your topology

22
00:00:48,297 --> 00:00:50,946
and then you start it, you're consuming

23
00:00:50,946 --> 00:00:52,911
another instance of router memory.

24
00:00:52,911 --> 00:00:55,398
If that software that
that router's running

25
00:00:55,398 --> 00:00:57,860
takes 500 megabits per second,

26
00:00:57,860 --> 00:01:00,277
let's say it's a 7200 series router,

27
00:01:00,277 --> 00:01:02,456
now you're just eating up a lot more RAM

28
00:01:02,456 --> 00:01:05,176
in your laptop simply to have some device

29
00:01:05,176 --> 00:01:07,059
that you can ping from.

30
00:01:07,059 --> 00:01:09,040
So for here, for something like that

31
00:01:09,040 --> 00:01:10,542
and a lot of other useful reasons,

32
00:01:10,542 --> 00:01:12,920
I'd like to talk about the VPCS,

33
00:01:12,920 --> 00:01:16,049
the Virtual PC Simulator that's included

34
00:01:16,049 --> 00:01:19,466
as yet another built in node within GNS3.

35
00:01:20,488 --> 00:01:22,464
Now, I've been using this quite a bit

36
00:01:22,464 --> 00:01:24,158
throughout the various topologies,

37
00:01:24,158 --> 00:01:25,505
and I've been promising you, well,

38
00:01:25,505 --> 00:01:26,631
I'll get to it, I'll get to it.

39
00:01:26,631 --> 00:01:28,433
Well now is our time to talk about it.

40
00:01:28,433 --> 00:01:29,728
So, let's talk about it a little bit.

41
00:01:29,728 --> 00:01:33,757
So first of all, this
particular node is available

42
00:01:33,757 --> 00:01:37,983
right here in the Browse
End Devices section.

43
00:01:37,983 --> 00:01:39,471
So, that's where you would find this.

44
00:01:39,471 --> 00:01:40,971
So, click on that,

45
00:01:42,242 --> 00:01:45,387
and then we're gonna be using VPCS.

46
00:01:45,387 --> 00:01:47,124
So, you just drag and drop it on just

47
00:01:47,124 --> 00:01:48,506
like you normally would.

48
00:01:48,506 --> 00:01:52,050
Now these, unlike your
built in Ethernet switches

49
00:01:52,050 --> 00:01:54,777
and your built in frame
relay switch and everything,

50
00:01:54,777 --> 00:01:57,462
these you can turn on and turn off.

51
00:01:57,462 --> 00:02:00,180
And notice that bu
default, is deactivated.

52
00:02:00,180 --> 00:02:01,581
It's turned off.

53
00:02:01,581 --> 00:02:05,300
So, let me get rid of this one here.

54
00:02:05,300 --> 00:02:07,182
So, I've already go three instances

55
00:02:07,182 --> 00:02:10,042
of my Virtual PCs in
this particular topology.

56
00:02:10,042 --> 00:02:13,858
And, I wanna show you some of
the real power behind this.

57
00:02:13,858 --> 00:02:17,266
For example, let's start
out with PC number two here.

58
00:02:17,266 --> 00:02:19,337
And in this particular
PC, I just wanna give

59
00:02:19,337 --> 00:02:22,020
it a static IP address and mask,

60
00:02:22,020 --> 00:02:23,970
and a static default gateway.

61
00:02:23,970 --> 00:02:25,077
Real easy to do that.

62
00:02:25,077 --> 00:02:28,233
So, just go ahead and
double-click on it to open it up,

63
00:02:28,233 --> 00:02:30,129
and this is what your console
window will look like.

64
00:02:30,129 --> 00:02:32,269
It actually has a pretty
intuitive Help menu,

65
00:02:32,269 --> 00:02:33,202
and I like it a lot.

66
00:02:33,202 --> 00:02:35,466
I just type, for example,
the question mark,

67
00:02:35,466 --> 00:02:37,724
and you can see all the different options

68
00:02:37,724 --> 00:02:39,627
are available to you here.

69
00:02:39,627 --> 00:02:40,867
So in my particular case, I'll say,

70
00:02:40,867 --> 00:02:43,556
well, I wanna add a static IP address.

71
00:02:43,556 --> 00:02:44,906
Well, we can see from here that

72
00:02:44,906 --> 00:02:46,243
IP is probably what I want to do.

73
00:02:46,243 --> 00:02:48,346
IP what, what should I do?

74
00:02:48,346 --> 00:02:50,343
IP and you can actually see,
it gives you an example.

75
00:02:50,343 --> 00:02:54,510
IP, the address, the mask,
and then the default gateway.

76
00:02:55,831 --> 00:02:57,635
So, my particular case if I want this guy

77
00:02:57,635 --> 00:03:01,802
to be 4.4.4.1, I would
just type IP 4.4.4.1/24,

78
00:03:04,884 --> 00:03:08,674
and then this default gateway is 4.4.4.2.

79
00:03:08,674 --> 00:03:10,257
So you can see, it's a
little bit of a different

80
00:03:10,257 --> 00:03:13,941
syntax than typing an IP
address on a router's interface,

81
00:03:13,941 --> 00:03:16,248
where you actually type IP address.

82
00:03:16,248 --> 00:03:18,356
Here, you just type, as you can see.

83
00:03:18,356 --> 00:03:19,339
Now, there's one.

84
00:03:19,339 --> 00:03:22,044
Before I go any further with VPCS,

85
00:03:22,044 --> 00:03:25,235
one very important thing
you have to remember.

86
00:03:25,235 --> 00:03:26,928
Let's think about routers for a second.

87
00:03:26,928 --> 00:03:29,632
If you make a change in
your router's configuration,

88
00:03:29,632 --> 00:03:33,058
you're making a change in the
running configuration, right?

89
00:03:33,058 --> 00:03:35,616
So, what happens if you stop that router,

90
00:03:35,616 --> 00:03:37,419
and you haven't saved those configs,

91
00:03:37,419 --> 00:03:40,239
or you completely stop your project.

92
00:03:40,239 --> 00:03:41,955
Anything in your running config that has

93
00:03:41,955 --> 00:03:43,752
not been saved, is gone.

94
00:03:43,752 --> 00:03:44,599
It's wiped out.

95
00:03:44,599 --> 00:03:46,690
So that's why, as hopefully
by this point in time

96
00:03:46,690 --> 00:03:48,776
you know, with routers,
you should always issue

97
00:03:48,776 --> 00:03:51,671
the right memory command
or the Copy, Run, Start

98
00:03:51,671 --> 00:03:53,632
command after you make changes.

99
00:03:53,632 --> 00:03:56,639
Well in a similar way, these Virtual PCs,

100
00:03:56,639 --> 00:03:58,491
when you make a change
so their configuration,

101
00:03:58,491 --> 00:04:01,777
like I just did here, you have to save it.

102
00:04:01,777 --> 00:04:04,228
If you don't, the moment you turn off that

103
00:04:04,228 --> 00:04:08,096
Virtual PC or the moment you
exit from your GNS3 project,

104
00:04:08,096 --> 00:04:10,871
whatever you configured
your Virtual PC for,

105
00:04:10,871 --> 00:04:12,261
his settings will be gone.

106
00:04:12,261 --> 00:04:13,240
It'll vanish.

107
00:04:13,240 --> 00:04:15,112
So, how do we save his settings?

108
00:04:15,112 --> 00:04:18,334
It's simply the save command.

109
00:04:18,334 --> 00:04:19,270
And, that's all you have to do.

110
00:04:19,270 --> 00:04:22,306
So, remember that with
your Virtual PC to issue

111
00:04:22,306 --> 00:04:24,522
the save command whenever
you make a change.

112
00:04:24,522 --> 00:04:27,756
So, that's a way of configuring
a static IP Address,

113
00:04:27,756 --> 00:04:29,708
mask, and default gateway.

114
00:04:29,708 --> 00:04:32,867
What about over here, PC number one?

115
00:04:32,867 --> 00:04:35,812
I wanna configure him as a DHCP client.

116
00:04:35,812 --> 00:04:37,277
Well, this is another powerful thing

117
00:04:37,277 --> 00:04:39,772
we can do here within VPCS.

118
00:04:39,772 --> 00:04:42,522
So I'll just double-click on him,

119
00:04:43,539 --> 00:04:45,706
so I'm on PC one, and now,

120
00:04:46,923 --> 00:04:49,923
if I do ip ?, I can just do ip dhcp.

121
00:04:52,443 --> 00:04:54,565
That's all I have to do.

122
00:04:54,565 --> 00:04:57,517
Now, there are some options if you wish.

123
00:04:57,517 --> 00:05:01,807
But if you just do ip dhcp,
the moment you type that,

124
00:05:01,807 --> 00:05:05,378
it will send out a DHCP
discover message and attempt

125
00:05:05,378 --> 00:05:07,734
to get an IP address.

126
00:05:07,734 --> 00:05:10,208
Now, this guy already has an IP address,

127
00:05:10,208 --> 00:05:11,680
as you can see, 1.1.1.4.

128
00:05:11,680 --> 00:05:14,026
So, let's see actually
how this works in action.

129
00:05:14,026 --> 00:05:16,420
So number one, let's try
releasing that address

130
00:05:16,420 --> 00:05:17,584
and getting a new one.

131
00:05:17,584 --> 00:05:20,592
So ip dhcp, and it says right here,

132
00:05:20,592 --> 00:05:24,092
- r, actually -x is to
release the address.

133
00:05:25,109 --> 00:05:25,942
So, -x.

134
00:05:27,184 --> 00:05:30,425
Sho ip, okay so now we
have nothing, right.

135
00:05:30,425 --> 00:05:33,420
So, -x was to release the
address and now it's gone.

136
00:05:33,420 --> 00:05:37,468
Still remember the DNS
settings and the DHCP server,

137
00:05:37,468 --> 00:05:39,289
but the address is gone.

138
00:05:39,289 --> 00:05:40,153
So, how do I get a new one?

139
00:05:40,153 --> 00:05:41,236
Just ip dhcp.

140
00:05:43,589 --> 00:05:45,231
I'll explain to you in just a moment

141
00:05:45,231 --> 00:05:47,231
what these letters mean.

142
00:05:48,154 --> 00:05:48,987
And, there we go.

143
00:05:48,987 --> 00:05:52,004
So, what did those letters
mean that I was looking at?

144
00:05:52,004 --> 00:05:56,473
This is actually showing
you the DHCP decode.

145
00:05:56,473 --> 00:06:00,851
This is the discover, and then
you sent another discover,

146
00:06:00,851 --> 00:06:04,277
and then he received a
DHCP offer, then the client

147
00:06:04,277 --> 00:06:07,796
sent out a DHCP request,
and the transaction

148
00:06:07,796 --> 00:06:12,167
was finished by receiving
a DHCP acknowledgement.

149
00:06:12,167 --> 00:06:13,212
And what's kinda nice is you can drill

150
00:06:13,212 --> 00:06:14,962
down even further than that.

151
00:06:14,962 --> 00:06:18,187
If I do ip dhcp ?, you'll see

152
00:06:18,187 --> 00:06:22,423
I can also do -d to actually
get a packet decode.

153
00:06:22,423 --> 00:06:24,779
So, let's try that, ip dhcp.

154
00:06:24,779 --> 00:06:28,268
I want to release my address in -d.

155
00:06:28,268 --> 00:06:30,304
I want to see the decode of it.

156
00:06:30,304 --> 00:06:31,698
And there we go, see?

157
00:06:31,698 --> 00:06:34,602
So, he sent out a DHCP Option 53,

158
00:06:34,602 --> 00:06:36,850
which is a release message.

159
00:06:36,850 --> 00:06:39,884
And now, I can do ip dhcp -d

160
00:06:39,884 --> 00:06:43,043
to actually watch the
whole process in action.

161
00:06:43,043 --> 00:06:46,384
So now, he's sending out requests.

162
00:06:46,384 --> 00:06:49,528
There's the reply, and then we're done.

163
00:06:49,528 --> 00:06:52,195
So, let's go up to the top here.

164
00:06:54,411 --> 00:06:58,328
Okay, so the first message
was a DHCP Discover.

165
00:06:59,426 --> 00:07:02,951
Then he sent out another Discover.

166
00:07:02,951 --> 00:07:04,564
And then, we received back the Offer,

167
00:07:04,564 --> 00:07:05,887
and we can see all the information

168
00:07:05,887 --> 00:07:08,848
that was included in that offer.

169
00:07:08,848 --> 00:07:11,326
Then, we sent out a DHCP Request.

170
00:07:11,326 --> 00:07:12,785
And the final step in the process was

171
00:07:12,785 --> 00:07:16,952
a DHCP server sent back to
us, a DHCP acknowledgement.

172
00:07:17,912 --> 00:07:20,267
So, the -d option is very useful in this

173
00:07:20,267 --> 00:07:23,119
particular case as far
as DHCP is concerned,

174
00:07:23,119 --> 00:07:26,023
if you want to actually
watch the DHCP transaction.

175
00:07:26,023 --> 00:07:28,187
Now, you might be wondering,
now wait a second Keith,

176
00:07:28,187 --> 00:07:31,589
who is the DHCP server in
this particular topology?

177
00:07:31,589 --> 00:07:35,130
Well, as you go through your CCNA studies,

178
00:07:35,130 --> 00:07:36,152
one of the things they're gonna expect

179
00:07:36,152 --> 00:07:40,642
you to know is how to configure
a router as a DHCP server.

180
00:07:40,642 --> 00:07:42,549
I'm not gonna go into the
details of that right now.

181
00:07:42,549 --> 00:07:45,926
I will show you that I've
done that on router two.

182
00:07:45,926 --> 00:07:48,593
If I show you his configuration,

183
00:07:51,830 --> 00:07:53,754
right up here towards that top is

184
00:07:53,754 --> 00:07:55,765
the DHCP configuration configuring this

185
00:07:55,765 --> 00:07:59,193
particular router as the DHCP server.

186
00:07:59,193 --> 00:08:01,864
So, that was already pre-done.

187
00:08:01,864 --> 00:08:04,541
Let's get back to VPCS here for a moment.

188
00:08:04,541 --> 00:08:08,995
So another powerful tool of
VPCS, you can ping from it.

189
00:08:08,995 --> 00:08:12,245
For example, I can ping from PC1 to PC3

190
00:08:13,475 --> 00:08:15,028
to see if my routing and frame relay

191
00:08:15,028 --> 00:08:15,968
and everything is set up.

192
00:08:15,968 --> 00:08:19,135
So, let's see if PC1 can ping 5.5.5.1.

193
00:08:21,283 --> 00:08:23,116
Let's see if it works.

194
00:08:29,126 --> 00:08:31,468
We're getting a time out,

195
00:08:31,468 --> 00:08:34,862
and then the ping is successful.

196
00:08:34,862 --> 00:08:36,736
Now you might be thinking,
okay Keith, but big deal.

197
00:08:36,736 --> 00:08:39,493
I mean, I can ping from a router.

198
00:08:39,493 --> 00:08:41,392
Why use this Virtual PC?

199
00:08:41,392 --> 00:08:44,549
Well, the Virtual PC for
one thing uses a lot less

200
00:08:44,549 --> 00:08:47,480
memory than another router instance does.

201
00:08:47,480 --> 00:08:49,200
So yes, you could have put a router

202
00:08:49,200 --> 00:08:51,869
into your topology and
had that router set up as

203
00:08:51,869 --> 00:08:54,959
a DHCP client, and watched
the DHCP transaction.

204
00:08:54,959 --> 00:08:56,559
Sure you could have done that.

205
00:08:56,559 --> 00:08:59,095
Sure you could ping from
a router and watch that

206
00:08:59,095 --> 00:09:00,959
and test your access lists and stuff.

207
00:09:00,959 --> 00:09:02,928
But remember, that router is using up

208
00:09:02,928 --> 00:09:07,274
a lot more memory in
your laptop than VPCS is.

209
00:09:07,274 --> 00:09:09,309
And, there's things you can do from here

210
00:09:09,309 --> 00:09:12,349
within VCPS that you
can't do within a router.

211
00:09:12,349 --> 00:09:16,663
For example, look what
happens when I type pin ?.

212
00:09:16,663 --> 00:09:18,246
I can do UDP pings.

213
00:09:19,246 --> 00:09:21,538
I can do TCP pings.

214
00:09:21,538 --> 00:09:23,955
I can set any, if I'm doing a TCP ping,

215
00:09:23,955 --> 00:09:27,669
I can set any of the flags
within the Tcp header.

216
00:09:27,669 --> 00:09:29,421
What if I'm testing quality of service,

217
00:09:29,421 --> 00:09:31,054
and I need to have a packet generator.

218
00:09:31,054 --> 00:09:33,926
I wanna see if my quality
of service policers,

219
00:09:33,926 --> 00:09:37,080
or our markers or stuff
are working correctly.

220
00:09:37,080 --> 00:09:39,339
Well, how would you
create a packet generator

221
00:09:39,339 --> 00:09:41,049
out of a Syscall Router?

222
00:09:41,049 --> 00:09:42,555
It would be kinda hard to do.

223
00:09:42,555 --> 00:09:44,148
A ping's not gonna do it.

224
00:09:44,148 --> 00:09:48,082
But here with VPCS, I could ping via UDP,

225
00:09:48,082 --> 00:09:50,968
and do it like every five seconds.

226
00:09:50,968 --> 00:09:52,926
And then, I could use the -t option

227
00:09:52,926 --> 00:09:55,160
to say, just keep going.

228
00:09:55,160 --> 00:09:56,660
For example, ping.

229
00:09:58,585 --> 00:09:59,719
Who do I want to ping?

230
00:09:59,719 --> 00:10:00,552
5.5.5.1.

231
00:10:01,502 --> 00:10:05,669
Now, I wanna do -2, because
I want to be in UDP mode,

232
00:10:06,606 --> 00:10:09,510
and then I wanna do
-i, and I'll have those

233
00:10:09,510 --> 00:10:13,343
pings go out every 10
milliseconds, that's -i.

234
00:10:15,369 --> 00:10:17,429
And then, I'm gonna do -t.

235
00:10:17,429 --> 00:10:20,929
Keep those pings going, until I stop them.

236
00:10:21,889 --> 00:10:23,992
And, there they go.

237
00:10:23,992 --> 00:10:25,472
Now, let's keep running
with them for a moment.

238
00:10:25,472 --> 00:10:27,020
I'll just keep letting them go.

239
00:10:27,020 --> 00:10:30,983
Now if I go over my router, router two,

240
00:10:30,983 --> 00:10:32,239
on router two, let's go ahead and check

241
00:10:32,239 --> 00:10:34,727
out those that are going
through him right now,

242
00:10:34,727 --> 00:10:36,781
and they should be coming
in Fast Ethernet 0/0

243
00:10:36,781 --> 00:10:40,091
and going out Serial 2/0.

244
00:10:40,091 --> 00:10:42,261
So if I had some sort
of policer or something

245
00:10:42,261 --> 00:10:44,562
else like that configured
for quality of service,

246
00:10:44,562 --> 00:10:47,610
maybe I applied it to Serial 2/0.

247
00:10:47,610 --> 00:10:50,065
Let's see what the actual
output rate is right now,

248
00:10:50,065 --> 00:10:55,019
considering massive UPD pings
are leaving on that interface.

249
00:10:55,019 --> 00:10:56,754
All right, so let's go to router two.

250
00:10:56,754 --> 00:10:59,004
Sho int ser 2/0.

251
00:11:02,484 --> 00:11:04,436
We can see that right now, the output rate

252
00:11:04,436 --> 00:11:07,201
is about 16,000 bits per second.

253
00:11:07,201 --> 00:11:09,768
Now, I tried this before
I did this recording

254
00:11:09,768 --> 00:11:13,257
and if you wait, oh about
five or six minutes,

255
00:11:13,257 --> 00:11:16,395
this will get up, not too far.

256
00:11:16,395 --> 00:11:19,079
It'll go, I waited for
about three or four minutes

257
00:11:19,079 --> 00:11:22,367
and it got up to about
64,000 bits per second.

258
00:11:22,367 --> 00:11:25,051
But as far as just QOS
testing is concerned,

259
00:11:25,051 --> 00:11:26,132
that's fine, right?

260
00:11:26,132 --> 00:11:27,686
If you just wanna create a simple policer

261
00:11:27,686 --> 00:11:31,437
and try to police this down
to three kilobits per second

262
00:11:31,437 --> 00:11:33,975
or eight kilobits per
second, you could do that.

263
00:11:33,975 --> 00:11:36,566
But in order to test a
policer, you have to have

264
00:11:36,566 --> 00:11:38,902
some traffic coming in to police it.

265
00:11:38,902 --> 00:11:42,090
So, this VPCS can be used
to generate that traffic.

266
00:11:42,090 --> 00:11:44,407
But, we're not done yet.

267
00:11:44,407 --> 00:11:46,907
So, let me go back to my VPCS.

268
00:11:48,483 --> 00:11:51,163
Control C, break out of it.

269
00:11:51,163 --> 00:11:53,846
For you aspiring CCNA candidates,

270
00:11:53,846 --> 00:11:56,343
you're gonna be learning
about Cisco access lists.

271
00:11:56,343 --> 00:11:57,804
How do you test your access lists?

272
00:11:57,804 --> 00:12:00,155
Well certainly, you can create simple

273
00:12:00,155 --> 00:12:03,571
access lists like blocking
telnet or blocking ping,

274
00:12:03,571 --> 00:12:05,605
because telnet and ping
traffic is stuff you

275
00:12:05,605 --> 00:12:07,378
can source from a router, right?

276
00:12:07,378 --> 00:12:09,403
You can jump onto a router,
and from that router,

277
00:12:09,403 --> 00:12:11,332
you can type ping or telnet,

278
00:12:11,332 --> 00:12:13,172
and then see if your access list works.

279
00:12:13,172 --> 00:12:14,476
But if you want, what
if you want to create

280
00:12:14,476 --> 00:12:17,317
some more complex access
lists that are maybe

281
00:12:17,317 --> 00:12:21,384
blocking or permitting certain
TCP ports or UDP ports.

282
00:12:21,384 --> 00:12:23,761
In that case, how would
you generate the traffic

283
00:12:23,761 --> 00:12:25,883
to actually test that access list?

284
00:12:25,883 --> 00:12:29,554
You could do it from
right here within VPCS.

285
00:12:29,554 --> 00:12:33,246
As an example, on router four here,

286
00:12:33,246 --> 00:12:35,077
I have created an outbound access list

287
00:12:35,077 --> 00:12:37,149
of Fast Ethernet 0/0.

288
00:12:37,149 --> 00:12:38,935
And, that outbound
access list is permitting

289
00:12:38,935 --> 00:12:41,935
all traffic except UDP traffic going

290
00:12:42,977 --> 00:12:45,894
to port number 99 as a destination.

291
00:12:47,067 --> 00:12:47,900
Sh run.

292
00:12:50,389 --> 00:12:52,844
So you can see here, I
applied the access list.

293
00:12:52,844 --> 00:12:55,254
There's the access group outbound.

294
00:12:55,254 --> 00:12:57,837
And if I go to access list 101,

295
00:13:00,049 --> 00:13:01,843
here is that access list.

296
00:13:01,843 --> 00:13:05,074
Denying all UDP traffic
from the 1.1.1 network

297
00:13:05,074 --> 00:13:08,402
to the 5.5.5 network
if the destination UPD

298
00:13:08,402 --> 00:13:12,696
port number is 99, and then
permitting everything else.

299
00:13:12,696 --> 00:13:14,660
So, how would I test that?

300
00:13:14,660 --> 00:13:17,243
Well, let's go back to my VPCS.

301
00:13:18,553 --> 00:13:19,470
So, ping ?.

302
00:13:20,731 --> 00:13:23,844
All right, so why don't
we do ping 5.5.5.1,

303
00:13:23,844 --> 00:13:28,011
that's the remote PC, and
why don't we do -2 for UDP,

304
00:13:29,666 --> 00:13:31,291
and then let's do -p.

305
00:13:31,291 --> 00:13:33,229
And notice, it's a lowercase p here.

306
00:13:33,229 --> 00:13:36,193
Very important that you
select the lowercase p

307
00:13:36,193 --> 00:13:37,480
for the port number, as opposed to

308
00:13:37,480 --> 00:13:40,076
the uppercase P for protocol, which is

309
00:13:40,076 --> 00:13:43,078
the IP protocol in the IP header.

310
00:13:43,078 --> 00:13:46,346
So, I'm gonna do -p, and
let's start out with the port

311
00:13:46,346 --> 00:13:47,864
number that should be okay.

312
00:13:47,864 --> 00:13:51,127
The access list should allow UDP pings

313
00:13:51,127 --> 00:13:53,747
going to destination port 90.

314
00:13:53,747 --> 00:13:55,427
Might get a timeout for one or two of 'em,

315
00:13:55,427 --> 00:13:56,286
but then they should work.

316
00:13:56,286 --> 00:13:58,166
There we go, so now, they're working.

317
00:13:58,166 --> 00:14:00,092
Now, let's test to see
if the access list works.

318
00:14:00,092 --> 00:14:03,282
Let's change that destination
port number to 99.

319
00:14:03,282 --> 00:14:06,352
The access list is supposed to drop that.

320
00:14:06,352 --> 00:14:07,386
And, it is.

321
00:14:07,386 --> 00:14:10,742
We're getting communication
administratively prohibited.

322
00:14:10,742 --> 00:14:14,508
So, this is a great way to
also test your access lists.

323
00:14:14,508 --> 00:14:16,850
There's a lot of other things
this can do here as well.

324
00:14:16,850 --> 00:14:19,351
One other thing I wanna show
you, which is really neat.

325
00:14:19,351 --> 00:14:22,768
If you just do set ?, you'll see that one

326
00:14:24,885 --> 00:14:28,052
of the options is the set dump option.

327
00:14:29,678 --> 00:14:32,011
So, you can do set dump all,

328
00:14:35,044 --> 00:14:38,219
and what this does,
it's actually like doing

329
00:14:38,219 --> 00:14:41,585
a debug packet all on a router.

330
00:14:41,585 --> 00:14:43,944
This basically says now,
any packet that this

331
00:14:43,944 --> 00:14:46,568
PC sends out, whether it be a UDP ping,

332
00:14:46,568 --> 00:14:50,141
a TCP ping, whatever,
I wanna see all of it.

333
00:14:50,141 --> 00:14:54,308
So for example, let's do that
same UDP ping I just did.

334
00:14:55,556 --> 00:14:58,626
See now, we get a lot
more information about it.

335
00:14:58,626 --> 00:15:02,980
We see the 3.3.3.2, so
that's the actual address

336
00:15:02,980 --> 00:15:06,076
of the router that has
the access list on it.

337
00:15:06,076 --> 00:15:08,976
We see the time-to-live,
we see milliseconds,

338
00:15:08,976 --> 00:15:10,989
we see the ICMP type code.

339
00:15:10,989 --> 00:15:12,881
Okay, this isn't that big of a deal.

340
00:15:12,881 --> 00:15:14,578
But, look at the real power of this.

341
00:15:14,578 --> 00:15:17,016
What if I want to test out TCP?

342
00:15:17,016 --> 00:15:18,508
Maybe, you just learned about TCP

343
00:15:18,508 --> 00:15:19,536
and you wanna see, okay, I've learned

344
00:15:19,536 --> 00:15:21,803
there's this TCP three way handshake.

345
00:15:21,803 --> 00:15:24,362
I've learned a little
bit about the TCP flags.

346
00:15:24,362 --> 00:15:27,278
So, I wanna see some of
that stuff in action.

347
00:15:27,278 --> 00:15:29,695
Well, we can do this, ping ?.

348
00:15:31,345 --> 00:15:33,178
Let's do ping 5.5.5.1.

349
00:15:34,184 --> 00:15:38,612
Now remember, we still have
the set dump all configured.

350
00:15:38,612 --> 00:15:41,083
Right, that didn't stop, right there.

351
00:15:41,083 --> 00:15:42,675
Set dump all.

352
00:15:42,675 --> 00:15:46,840
It's sort of like a debug
all in the world of VPCS.

353
00:15:46,840 --> 00:15:49,299
So, we'll do ping 5.5.5.1.

354
00:15:49,299 --> 00:15:51,382
Let's do -3 for TCP mode,

355
00:15:53,247 --> 00:15:56,124
and why don't we do a, that's it.

356
00:15:56,124 --> 00:15:57,377
Well, just do that.

357
00:15:57,377 --> 00:15:59,544
But, TPC pings to 5.5.5.1.

358
00:16:07,872 --> 00:16:10,907
Okay, so something is blocking this.

359
00:16:10,907 --> 00:16:12,574
Can we ping 5.5.5.1?

360
00:16:14,320 --> 00:16:15,676
Yeah, we can still ping it.

361
00:16:15,676 --> 00:16:18,009
We just can't do a TCP ping.

362
00:16:20,600 --> 00:16:22,683
Sequence two, 5.5.5.1 -3.

363
00:16:23,851 --> 00:16:28,098
- 3 is supposed to be TCP mode, all right.

364
00:16:28,098 --> 00:16:30,695
Well, let's go over to our routers

365
00:16:30,695 --> 00:16:33,818
real quickly and troubleshoot this.

366
00:16:33,818 --> 00:16:37,985
First of all, let me look at
my access list on router four.

367
00:16:39,394 --> 00:16:41,164
So, I'm denying UDP.

368
00:16:41,164 --> 00:16:43,738
I'm permitting all other IP.

369
00:16:43,738 --> 00:16:45,976
So, that should be all right, okay?

370
00:16:45,976 --> 00:16:49,809
Let's now go over to the
remote PC of 5.5.5.1,

371
00:16:52,062 --> 00:16:57,007
and let's verify that he
actually has an IP address.

372
00:16:57,007 --> 00:17:01,294
And he is 5.5.5.1, and his
default gateway is 5.5.5.2.

373
00:17:01,294 --> 00:17:03,824
All right, that looks good.

374
00:17:03,824 --> 00:17:07,336
So, there's no reason I
can think of at this point

375
00:17:07,336 --> 00:17:10,590
why those TCP pings were not functional.

376
00:17:10,590 --> 00:17:14,463
Let's set the dump to off, set dump off.

377
00:17:14,463 --> 00:17:16,387
That's sort of like an undebug all

378
00:17:16,387 --> 00:17:18,880
in the world of Cisco terminology.

379
00:17:18,880 --> 00:17:19,963
Ping 5.5.5.1.

380
00:17:25,438 --> 00:17:28,188
Okay, well -3 should be TCP mode.

381
00:17:29,736 --> 00:17:31,375
And just like a Cisco router, you can use

382
00:17:31,375 --> 00:17:33,683
the up and down arrows on your keyboard

383
00:17:33,683 --> 00:17:35,938
because it does keep a command history

384
00:17:35,938 --> 00:17:37,146
of what you've done.

385
00:17:37,146 --> 00:17:41,313
Ping 5.5.5.1 -3, and we'll
do a count of three of them.

386
00:17:48,834 --> 00:17:50,434
Okay, so that's working.

387
00:17:50,434 --> 00:17:52,226
All right, so now let's
turn the set dump back on.

388
00:17:52,226 --> 00:17:53,309
Set dump all.

389
00:17:55,816 --> 00:17:58,316
And, let's do that ping again.

390
00:18:08,649 --> 00:18:09,533
Hmm, okay.

391
00:18:09,533 --> 00:18:10,950
Well, set dump ?.

392
00:18:16,599 --> 00:18:19,342
Ah, it's set dump detail.

393
00:18:19,342 --> 00:18:23,239
That's what we're looking
for, set dump detail.

394
00:18:23,239 --> 00:18:26,700
That's like an IP packet detail.

395
00:18:26,700 --> 00:18:30,033
All right, now let's do that ping again.

396
00:18:34,021 --> 00:18:35,524
There we go, that's
what I was looking for,

397
00:18:35,524 --> 00:18:38,398
set dump detail is what
we were looking for.

398
00:18:38,398 --> 00:18:41,027
So, let's go ahead and
after our ping is done here,

399
00:18:41,027 --> 00:18:44,708
which I think it's done, set dump off.

400
00:18:44,708 --> 00:18:47,407
And starting at the top,

401
00:18:47,407 --> 00:18:49,571
we can see the detail we were looking for.

402
00:18:49,571 --> 00:18:52,293
So, let's go all the way to
the top of this TCP stream.

403
00:18:52,293 --> 00:18:55,259
Okay, so here was when I did my TCP ping.

404
00:18:55,259 --> 00:18:59,198
So here we see, source
address, destination address.

405
00:18:59,198 --> 00:19:00,531
Protocol is TCP.

406
00:19:01,396 --> 00:19:03,756
Acknowledgement number,
sequence number, flags.

407
00:19:03,756 --> 00:19:06,524
This is the sync, this is the TCP sync.

408
00:19:06,524 --> 00:19:10,158
Here is the incoming
sync ack, and the ack.

409
00:19:10,158 --> 00:19:12,719
So right here, these three
show me all the details

410
00:19:12,719 --> 00:19:14,947
of my TCP 3 way handshake.

411
00:19:14,947 --> 00:19:18,331
Now, we can see the push
bit and the ack bit are set.

412
00:19:18,331 --> 00:19:19,645
So as you can go through this, you can get

413
00:19:19,645 --> 00:19:21,889
a lot more information
than you normally could

414
00:19:21,889 --> 00:19:26,399
in just a regular debug
IP packet within a router,

415
00:19:26,399 --> 00:19:28,201
using the set dump detail.

416
00:19:28,201 --> 00:19:30,777
And once again, set dump off was the way

417
00:19:30,777 --> 00:19:32,527
that you turn it off.

418
00:19:33,528 --> 00:19:37,404
So, there's a lot more that
you can do with Virtual PCs.

419
00:19:37,404 --> 00:19:41,030
I would encourage you to Google VPCS.

420
00:19:41,030 --> 00:19:43,467
There's a lot of
documentation out there on it.

421
00:19:43,467 --> 00:19:45,695
But hopefully in this
video, I've given you

422
00:19:45,695 --> 00:19:48,362
a good starting point as
far as some good ideas

423
00:19:48,362 --> 00:19:50,825
as to ways you can use this to test

424
00:19:50,825 --> 00:19:54,505
various features and
protocols in your topology.

425
00:19:54,505 --> 00:19:57,422
(electronic music)