1
00:00:00,340 --> 00:00:01,320
Okay, so in this lecture,

2
00:00:01,320 --> 00:00:02,827
we're going to create a Classic Load Balancer.

3
00:00:02,827 --> 00:00:05,260
But to do so first, let's launch an instance.

4
00:00:05,260 --> 00:00:07,110
Very quickly, just the way we've done it before.

5
00:00:07,110 --> 00:00:08,780
we'll choose Amazon Linux 2,

6
00:00:08,780 --> 00:00:12,740
a t2 micro and we'll configure it to have the web server

7
00:00:12,740 --> 00:00:13,573
as we had from before.

8
00:00:13,573 --> 00:00:16,740
So, if we go in here, copy the entire script

9
00:00:16,740 --> 00:00:18,460
and paste it entirely,

10
00:00:18,460 --> 00:00:19,860
then Add Storage.

11
00:00:19,860 --> 00:00:20,900
Everything looks good.

12
00:00:20,900 --> 00:00:22,240
Add Tags, Security Group.

13
00:00:22,240 --> 00:00:24,880
We will use the existing security group here from before.

14
00:00:24,880 --> 00:00:26,680
So, launch-wizard-1

15
00:00:26,680 --> 00:00:28,780
and click on Review and Launch, and Launch.

16
00:00:28,780 --> 00:00:31,448
We're going to create our EC2 Instance.

17
00:00:31,448 --> 00:00:33,810
And this EC2 Instance right here

18
00:00:33,810 --> 00:00:34,960
is going to have a web server.

19
00:00:34,960 --> 00:00:38,690
So, I will keep this in here while it starts.

20
00:00:38,690 --> 00:00:41,930
And the left hand side, I'm gonna go into Load Balancers.

21
00:00:41,930 --> 00:00:44,270
So, I am in the Load Balancer consoles

22
00:00:44,270 --> 00:00:45,800
and I will create my first Load Balancer.

23
00:00:45,800 --> 00:00:47,750
So, I have four options available to me.

24
00:00:47,750 --> 00:00:50,464
There is Application Load Balancer, Network Load Balancer,

25
00:00:50,464 --> 00:00:54,030
Gateway Load Balancer and Classic Load Balancer.

26
00:00:54,030 --> 00:00:55,597
So, as we can see the Classic

27
00:00:55,597 --> 00:00:57,940
is sort of deprecated as Previous Generation.

28
00:00:57,940 --> 00:00:59,180
So, we can still create it,

29
00:00:59,180 --> 00:01:02,130
but it's discouraged by areas to use it.

30
00:01:02,130 --> 00:01:05,730
We'll see ALD and NLB in the next lectures

31
00:01:05,730 --> 00:01:09,080
and Gateway Load Balancer for now is out of scope.

32
00:01:09,080 --> 00:01:12,870
So, let's click and create a Classic Load Balancer.

33
00:01:12,870 --> 00:01:16,080
I'll call it my-demo-clb.

34
00:01:16,080 --> 00:01:18,550
We'll create inside of My Default VPC

35
00:01:18,550 --> 00:01:20,470
and we can make this an internal load balancer

36
00:01:20,470 --> 00:01:21,530
if you wanted to keep it private.

37
00:01:21,530 --> 00:01:23,050
But we want to access it from our computer.

38
00:01:23,050 --> 00:01:25,820
So, we will leave this unticked

39
00:01:25,820 --> 00:01:26,830
and we will also leave

40
00:01:26,830 --> 00:01:29,040
the advanced VPC configuration unticked.

41
00:01:29,040 --> 00:01:31,110
So, in term of Listener Configuration,

42
00:01:31,110 --> 00:01:32,840
we want our Classical Load Balancer

43
00:01:32,840 --> 00:01:35,860
to be welcoming HTTP traffic onto it.

44
00:01:35,860 --> 00:01:37,644
So, that means that HTTP on port 80

45
00:01:37,644 --> 00:01:39,227
is what we want to allow.

46
00:01:39,227 --> 00:01:43,550
And then, it's going to go to the EC2 instances on port 80

47
00:01:43,550 --> 00:01:44,970
for the protocol HTTP as well.

48
00:01:44,970 --> 00:01:46,740
So, this is great.

49
00:01:46,740 --> 00:01:48,200
Next, for security group.

50
00:01:48,200 --> 00:01:50,210
We're going to create a new security group

51
00:01:50,210 --> 00:01:51,641
for our Classic Load Balancer

52
00:01:51,641 --> 00:01:56,641
and I will call it my-first-load-balancer-sg,

53
00:01:58,310 --> 00:02:00,810
and then we can just leave the description as is.

54
00:02:00,810 --> 00:02:03,310
And so, we're going to have to allow

55
00:02:03,310 --> 00:02:05,120
HTTP traffic from anywhere.

56
00:02:05,120 --> 00:02:08,780
So, HTTP on port 80, from and this is anywhere

57
00:02:08,780 --> 00:02:10,449
as long as it's IPV4

58
00:02:10,449 --> 00:02:13,660
and we can do anywhere to have IPV4 and IPV6 as well

59
00:02:13,660 --> 00:02:15,500
which is not supported by the classical Balancer.

60
00:02:15,500 --> 00:02:18,810
Therefore, you don't see IPV6 in here.

61
00:02:18,810 --> 00:02:20,160
Okay, so we're good to go.

62
00:02:20,160 --> 00:02:23,400
So next, we can configure the security settings.

63
00:02:23,400 --> 00:02:24,600
And right now, we get a warning

64
00:02:24,600 --> 00:02:26,850
because we're not using HTTPS or SSL,

65
00:02:26,850 --> 00:02:28,900
but this is fine because right now in this sector,

66
00:02:28,900 --> 00:02:31,780
we don't want to encrypt traffic in flights.

67
00:02:31,780 --> 00:02:32,950
Next for health checks,

68
00:02:32,950 --> 00:02:35,570
we need to look at what is going to be checked

69
00:02:35,570 --> 00:02:36,403
on our instance.

70
00:02:36,403 --> 00:02:37,236
As you can see, the health check

71
00:02:37,236 --> 00:02:39,580
is going to talk to EC2 Instances

72
00:02:39,580 --> 00:02:42,890
on the protocol HTTP, the port 80,

73
00:02:42,890 --> 00:02:45,850
and the path is going to be /index-html.

74
00:02:45,850 --> 00:02:47,430
So, let's ensure that it works.

75
00:02:47,430 --> 00:02:49,166
So, let's take this public IPV4.

76
00:02:49,166 --> 00:02:51,786
I'm going to copy the IP and open it.

77
00:02:51,786 --> 00:02:54,520
And so, as you can see, we get the Hello World.

78
00:02:54,520 --> 00:02:56,470
But what if we add the path?

79
00:02:56,470 --> 00:02:59,770
So, /index.html onto here?

80
00:02:59,770 --> 00:03:02,670
So, if you press enter, we still get the same URL.

81
00:03:02,670 --> 00:03:04,940
So, this Ping Path would work.

82
00:03:04,940 --> 00:03:06,780
The /Ping Path would work as well.

83
00:03:06,780 --> 00:03:08,220
So, I'd like you to just have a slash.

84
00:03:08,220 --> 00:03:10,380
But it should do like /foobar.

85
00:03:10,380 --> 00:03:12,240
For example, for something that doesn't exist

86
00:03:12,240 --> 00:03:14,910
we do like /foobar and press enter.

87
00:03:14,910 --> 00:03:16,000
We're going to get an error.

88
00:03:16,000 --> 00:03:18,125
And this error would make our instance unhealthy

89
00:03:18,125 --> 00:03:20,610
if we kept the health check as /foorbar.

90
00:03:20,610 --> 00:03:22,450
So, we wanna keep it to a path that we know works

91
00:03:22,450 --> 00:03:24,400
for example, just as slash.

92
00:03:24,400 --> 00:03:26,870
And if we have justice slash, then we get just a URL

93
00:03:26,870 --> 00:03:29,330
and we get the Hello World back from our EC2 Instance.

94
00:03:29,330 --> 00:03:31,020
So, this is perfect.

95
00:03:31,020 --> 00:03:32,480
In terms of the health check,

96
00:03:32,480 --> 00:03:33,470
we need to configure a timeout.

97
00:03:33,470 --> 00:03:34,770
So, five second is great.

98
00:03:34,770 --> 00:03:36,520
How often we want to do the health checks.

99
00:03:36,520 --> 00:03:38,625
So, let's keep it at three seconds.

100
00:03:38,625 --> 00:03:41,420
How many times instance needs to be unhealthy?

101
00:03:41,420 --> 00:03:42,550
So, let's do it five.

102
00:03:42,550 --> 00:03:44,050
Then, for it to be happy.

103
00:03:44,050 --> 00:03:45,740
How many times do unhealthy counts

104
00:03:45,740 --> 00:03:47,480
should be before the instant should be unhealthy.

105
00:03:47,480 --> 00:03:48,560
So, two is great.

106
00:03:48,560 --> 00:03:50,321
And how many times the health checks should be correct

107
00:03:50,321 --> 00:03:52,490
until the instance is deemed healthy?

108
00:03:52,490 --> 00:03:54,630
Let's keep it to a low number like three.

109
00:03:54,630 --> 00:03:56,430
So that means that, once three health checks pass,

110
00:03:56,430 --> 00:03:57,630
then instances are healthy.

111
00:03:57,630 --> 00:03:59,730
And if two health checks in a row don't pass,

112
00:03:59,730 --> 00:04:01,710
then it's unhealthy.

113
00:04:01,710 --> 00:04:04,100
Okay, next we'll need you to add EC2 Instances.

114
00:04:04,100 --> 00:04:07,090
I'm going to add this EC2 Instance

115
00:04:07,090 --> 00:04:11,880
and then I will Add Tags, Create and Create.

116
00:04:11,880 --> 00:04:15,250
So, our first Classic Load Balancer is created

117
00:04:15,250 --> 00:04:16,220
and actually the HealthCheck timeout

118
00:04:16,220 --> 00:04:17,180
must be less than interval.

119
00:04:17,180 --> 00:04:18,470
So, let's review and resolve.

120
00:04:18,470 --> 00:04:22,350
So, the response time out must be less study interval.

121
00:04:22,350 --> 00:04:25,440
So, let's keep the response amount to five seconds,

122
00:04:25,440 --> 00:04:27,853
four seconds and then create it again.

123
00:04:29,050 --> 00:04:29,883
And we're good to go.

124
00:04:29,883 --> 00:04:32,580
So, my Classical Load Balancer was successfully created.

125
00:04:32,580 --> 00:04:35,650
So, here as our Classic Load Balancer

126
00:04:35,650 --> 00:04:37,500
and we need to wait for it to come up.

127
00:04:37,500 --> 00:04:39,230
So, let me pause and get back to you

128
00:04:39,230 --> 00:04:41,180
when it is up and running.

129
00:04:41,180 --> 00:04:42,620
If we check the video right now as you can see,

130
00:04:42,620 --> 00:04:44,070
the Instance is out of service

131
00:04:44,070 --> 00:04:45,700
and if you go over the info, it says,

132
00:04:45,700 --> 00:04:47,470
Instance registration is still in progress.

133
00:04:47,470 --> 00:04:49,340
So if you see out of service for your instance,

134
00:04:49,340 --> 00:04:50,670
please wait a little bit

135
00:04:50,670 --> 00:04:51,590
before asking the Q&A.

136
00:04:51,590 --> 00:04:54,050
Then it gets to in-service.

137
00:04:54,050 --> 00:04:56,090
So, that means that's our Classical Balancer is working.

138
00:04:56,090 --> 00:04:59,060
Now, if you don't get in-service

139
00:04:59,060 --> 00:05:00,670
in say a minute or two minutes,

140
00:05:00,670 --> 00:05:03,140
then I will show you what may be going wrong.

141
00:05:03,140 --> 00:05:05,650
So right now, let's assume that everything is working.

142
00:05:05,650 --> 00:05:08,060
Please don't ask a question in the Q&A just yet.

143
00:05:08,060 --> 00:05:10,990
So, we're going to open the URL DNS name

144
00:05:10,990 --> 00:05:12,120
our Classical Balancer.

145
00:05:12,120 --> 00:05:13,120
And as you can see,

146
00:05:13,120 --> 00:05:16,080
we get Hello World from the EC2 Instance.

147
00:05:16,080 --> 00:05:19,410
The same as if we had used the public facing IP.

148
00:05:19,410 --> 00:05:22,620
So that means that the Classic Load Balancer is working.

149
00:05:22,620 --> 00:05:24,240
But, what if it didn't work?

150
00:05:24,240 --> 00:05:27,480
What if we had an instance that was unhealthy?

151
00:05:27,480 --> 00:05:29,250
So, may be your Instance is unhealthy

152
00:05:29,250 --> 00:05:30,690
because of security groups.

153
00:05:30,690 --> 00:05:33,860
So, if we go into the security groups right now

154
00:05:33,860 --> 00:05:35,810
and go to launch-wizard-1

155
00:05:35,810 --> 00:05:37,800
and let's say we want to remove

156
00:05:37,800 --> 00:05:39,160
these HTTP rules right here.

157
00:05:39,160 --> 00:05:42,790
So, I'm going to delete these HTTP rules and save the rule.

158
00:05:42,790 --> 00:05:44,230
This will make so that...

159
00:05:44,230 --> 00:05:47,210
Well, this Instance right here is not accessible

160
00:05:47,210 --> 00:05:50,500
from the public internet of course,

161
00:05:50,500 --> 00:05:53,340
but also from the privates, it was internet because

162
00:05:53,340 --> 00:05:57,110
well, there's no port 80 available on the security group.

163
00:05:57,110 --> 00:05:59,840
So that means that, for example, in this example,

164
00:05:59,840 --> 00:06:01,347
well, my Instance should be marked

165
00:06:01,347 --> 00:06:02,770
OutOfService very quickly.

166
00:06:02,770 --> 00:06:04,890
And so, right now, I see it is out of service.

167
00:06:04,890 --> 00:06:06,020
So, this could be one reason

168
00:06:06,020 --> 00:06:07,820
why the instance is out of service.

169
00:06:07,820 --> 00:06:10,140
And the other reason why it could be out of service

170
00:06:10,140 --> 00:06:12,210
is that the Hello World just doesn't work

171
00:06:12,210 --> 00:06:14,810
and the bootstrap script did not execute properly.

172
00:06:14,810 --> 00:06:17,820
So, these are the two reasons why this would not work.

173
00:06:17,820 --> 00:06:20,440
Okay. So, let's go back into our instance.

174
00:06:20,440 --> 00:06:23,560
When we had the inbound rule to be HTTP

175
00:06:24,900 --> 00:06:28,470
on port 80 from anywhere on the IPV4

176
00:06:28,470 --> 00:06:30,050
and save the rule.

177
00:06:30,050 --> 00:06:31,230
So when we had this,

178
00:06:31,230 --> 00:06:32,430
we can access our instance

179
00:06:32,430 --> 00:06:35,770
both from the public IP and from the Classical Balancer

180
00:06:35,770 --> 00:06:36,700
which is not working right now,

181
00:06:36,700 --> 00:06:38,860
because I need to wait for my instance

182
00:06:38,860 --> 00:06:40,850
to go back in service

183
00:06:40,850 --> 00:06:42,440
which should take about 15 seconds.

184
00:06:42,440 --> 00:06:43,860
So, that was back in service.

185
00:06:43,860 --> 00:06:45,200
I refresh this and it works.

186
00:06:45,200 --> 00:06:46,530
Okay, so the problem is that

187
00:06:46,530 --> 00:06:48,580
we can access our EC2 Instances directly

188
00:06:48,580 --> 00:06:49,870
and also, through the Load Balancer.

189
00:06:49,870 --> 00:06:52,690
But we would like to tighten the security.

190
00:06:52,690 --> 00:06:54,560
This is where we can show something really cool

191
00:06:54,560 --> 00:06:55,620
with security groups.

192
00:06:55,620 --> 00:06:57,550
We can change the inbound rule

193
00:06:57,550 --> 00:07:00,040
to only allow HTTP rule on port 80,

194
00:07:00,040 --> 00:07:01,380
but not from anywhere.

195
00:07:01,380 --> 00:07:04,850
And instead, we want to allow it from a security group

196
00:07:04,850 --> 00:07:06,360
of the Load Balancer.

197
00:07:06,360 --> 00:07:08,330
So, my first Load Balancer.

198
00:07:08,330 --> 00:07:10,780
So, we are allowing any traffic

199
00:07:10,780 --> 00:07:13,070
from the security group of the Load Balancer

200
00:07:13,070 --> 00:07:15,840
into the security group of the EC2 Instances.

201
00:07:15,840 --> 00:07:18,930
So, allow only traffic

202
00:07:18,930 --> 00:07:21,080
from the ELB.

203
00:07:21,080 --> 00:07:24,210
And the reason we do so is that we want the ELB

204
00:07:24,210 --> 00:07:26,070
to access our instance, okay?

205
00:07:26,070 --> 00:07:27,960
But we don't want our users

206
00:07:27,960 --> 00:07:30,620
to directly access our instances as you can see now.

207
00:07:30,620 --> 00:07:34,590
If I refer to this page, I get an endless running cycle.

208
00:07:34,590 --> 00:07:36,430
And in here, if I refresh,

209
00:07:36,430 --> 00:07:37,480
well, it still works.

210
00:07:37,480 --> 00:07:40,150
So, we can access our EC2 Instances only now,

211
00:07:40,150 --> 00:07:41,297
through the Load Balancer.

212
00:07:41,297 --> 00:07:43,200
So, we have enhanced the security

213
00:07:43,200 --> 00:07:46,670
and that is a very, very common pattern in AWS.

214
00:07:46,670 --> 00:07:49,090
So finally, let's show the whole power of Load Balancing

215
00:07:49,090 --> 00:07:50,760
by having more instances.

216
00:07:50,760 --> 00:07:51,930
So, I can ran click

217
00:07:51,930 --> 00:07:54,300
and say Launch instance from this templates.

218
00:07:54,300 --> 00:07:55,950
For example, oops!

219
00:07:55,950 --> 00:07:59,460
Right click and say Launch instances

220
00:07:59,460 --> 00:08:00,890
and then use the one.

221
00:08:00,890 --> 00:08:03,160
So, we'll use t2 micro

222
00:08:03,160 --> 00:08:05,800
and for instance details, we're good to go.

223
00:08:05,800 --> 00:08:08,500
We can also provide the user data

224
00:08:08,500 --> 00:08:09,710
just like we had from before.

225
00:08:09,710 --> 00:08:11,950
So, let's provide it

226
00:08:11,950 --> 00:08:13,690
and Add Storage,

227
00:08:13,690 --> 00:08:16,560
Add Tags, Security Group, Review and Launch.

228
00:08:16,560 --> 00:08:20,900
So, we will pass in the launch-wizard-1 security group.

229
00:08:20,900 --> 00:08:23,203
Launch, and yes, we have the key pair.

230
00:08:24,280 --> 00:08:26,940
That's one of them and we can do another one like this.

231
00:08:26,940 --> 00:08:30,160
So, we will launch an instance again.

232
00:08:30,160 --> 00:08:32,919
Select, we have t2 micro.

233
00:08:32,919 --> 00:08:34,650
I'm trying to go a little bit fast here.

234
00:08:34,650 --> 00:08:36,299
Paste the users data.

235
00:08:36,299 --> 00:08:37,610
Storage is good.

236
00:08:37,610 --> 00:08:40,679
Security Group, we're going to do launch- wizard-1,

237
00:08:40,679 --> 00:08:43,513
Review and Launch, and Launch, okay.

238
00:08:44,650 --> 00:08:45,810
So, the effect of this is that

239
00:08:45,810 --> 00:08:48,620
now we have three EC2 Instances that are launched

240
00:08:48,620 --> 00:08:52,440
and they will all have their own Hello Hello World message.

241
00:08:52,440 --> 00:08:53,350
And so, what I want to do

242
00:08:53,350 --> 00:08:55,140
is to (indistinct) these instances

243
00:08:55,140 --> 00:08:56,590
on to my Classical Balancer.

244
00:08:56,590 --> 00:08:58,680
So, I go to my Classical Balancer,

245
00:08:58,680 --> 00:08:59,950
I edit my instances

246
00:08:59,950 --> 00:09:02,870
and now I add these two new instances.

247
00:09:02,870 --> 00:09:04,890
So now, we have three instances

248
00:09:04,890 --> 00:09:07,440
registered on my Classical balancer

249
00:09:07,440 --> 00:09:09,020
and as you can see, two are OutOfService

250
00:09:09,020 --> 00:09:11,190
because they're still booting up.

251
00:09:11,190 --> 00:09:12,550
So, what's going to happen

252
00:09:12,550 --> 00:09:14,520
is that we need to use our data script

253
00:09:14,520 --> 00:09:17,140
on the EC2 Instances to complete successfully.

254
00:09:17,140 --> 00:09:19,220
And then, once the EC2 Instances are up,

255
00:09:19,220 --> 00:09:21,830
they should be put in service by our Load balancer.

256
00:09:21,830 --> 00:09:23,530
And again, if you see OutOfService,

257
00:09:23,530 --> 00:09:26,640
this maybe because you don't have

258
00:09:26,640 --> 00:09:28,350
the user data script run properly

259
00:09:28,350 --> 00:09:29,560
or some security group issues.

260
00:09:29,560 --> 00:09:32,050
But if you see some inservice and some OutOfService,

261
00:09:32,050 --> 00:09:33,530
and they have the same security groups,

262
00:09:33,530 --> 00:09:36,320
then it's not a security group issue, okay?

263
00:09:36,320 --> 00:09:39,570
So, let's just switch a little bit for this to complete.

264
00:09:39,570 --> 00:09:41,810
Okay, so my three instances are in service

265
00:09:41,810 --> 00:09:43,680
and they're spread across two availability zones.

266
00:09:43,680 --> 00:09:46,980
So, us-east-2a and us-east-2c.

267
00:09:46,980 --> 00:09:48,910
And so now, if I go back to my load balancer

268
00:09:48,910 --> 00:09:49,978
and refresh the page,

269
00:09:49,978 --> 00:09:51,350
every time I refresh,

270
00:09:51,350 --> 00:09:54,730
I'm going to get a new EC2 Instance replying to me

271
00:09:54,730 --> 00:09:56,430
and therefore we get a new Hello World message

272
00:09:56,430 --> 00:09:58,340
from a different private IP.

273
00:09:58,340 --> 00:10:00,840
So, this shows that every time I refresh the browser,

274
00:10:00,840 --> 00:10:04,130
my request goes to a different EC2 Instance

275
00:10:04,130 --> 00:10:06,150
and that means that my load balancer indeed

276
00:10:06,150 --> 00:10:08,340
is load balancing my requests.

277
00:10:08,340 --> 00:10:09,550
So, this is pretty cool.

278
00:10:09,550 --> 00:10:12,220
And that concludes the demo for the Load Balancers.

279
00:10:12,220 --> 00:10:13,070
So, that's it for this demo.

280
00:10:13,070 --> 00:10:15,020
Please delete the Classical Balancer.

281
00:10:15,020 --> 00:10:16,310
We will not be using it.

282
00:10:16,310 --> 00:10:18,990
But keep the EC2 Instances running during the section

283
00:10:18,990 --> 00:10:20,730
as we'll be creating new Load Balancers

284
00:10:20,730 --> 00:10:22,010
and using them as well.

285
00:10:22,010 --> 00:10:22,843
So, that's it.

286
00:10:22,843 --> 00:10:24,430
I will see you in the next lecture.