WEBVTT 00:00.690 --> 00:01.523 Narrator: In the last section, 00:01.523 --> 00:03.060 we had a quick discussion around the differences 00:03.060 --> 00:06.330 between Ingress-NGINX and Kubernetes ingress. 00:06.330 --> 00:08.190 We're now going to continue and start to talk 00:08.190 --> 00:10.110 about how this ingress stuff works 00:10.110 --> 00:12.120 behind the scenes to somehow get some amount 00:12.120 --> 00:13.890 of traffic into your application. 00:13.890 --> 00:15.660 So, let's get to it. 00:15.660 --> 00:18.300 Now, I wanna first begin by giving you a quick reminder 00:18.300 --> 00:19.560 of how we've been doing things 00:19.560 --> 00:21.660 throughout this entire course. 00:21.660 --> 00:24.180 Throughout the entire course, we've been making config 00:24.180 --> 00:28.020 files that contain the desired state of our application. 00:28.020 --> 00:30.780 So for example, we've been writing config files that say 00:30.780 --> 00:34.680 that we want to be running three pods or three replicas, 00:34.680 --> 00:37.560 each of which run the multi-client image. 00:37.560 --> 00:39.690 We then feed that into kubectl 00:39.690 --> 00:42.390 and that creates a deployment object, and it's up 00:42.390 --> 00:46.020 to that deployment object to look at our current state 00:46.020 --> 00:48.240 and then look at our desired state and figure 00:48.240 --> 00:50.820 out some migration path or some way to get 00:50.820 --> 00:53.280 from the current state to the desired state. 00:53.280 --> 00:55.020 And so after the deployment jumps 00:55.020 --> 00:57.000 into effect and starts working, 00:57.000 --> 00:59.850 it's going to eventually create three new pods 00:59.850 --> 01:02.343 each of which are running the multi-client image. 01:03.180 --> 01:05.310 Now, the reason I'm giving you this reminder 01:05.310 --> 01:07.020 about how all this stuff works is 01:07.020 --> 01:09.750 that this deployment object right here is what 01:09.750 --> 01:12.510 we're referred to as a type of controller. 01:12.510 --> 01:15.750 In Kubernetes, a controller is any type of object 01:15.750 --> 01:18.930 that constantly works to make some desired state 01:18.930 --> 01:21.780 a reality inside of our cluster. 01:21.780 --> 01:24.480 So in the world of ingresses, and as we start to talk 01:24.480 --> 01:27.420 about ingress, the exact same strategy right 01:27.420 --> 01:30.750 here all applies a hundred percent. 01:30.750 --> 01:33.480 You and I are going to write some config file 01:33.480 --> 01:35.880 that describes a set of routing rules 01:35.880 --> 01:38.190 to take incoming traffic and send it 01:38.190 --> 01:41.790 off to the appropriate services inside of our cluster. 01:41.790 --> 01:45.210 We're then going to feed that config file into kubectl 01:45.210 --> 01:47.460 And kubectl is going to create something called 01:47.460 --> 01:49.710 an ingress controller. 01:49.710 --> 01:52.320 So it is a controller, it is something that's going to look 01:52.320 --> 01:55.770 at our current state, it's gonna look at the desired state 01:55.770 --> 01:58.290 and then create some infrastructure that's going to 01:58.290 --> 02:00.630 make our desired state a reality. 02:00.630 --> 02:04.170 So in the case of our particular ingress controller 02:04.170 --> 02:07.410 which is, as you might guess, using NGINX behind the scenes, 02:07.410 --> 02:10.470 when we feed in this config file, the controller is going 02:10.470 --> 02:13.680 to create a pod running NGINX that's gonna have 02:13.680 --> 02:16.260 a very particular set of rules to make sure 02:16.260 --> 02:18.330 that traffic comes in and gets sent off 02:18.330 --> 02:21.990 to the appropriate different services inside of our cluster. 02:21.990 --> 02:23.820 So you can kind of think that this entire setup 02:23.820 --> 02:27.030 around ingress looks a little something like this. 02:27.030 --> 02:29.130 We have our ingress config over here, 02:29.130 --> 02:31.110 which is our config file that describes 02:31.110 --> 02:32.880 all the routing rules that we want 02:32.880 --> 02:34.580 to have inside of our application. 02:35.430 --> 02:37.890 That's going to be fed into kubectl, 02:37.890 --> 02:39.900 where an ingress controller is going to 02:39.900 --> 02:42.690 be constantly working behind the scenes to make sure 02:42.690 --> 02:45.030 that all of the routing rules that we define 02:45.030 --> 02:48.840 inside the ingress config are actually implemented and met. 02:48.840 --> 02:51.060 And so it's going to be up to the ingress controller 02:51.060 --> 02:54.630 to create something, something you know, 02:54.630 --> 02:56.310 who knows what it is, but something 02:56.310 --> 02:59.400 inside of our cluster that will take the incoming traffic, 02:59.400 --> 03:01.710 read some parameters in that traffic, 03:01.710 --> 03:04.560 and then send it off to the appropriate service. 03:04.560 --> 03:06.300 So the big takeaway right here, the only thing 03:06.300 --> 03:08.280 I want you to understand right now is that you 03:08.280 --> 03:11.250 and I are gonna create something called an ingress config 03:11.250 --> 03:14.100 which is going to be a set of routing rules. 03:14.100 --> 03:16.200 We're going to feed it into kubectl 03:16.200 --> 03:18.600 which is going to create this ingress controller. 03:18.600 --> 03:21.390 And the ingresses controller's job is to look 03:21.390 --> 03:23.040 at the ingress config or that set 03:23.040 --> 03:25.950 of routing rules and make that a reality. 03:25.950 --> 03:28.680 The ingress controller has to create some infrastructure 03:28.680 --> 03:30.510 inside of our cluster to make sure 03:30.510 --> 03:33.810 that we're actually obeying those routing rules. 03:33.810 --> 03:36.090 And so the ingress controller is going to make, again, 03:36.090 --> 03:38.793 some thing that accepts incoming traffic. 03:39.930 --> 03:42.120 Okay, so that's the kind of high level description 03:42.120 --> 03:43.530 of what's going on here. 03:43.530 --> 03:46.530 Now, in the case of the project that we are using, 03:46.530 --> 03:49.530 Ingress-NGINX, things are going to work very similar 03:49.530 --> 03:52.830 to this but just a tiny, tiny, tiny bit differently. 03:52.830 --> 03:55.290 And so infinitesimally differently, differently 03:55.290 --> 03:57.270 that I almost don't even want to tell you 03:57.270 --> 03:58.500 that it's working differently. 03:58.500 --> 04:00.300 But I am anyways just so you understand 04:00.300 --> 04:02.340 how things are working behind the scenes. 04:02.340 --> 04:04.680 So with the very particular project that we are using 04:04.680 --> 04:07.680 of Ingress-NGINX, the ingress controller 04:07.680 --> 04:10.560 and the thing that actually accepts traffic and routes it 04:10.560 --> 04:14.280 off to the appropriate location is actually the same thing. 04:14.280 --> 04:17.460 So with the very particular ingress project 04:17.460 --> 04:19.530 that we are using, the ingress controller 04:19.530 --> 04:22.130 and the thing that routes traffic is the same thing. 04:22.980 --> 04:24.570 So we can kind of imagine, again, that you 04:24.570 --> 04:26.520 and I are going to make a ingress config 04:26.520 --> 04:27.960 or a set of routing rules. 04:27.960 --> 04:30.330 We're gonna feed it into kubectl 04:30.330 --> 04:32.010 and then the project that we are using, 04:32.010 --> 04:35.700 Ingress-NGINX, is gonna create a single deployment, 04:35.700 --> 04:38.970 whose job is to both read in the ingress config 04:38.970 --> 04:42.930 and simultaneously create a pod that meets all 04:42.930 --> 04:44.640 of those different routing rules. 04:44.640 --> 04:47.730 Now again, this is a very tiny, tiny, tiny distinction 04:47.730 --> 04:50.310 and I only mention this to you because we are going to look 04:50.310 --> 04:52.050 at some of the behind the scenes setup 04:52.050 --> 04:54.300 of Ingress-NGINX inside of our project. 04:54.300 --> 04:55.980 And you're going to notice that there are not 04:55.980 --> 04:58.740 like the three separate things that I show you right here. 04:58.740 --> 05:01.380 In our project, there's only the two separate things 05:01.380 --> 05:03.690 as shown in this diagram right here. 05:03.690 --> 05:06.000 Okay, so with that in mind, let's take a quick pause. 05:06.000 --> 05:07.230 We're gonna come back to the next section 05:07.230 --> 05:08.760 and there's just a little bit more 05:08.760 --> 05:11.190 around some behind the scenes action 05:11.190 --> 05:13.020 for this ingress stuff that I wanna show you 05:13.020 --> 05:14.430 before we start going through the setup. 05:14.430 --> 05:17.080 So quick break and I'll talk to you in just a minute.