1 00:00:00,920 --> 00:00:05,150 In the last section we finally applied our first deployment to our local cluster. 2 00:00:05,180 --> 00:00:10,130 Now just to make sure that everything is working the way we expect or want to try to connect to the 3 00:00:10,520 --> 00:00:14,870 container inside of that pod running the multi client image. 4 00:00:15,050 --> 00:00:19,880 And when we connect to it we should see that little re-act application appear on the screen. 5 00:00:19,880 --> 00:00:24,580 So I want you very quickly to remember how we connect to our local cluster. 6 00:00:24,620 --> 00:00:26,220 We do not use localhost. 7 00:00:26,300 --> 00:00:31,000 We have to run that mini cube IP command. 8 00:00:31,280 --> 00:00:37,330 Remember that mini cube virtual machine that is our local node has its own IP completely different from 9 00:00:37,390 --> 00:00:38,580 localhost. 10 00:00:38,650 --> 00:00:44,350 So we need to first run many cube IP once we get the IP address we'll then make sure that we connect 11 00:00:44,350 --> 00:00:52,170 to the port those associated with that service that we created which was hardcoded to be 3 1 5 1 5. 12 00:00:52,210 --> 00:00:57,660 So back at my terminal I'll do mini cube IP there is the IP of my virtual machine. 13 00:00:57,770 --> 00:01:06,230 I'll copy it or make a new tab inside my browser and then I'll put on Colan 3 1 5 1 5 because again 14 00:01:06,230 --> 00:01:09,500 that is the hard coded port of our service. 15 00:01:09,500 --> 00:01:14,570 And when I do so I do in fact successfully see my application appear on the screen. 16 00:01:14,570 --> 00:01:16,030 Awesome. 17 00:01:16,040 --> 00:01:20,540 Now this is actually going to be a really good time to start to understand why we use these service 18 00:01:20,540 --> 00:01:23,690 things like why do we have to create that service object. 19 00:01:23,690 --> 00:01:28,990 Why were we not able before to just directly connect to one of our pods that was running the container 20 00:01:29,000 --> 00:01:30,140 that we care about. 21 00:01:30,470 --> 00:01:35,120 Well now that we understand the idea behind deployments understanding why we have to how these service 22 00:01:35,120 --> 00:01:37,940 things is going to make a lot more sense. 23 00:01:37,940 --> 00:01:44,020 So one thing I want to show you very quickly back over at your terminal try running the command cube 24 00:01:44,020 --> 00:01:52,050 see T.L. get pods and then we're going to add on an argument here of dash so wide like so that's going 25 00:01:52,050 --> 00:01:56,990 to still get our list of pods but it's going to depend on a little bit of additional information. 26 00:01:57,000 --> 00:02:00,930 Now I'm going to zoom out here really quickly just so I can see a thing on a single line. 27 00:02:00,930 --> 00:02:02,480 There we go. 28 00:02:02,490 --> 00:02:07,570 Now I want you to notice how we now have these IP and note columns over on the right hand side. 29 00:02:07,590 --> 00:02:12,300 Now the really important column to take notice of here is the IP column. 30 00:02:12,600 --> 00:02:17,950 Every single pod that we create gets its own IP address assigned to it. 31 00:02:18,210 --> 00:02:22,640 So we just deployed our deployment just two seconds ago and that created a pod. 32 00:02:22,650 --> 00:02:27,810 It was randomly assigned an IP address of 1 7 2 1 7 0 6. 33 00:02:27,810 --> 00:02:32,610 This is an IP address that is internal to our virtual machine. 34 00:02:32,730 --> 00:02:37,400 So you and I cannot visit that IP or at least we cannot visit it very easily. 35 00:02:37,440 --> 00:02:42,560 It is an IP address that has been assigned to the pod inside of our node right here. 36 00:02:43,730 --> 00:02:49,460 Now the interesting thing about that is that if this POD ever gets deleted or if an additional one is 37 00:02:49,460 --> 00:02:56,270 created or for any reason the pod gets updated or changed in any way shape or form whatsoever it's entirely 38 00:02:56,270 --> 00:03:01,340 possible that the pod might suddenly get a brand new IP address. 39 00:03:01,340 --> 00:03:07,280 So let's imagine that this pod right here has that IP address of something like I know though 1 7 2 40 00:03:07,500 --> 00:03:09,050 0 0 0 0 1. 41 00:03:09,050 --> 00:03:11,690 We'll just kind of make up an IP address like so. 42 00:03:12,050 --> 00:03:17,750 So I want you to imagine if we figured out some way to connect our browser to a pod running directly 43 00:03:17,780 --> 00:03:25,100 inside of our node then inside of our browser we would type in something like 1 7 2 0 0 1 and then we 44 00:03:25,100 --> 00:03:26,920 would probably want to connect to port 3000. 45 00:03:26,920 --> 00:03:30,820 So we'd probably put on Colin 3000 or something like that. 46 00:03:30,830 --> 00:03:37,010 Now the problem starts to arise if we start to recreate this pod right here because maybe we have to 47 00:03:37,280 --> 00:03:42,500 remake it because our configuration has changed on the deployment or maybe the original pod crash or 48 00:03:42,620 --> 00:03:45,000 whatever reason it might be. 49 00:03:45,110 --> 00:03:51,950 And so we can imagine that maybe we have to create a second pod and this one would get a randomly generated 50 00:03:51,970 --> 00:03:58,500 IP of something like 0 0 or 2 and then maybe this original pod gets deleted. 51 00:03:58,750 --> 00:04:05,170 Well now we originally had an IP address of 1 7 2 0 0 1 that IP addresses are not going to work anymore 52 00:04:05,320 --> 00:04:11,360 because the object or the pod associate with it just plain no longer exists. 53 00:04:11,380 --> 00:04:17,740 And so in order to access this pod right here we would in theory now have to manually type in that 00 54 00:04:17,740 --> 00:04:19,270 to like so. 55 00:04:19,300 --> 00:04:24,310 Now as you might guess having to update the IP address all the time inside your browser in a development 56 00:04:24,310 --> 00:04:30,590 environment would definitely be a big pain and that's why we make use of these service objects. 57 00:04:30,610 --> 00:04:36,820 The service is going to watch for every pod that matches its selector because remember that service 58 00:04:36,820 --> 00:04:38,180 has a selector. 59 00:04:38,290 --> 00:04:45,020 If we look at client no ports e-mail it has the selector of component where so the service is going 60 00:04:45,020 --> 00:04:51,490 to look for every pod with that selector and then automatically route traffic directly over to it. 61 00:04:51,500 --> 00:04:55,980 So that's why we make use of the service these pods are coming and going all the time. 62 00:04:56,090 --> 00:05:01,280 They're getting deleted they're getting recreated and every time they potentially might get assigned 63 00:05:01,340 --> 00:05:07,040 a brand new IP address the service is going to kind of abstract out that difficulty and that's why we 64 00:05:07,040 --> 00:05:08,430 make use of these services. 65 00:05:08,510 --> 00:05:11,880 And each time that we want to connect to one of our different pots. 66 00:05:12,260 --> 00:05:12,500 OK. 67 00:05:12,500 --> 00:05:15,620 So hopefully that gives you a better idea of why we care about these service things. 68 00:05:15,620 --> 00:05:18,850 So let's take a quick pause right here and we'll continue in the next section.