WEBVTT 1 00:00:00.420 --> 00:00:01.620 Kamal is a tool for deploying 2 00:00:01.620 --> 00:00:03.510 your web applications anywhere. 3 00:00:03.510 --> 00:00:05.580 Whether you’re deploying to a cloud VM, 4 00:00:05.580 --> 00:00:07.470 or to your own servers, 5 00:00:07.470 --> 00:00:10.860 or to a tiny little pi computer in your closet, 6 00:00:10.860 --> 00:00:12.720 you can use Kamal. 7 00:00:12.720 --> 00:00:16.230 Kamal simply asks that you give it a handful of IP addresses 8 00:00:16.230 --> 00:00:18.240 for the servers you wanna deploy to. 9 00:00:18.240 --> 00:00:20.010 Those servers don’t have to be set up 10 00:00:20.010 --> 00:00:21.600 in any special way in advance. 11 00:00:21.600 --> 00:00:23.460 Kamal will take care of all of that, 12 00:00:23.460 --> 00:00:25.650 including installing Docker, 13 00:00:25.650 --> 00:00:28.350 and that’s exactly what Kamal sits on top of. 14 00:00:28.350 --> 00:00:32.250 It is basically just docker underneath the Kamal controls 15 00:00:32.250 --> 00:00:36.600 to deploy your application to ensure that any updates happen 16 00:00:36.600 --> 00:00:40.470 completely gapless, no 500 errors to be thrown. 17 00:00:40.470 --> 00:00:43.410 It does this by putting a proxy 18 00:00:43.410 --> 00:00:45.600 in front of your applications 19 00:00:45.600 --> 00:00:47.460 as you swap them back and forth. 20 00:00:47.460 --> 00:00:50.100 It all happens without you having to do 21 00:00:50.100 --> 00:00:51.210 pretty much anything about it. 22 00:00:51.210 --> 00:00:54.720 Kamal controls all parts of the equation. 23 00:00:54.720 --> 00:00:59.700 Kamal 2 is now also capable of terminating SSL 24 00:00:59.700 --> 00:01:02.430 and automatically configuring those certificates 25 00:01:02.430 --> 00:01:04.710 using Let’s Encrypt. 26 00:01:04.710 --> 00:01:06.810 You can also deploy multiple applications 27 00:01:06.810 --> 00:01:08.490 on a single server. 28 00:01:08.490 --> 00:01:09.960 And of course you can also deploy 29 00:01:09.960 --> 00:01:11.700 to a bunch of different servers. 30 00:01:11.700 --> 00:01:15.630 That’s what we do at 37signals for all of our deployments, 31 00:01:15.630 --> 00:01:19.080 including things like Hey.com. 32 00:01:19.080 --> 00:01:21.840 And that was where Kamal was originally extracted. 33 00:01:21.840 --> 00:01:24.930 We wanted to move all of our stuff 34 00:01:24.930 --> 00:01:27.360 out of the cloud onto our own servers, 35 00:01:27.360 --> 00:01:30.240 and we created Kamal to do just that. 36 00:01:30.240 --> 00:01:32.880 All of our applications were already running in containers, 37 00:01:32.880 --> 00:01:37.470 so it wasn’t exactly a big leap to deploy them by ourselves 38 00:01:37.470 --> 00:01:39.840 using Kamal, using Docker, 39 00:01:39.840 --> 00:01:42.330 and we felt we didn’t really need anything else 40 00:01:42.330 --> 00:01:45.240 and that many other folks would be in the same boat, 41 00:01:45.240 --> 00:01:47.100 that they would find something like Kubernetes 42 00:01:47.100 --> 00:01:51.300 too complicated or other solutions simply wanting. 43 00:01:51.300 --> 00:01:54.360 We’ve created Kamal exclusively for the purpose 44 00:01:54.360 --> 00:01:58.140 of deploying web applications and keeping them up to date 45 00:01:58.140 --> 00:02:00.300 with as little hassle as possible, 46 00:02:00.300 --> 00:02:02.490 yet still being completely full featured. 47 00:02:02.490 --> 00:02:04.380 We do things like asset bridging 48 00:02:04.380 --> 00:02:06.420 to ensure there’s no 404 errors 49 00:02:06.420 --> 00:02:08.970 as you switch from one version of your application 50 00:02:08.970 --> 00:02:10.290 to the next. 51 00:02:10.290 --> 00:02:12.630 We have accessories that you could use Kamal 52 00:02:12.630 --> 00:02:16.380 to even deploy and control database servers. 53 00:02:16.380 --> 00:02:21.380 Kamal was originally created to work for Rails applications, 54 00:02:21.660 --> 00:02:24.030 but Kamal is really a general purpose tool 55 00:02:24.030 --> 00:02:26.970 that you can use to deploy any type of web application 56 00:02:26.970 --> 00:02:30.480 that can be containerized, which is really all of them. 57 00:02:30.480 --> 00:02:33.480 So I’ll start my example showing you how to do this 58 00:02:33.480 --> 00:02:37.500 with a very basic Hello World Go application. 59 00:02:37.500 --> 00:02:38.433 Let’s get to it. 60 00:02:39.300 --> 00:02:43.110 All right, let’s have a look at a incredibly basic 61 00:02:43.110 --> 00:02:45.510 Go application that simply says Hello World. 62 00:02:45.510 --> 00:02:48.150 This is one of the things I really like about Go. 63 00:02:48.150 --> 00:02:52.680 You can say Hello World in almost no work at all, 64 00:02:52.680 --> 00:02:55.530 and this is what we’re doing here in this single Go file 65 00:02:55.530 --> 00:02:57.510 we have set up in this directory, 66 00:02:57.510 --> 00:03:01.470 starting a server on port 80 and listening to everything, 67 00:03:01.470 --> 00:03:04.500 not just the route but all paths below. 68 00:03:04.500 --> 00:03:05.640 That’s by the way, important. 69 00:03:05.640 --> 00:03:09.330 Make a note of that because Kamal uses /up 70 00:03:09.330 --> 00:03:10.530 as the health check. 71 00:03:10.530 --> 00:03:14.670 So your application must respond 200 okay to /up. 72 00:03:14.670 --> 00:03:15.810 We do it automatically here 73 00:03:15.810 --> 00:03:19.260 because we serve everything on all paths 74 00:03:19.260 --> 00:03:22.380 with the Hello World and 200 Okay. 75 00:03:22.380 --> 00:03:24.390 So that’s a simple application here in Go, 76 00:03:24.390 --> 00:03:27.210 and the Docker file is almost as simple. 77 00:03:27.210 --> 00:03:29.040 It simply has a built stage 78 00:03:29.040 --> 00:03:31.020 that will compile the application, 79 00:03:31.020 --> 00:03:34.890 and then it will copy it into our container On app 80 00:03:34.890 --> 00:03:38.940 exposing port 80 and starting that application 81 00:03:38.940 --> 00:03:40.020 that we just built. 82 00:03:40.020 --> 00:03:43.920 So what we can do is we can start here by 83 00:03:43.920 --> 00:03:46.110 simply building that application 84 00:03:46.110 --> 00:03:49.170 or building the Docker image for that application 85 00:03:49.170 --> 00:03:50.003 we have right here. 86 00:03:50.003 --> 00:03:52.740 I’m calling it Kamago, and we’re just gonna build that. 87 00:03:52.740 --> 00:03:54.210 It goes really quickly. 88 00:03:54.210 --> 00:03:57.900 It is a tiny Docker file, and we are already done. 89 00:03:57.900 --> 00:04:00.510 So now that we’ve built it, we can run it here, 90 00:04:00.510 --> 00:04:03.960 and I am going to map port 80 to 8080, 91 00:04:03.960 --> 00:04:05.610 and then let’s get it running. 92 00:04:05.610 --> 00:04:07.140 If we jump over in the browser here, 93 00:04:07.140 --> 00:04:09.270 and I have a look at 8080, 94 00:04:09.270 --> 00:04:10.950 you can see I’m running my application. 95 00:04:10.950 --> 00:04:12.840 So this is about as simple as it gets, 96 00:04:12.840 --> 00:04:14.610 but this is just enough 97 00:04:14.610 --> 00:04:17.610 and everything we needed to get going with Kamal. 98 00:04:17.610 --> 00:04:18.780 So the first thing we’re gonna do 99 00:04:18.780 --> 00:04:20.640 is we’re gonna do Kamal init, 100 00:04:20.640 --> 00:04:23.460 and that is going to copy over all the configuration files 101 00:04:23.460 --> 00:04:25.320 that we need for the setup, 102 00:04:25.320 --> 00:04:28.890 including a set of lifetime hooks we can look at. 103 00:04:28.890 --> 00:04:31.830 So let’s jump back into Neovim here, 104 00:04:31.830 --> 00:04:34.710 and we will hop into our config, 105 00:04:34.710 --> 00:04:36.600 and you can see there’s a deploy file. 106 00:04:36.600 --> 00:04:38.490 Now this deploy file has a few things 107 00:04:38.490 --> 00:04:40.260 that you need to replace. 108 00:04:40.260 --> 00:04:41.940 One is the name of your service. 109 00:04:41.940 --> 00:04:42.900 We’re gonna call it Kamago. 110 00:04:42.900 --> 00:04:46.500 It uses that to identify the different 111 00:04:46.500 --> 00:04:48.540 containers as they run on your setup. 112 00:04:48.540 --> 00:04:51.480 We will rename it here as well, Kamago. 113 00:04:51.480 --> 00:04:54.480 And then we need to replace my user. 114 00:04:54.480 --> 00:04:57.540 My user is the namespace for the image. 115 00:04:57.540 --> 00:05:00.660 It is also what the register uses to lock in. 116 00:05:00.660 --> 00:05:03.990 So let’s change that to my username. 117 00:05:03.990 --> 00:05:06.570 And we have one more here, down here under the registry. 118 00:05:06.570 --> 00:05:09.150 By default, we are set up to use Docker Hub, 119 00:05:09.150 --> 00:05:11.460 but you can of course use your own registry of any kind 120 00:05:11.460 --> 00:05:16.460 on DigitalOcean, or GitHub, or wherever you want to do it. 121 00:05:16.560 --> 00:05:19.350 Now we’re gonna specify the server we’re gonna deploy to. 122 00:05:19.350 --> 00:05:23.100 And I am going to use my demo server here 123 00:05:23.100 --> 00:05:25.213 that’s running on exitsoftware.io. 124 00:05:26.160 --> 00:05:30.300 And we would like to have SSL set up, yes. 125 00:05:30.300 --> 00:05:32.760 That allows for the auto certifications 126 00:05:32.760 --> 00:05:34.080 through Let’s Encrypt. 127 00:05:34.080 --> 00:05:36.720 And we need a host name for that to work as well. 128 00:05:36.720 --> 00:05:41.460 I have already set up the host name Kamago.exit.io 129 00:05:41.460 --> 00:05:43.620 to point to that demo server. 130 00:05:43.620 --> 00:05:46.680 So we can simply use that and roll off the way. 131 00:05:46.680 --> 00:05:48.630 Now one thing you’ll notice here is that the registry 132 00:05:48.630 --> 00:05:50.610 of course needs a password, 133 00:05:50.610 --> 00:05:55.610 and that password is being plucked out of the secrets. 134 00:05:55.950 --> 00:05:58.470 They’re gonna be here under .Kamal. 135 00:05:58.470 --> 00:06:00.480 And you can see here under Secrets. 136 00:06:00.480 --> 00:06:03.090 We have a bunch of different ways we can get these 137 00:06:03.090 --> 00:06:05.130 secrets to be available to Kamal. 138 00:06:05.130 --> 00:06:07.200 I’m using the very simplest, the default here, 139 00:06:07.200 --> 00:06:11.460 which is simply to pluck it out of the local machine’s ENV, 140 00:06:11.460 --> 00:06:14.310 but you can read straight out of a file, 141 00:06:14.310 --> 00:06:16.410 or you can do what most people will do 142 00:06:16.410 --> 00:06:19.350 and what we do for, for example, deploying Hey, 143 00:06:19.350 --> 00:06:23.700 we set it up with a vault, a secrets vault. 144 00:06:23.700 --> 00:06:26.430 We’re using one password at 37signals. 145 00:06:26.430 --> 00:06:29.700 Here is the setup where you would pluck those 146 00:06:29.700 --> 00:06:31.500 secrets out from a vault, and extract them, 147 00:06:31.500 --> 00:06:34.260 and then assign them to the secrets 148 00:06:34.260 --> 00:06:35.880 that Kamal are gonna use for deploy. 149 00:06:35.880 --> 00:06:38.970 But as I said, we’re just gonna plug it out at the end. 150 00:06:38.970 --> 00:06:40.560 We are going to rely on that, 151 00:06:40.560 --> 00:06:44.670 and we’re building here on an amd64. 152 00:06:44.670 --> 00:06:46.860 That is X86 processor. 153 00:06:46.860 --> 00:06:48.540 That’s what we’re going deploy to. 154 00:06:48.540 --> 00:06:51.510 So this is basically all I need to set up. 155 00:06:51.510 --> 00:06:53.430 So if we save this file, 156 00:06:53.430 --> 00:06:58.430 and we hop back out and do Kamal setup, 157 00:06:59.040 --> 00:07:00.870 it will connect to this server 158 00:07:00.870 --> 00:07:03.990 that is essentially wiped at this stage. 159 00:07:03.990 --> 00:07:06.570 I have a clean demo server for us to use. 160 00:07:06.570 --> 00:07:10.980 It’ll check that Docker is already installed. 161 00:07:10.980 --> 00:07:14.310 Well first, I’m obviously going to connect to it with SSH. 162 00:07:14.310 --> 00:07:15.630 This is, by the way, quite important. 163 00:07:15.630 --> 00:07:16.950 This is the first thing you need to do 164 00:07:16.950 --> 00:07:18.330 when you set up a new server. 165 00:07:18.330 --> 00:07:20.400 You need to exchange SSH keys, 166 00:07:20.400 --> 00:07:22.080 and then turn off password access 167 00:07:22.080 --> 00:07:26.910 such that no one can access your server except by SSH keys. 168 00:07:26.910 --> 00:07:27.743 So. 169 00:07:30.630 --> 00:07:32.010 This is a good point. 170 00:07:32.010 --> 00:07:33.630 I cannot deploy just yet 171 00:07:33.630 --> 00:07:37.080 because we have not committed all of this to Git. 172 00:07:37.080 --> 00:07:39.570 And Git is what we use to get the version 173 00:07:39.570 --> 00:07:41.640 for our application. 174 00:07:41.640 --> 00:07:44.580 So the first thing I’m gonna do is I’m gonna do Git init, 175 00:07:44.580 --> 00:07:47.520 and then I’m gonna do Git add everything, 176 00:07:47.520 --> 00:07:49.830 and then I’m going to commit everything 177 00:07:49.830 --> 00:07:52.170 with the first deploy here. 178 00:07:52.170 --> 00:07:55.710 That will mean that we are now ready to run Kamal’s setup, 179 00:07:55.710 --> 00:07:58.630 and we will actually have 180 00:08:00.720 --> 00:08:03.210 the version, the reference that we can deploy with. 181 00:08:03.210 --> 00:08:05.850 As you can see here, the first thing we do is we build 182 00:08:05.850 --> 00:08:10.200 the image, putting it into a a container image, 183 00:08:10.200 --> 00:08:12.180 and then we push that to Docker Hub. 184 00:08:12.180 --> 00:08:14.160 It goes very quickly, 185 00:08:14.160 --> 00:08:18.600 and then we pull that image down on the remote server. 186 00:08:18.600 --> 00:08:21.120 It’ll pull it off Docker Hub there. 187 00:08:21.120 --> 00:08:23.670 All the setup and exchange of keys is already set up 188 00:08:23.670 --> 00:08:25.890 through those Kamal secrets that we had, 189 00:08:25.890 --> 00:08:28.323 the Kamal registry password. 190 00:08:29.550 --> 00:08:30.780 It’ll start the servers. 191 00:08:30.780 --> 00:08:32.340 It’ll first check if anything is running. 192 00:08:32.340 --> 00:08:33.600 It’ll start the proxy 193 00:08:33.600 --> 00:08:35.970 in case that is not running already as it wasn’t. 194 00:08:35.970 --> 00:08:40.740 And voila, in 39 seconds we have deployed everything. 195 00:08:40.740 --> 00:08:44.940 Let’s go check and see if that is live 196 00:08:44.940 --> 00:08:47.850 at Kamago Exitsoftware.io. 197 00:08:47.850 --> 00:08:49.560 It is, Hello World here. 198 00:08:49.560 --> 00:08:51.330 Everything is working. 199 00:08:51.330 --> 00:08:54.480 If we jump back into our application note, 200 00:08:54.480 --> 00:08:58.800 we could change it here to say Hello World times two, 201 00:08:58.800 --> 00:09:03.210 save that, jump back out, commit an update, 202 00:09:03.210 --> 00:09:06.870 and then we can do Kamal deploy. 203 00:09:06.870 --> 00:09:09.420 Kamal deploy is not gonna do any of the setup activities. 204 00:09:09.420 --> 00:09:12.090 It is simply going to Kamal the changes 205 00:09:12.090 --> 00:09:14.730 that we have to our document, which will go even faster 206 00:09:14.730 --> 00:09:16.770 because now we have all those lovely 207 00:09:16.770 --> 00:09:19.080 layer caches we can lean on. 208 00:09:19.080 --> 00:09:22.410 It will compile it in, what’d it say, six seconds here 209 00:09:22.410 --> 00:09:23.670 to get it all pushed out. 210 00:09:23.670 --> 00:09:26.100 It’ll push it back up to Docker Hub, 211 00:09:26.100 --> 00:09:29.310 pull it onto the new server, and pull it back there. 212 00:09:29.310 --> 00:09:31.170 And then the proxy will do its magic. 213 00:09:31.170 --> 00:09:32.400 If this was a real application 214 00:09:32.400 --> 00:09:34.650 and we had a ton of traffic going into it, 215 00:09:34.650 --> 00:09:38.580 it would first start the new version of the application, 216 00:09:38.580 --> 00:09:40.380 check that that was sound, 217 00:09:40.380 --> 00:09:43.050 and then not switch over until it was making sure 218 00:09:43.050 --> 00:09:45.630 that you would have no dropped connections 219 00:09:45.630 --> 00:09:47.160 in between the two updates. 220 00:09:47.160 --> 00:09:51.480 If we load here, we are running version two, 221 00:09:51.480 --> 00:09:54.123 and that is basically all there is to it. 222 00:09:55.020 --> 00:09:57.210 Now let’s try to make a more substantial demo. 223 00:09:57.210 --> 00:10:00.240 I’m going to create a new Rails 8 application 224 00:10:00.240 --> 00:10:01.080 called Alpha, 225 00:10:01.080 --> 00:10:04.260 and we’re going to run it with the MySQL database. 226 00:10:04.260 --> 00:10:06.330 Normally I would just use SQL Light 227 00:10:06.330 --> 00:10:07.980 if we’re deploying to a single server, 228 00:10:07.980 --> 00:10:10.320 but because we’re going to set this up 229 00:10:10.320 --> 00:10:11.310 with multiple servers, 230 00:10:11.310 --> 00:10:14.340 including an independent database server in this example, 231 00:10:14.340 --> 00:10:17.520 we are going to use MySQL. 232 00:10:17.520 --> 00:10:19.860 But before we get going with the multiple servers, 233 00:10:19.860 --> 00:10:23.280 I’m going to deploy this new application 234 00:10:23.280 --> 00:10:26.640 alongside our Go application on the same server. 235 00:10:26.640 --> 00:10:28.590 That is one of the new things in Kamal 2 236 00:10:28.590 --> 00:10:32.280 that we can deploy to the same server, multiple apps, 237 00:10:32.280 --> 00:10:34.500 and just route it on the host name. 238 00:10:34.500 --> 00:10:36.930 It’s really simple to do. 239 00:10:36.930 --> 00:10:38.730 But this Rails application needs to do something, 240 00:10:38.730 --> 00:10:41.700 and we are going to give it a scaffold interface. 241 00:10:41.700 --> 00:10:42.990 This is the same scaffold interface 242 00:10:42.990 --> 00:10:44.220 I’ve done about a million times. 243 00:10:44.220 --> 00:10:48.900 It’s gonna have a post with a title and a body that is text. 244 00:10:48.900 --> 00:10:51.990 We are going to migrate that 245 00:10:51.990 --> 00:10:54.180 and create our schema files. 246 00:10:54.180 --> 00:10:57.390 And then we are going to have a look at this. 247 00:10:57.390 --> 00:10:58.380 The first thing we need to do 248 00:10:58.380 --> 00:10:59.670 is have a look at the routes here, 249 00:10:59.670 --> 00:11:03.180 make sure that the routes on the route 250 00:11:03.180 --> 00:11:06.540 is routed to our new scaffold correctly. 251 00:11:06.540 --> 00:11:10.440 And now we’re actually set to test if all this works. 252 00:11:10.440 --> 00:11:11.610 Let’s do that. 253 00:11:11.610 --> 00:11:16.610 Let’s do a bin dev to start up our development server. 254 00:11:16.680 --> 00:11:21.680 Let’s hop over here in our browser and look at Local 3000. 255 00:11:21.840 --> 00:11:24.000 As you can see here, this is the standard setup 256 00:11:24.000 --> 00:11:27.480 for a scaffold interface in Rails. 257 00:11:27.480 --> 00:11:29.340 Everything is working just fine. 258 00:11:29.340 --> 00:11:30.750 So let’s hop back out 259 00:11:30.750 --> 00:11:34.620 and go back to looking at the application itself 260 00:11:34.620 --> 00:11:37.530 because the main file we need to change here is, 261 00:11:37.530 --> 00:11:39.600 as we did in the Go example, 262 00:11:39.600 --> 00:11:42.720 we need to look up our deploy file. 263 00:11:42.720 --> 00:11:44.790 And it’s already filled out here in Rails. 264 00:11:44.790 --> 00:11:47.040 It’s coming a little better pre-baked 265 00:11:47.040 --> 00:11:49.770 than it is straight out of Kamal because of course we know 266 00:11:49.770 --> 00:11:51.990 that you are running a Rails application. 267 00:11:51.990 --> 00:11:54.480 But we still need to change some of the same things. 268 00:11:54.480 --> 00:11:56.460 Like we need to change your username. 269 00:11:56.460 --> 00:12:00.120 I’m gonna go back here to do my username for the image 270 00:12:00.120 --> 00:12:03.060 and the same thing for the registry. 271 00:12:03.060 --> 00:12:04.950 We have the same Kamal registry password 272 00:12:04.950 --> 00:12:05.910 we’re pulling out of ENV, 273 00:12:05.910 --> 00:12:07.830 so nothing has really changed there. 274 00:12:07.830 --> 00:12:11.730 We are going to run this with the same proxy to, 275 00:12:11.730 --> 00:12:16.230 except we are going to give it a different host name. 276 00:12:16.230 --> 00:12:19.765 This is gonna be exitsoftware.io. 277 00:12:19.765 --> 00:12:22.890 We are gonna deploy it to the same demo server that we had, 278 00:12:22.890 --> 00:12:27.090 which lives on demo.exitsoftware.io. 279 00:12:27.090 --> 00:12:28.890 And then let’s scroll down here and see what else we got. 280 00:12:28.890 --> 00:12:32.580 We got the fact that the Rails master key is being injected 281 00:12:32.580 --> 00:12:34.350 as a secret by default. 282 00:12:34.350 --> 00:12:38.520 We are running the job server here in Puma. 283 00:12:38.520 --> 00:12:40.830 That’s just how Rails 8 is already set up. 284 00:12:40.830 --> 00:12:42.450 We can actually toggle this off 285 00:12:42.450 --> 00:12:44.757 so we get a little more information when we look at things. 286 00:12:44.757 --> 00:12:49.080 And here are a couple of other new features from Kamal 2. 287 00:12:49.080 --> 00:12:50.820 These are things called aliases 288 00:12:50.820 --> 00:12:53.160 where you can then just do Kamal console, 289 00:12:53.160 --> 00:12:55.380 and you get a Rails console 290 00:12:55.380 --> 00:12:58.170 instead of having to write out all these options, 291 00:12:58.170 --> 00:12:59.940 the fact that it needs to be an interactive, 292 00:12:59.940 --> 00:13:02.793 and reused container, and all that stuff. 293 00:13:04.260 --> 00:13:06.870 We are again just building for amd64. 294 00:13:06.870 --> 00:13:08.700 We don’t need to pass anything in. 295 00:13:08.700 --> 00:13:10.110 What we are going to do though 296 00:13:10.110 --> 00:13:12.930 is we’re gonna set up accessories. 297 00:13:12.930 --> 00:13:17.220 And accessories are a way for 298 00:13:17.220 --> 00:13:20.220 Kamal to allow you to run things like a database server. 299 00:13:20.220 --> 00:13:23.190 We’re gonna host this on the same box, 300 00:13:23.190 --> 00:13:24.600 at least for the moment here. 301 00:13:24.600 --> 00:13:27.840 We’re gonna host it on exitsoftware.io. 302 00:13:27.840 --> 00:13:30.330 And then for the port, there’s something interesting. 303 00:13:30.330 --> 00:13:32.880 If we just leave it like this 3306, 304 00:13:32.880 --> 00:13:35.730 it’s gonna open that port to the whole world. 305 00:13:35.730 --> 00:13:38.850 That’s actually not what we want with this application 306 00:13:38.850 --> 00:13:41.340 where the database is running alongside 307 00:13:41.340 --> 00:13:43.500 the app service itself. 308 00:13:43.500 --> 00:13:46.440 We want it only to be accessible on local hosts. 309 00:13:46.440 --> 00:13:49.170 So Docker can do that too. 310 00:13:49.170 --> 00:13:53.580 You simply map it to 127.0.0.1, 311 00:13:53.580 --> 00:13:55.290 and then do the port. 312 00:13:55.290 --> 00:13:58.740 Then you’re gonna get that port opening just on local host 313 00:13:58.740 --> 00:14:00.780 instead of the entire world. 314 00:14:00.780 --> 00:14:02.523 That’s quite helpful. 315 00:14:03.420 --> 00:14:04.860 It’s also set up here that you could do your 316 00:14:04.860 --> 00:14:06.030 custom configuration. 317 00:14:06.030 --> 00:14:07.110 We’re not gonna use that. 318 00:14:07.110 --> 00:14:10.500 We are just gonna use the default configuration for MySQL, 319 00:14:10.500 --> 00:14:14.790 and then we have to set up the production SQL file 320 00:14:14.790 --> 00:14:17.310 that will load the initial entry point 321 00:14:17.310 --> 00:14:19.500 when the MySQL server’s first set up. 322 00:14:19.500 --> 00:14:21.540 We’ll set up in one second. 323 00:14:21.540 --> 00:14:23.010 We could also have set up Redis here, 324 00:14:23.010 --> 00:14:26.610 but we’re not gonna use that in this example. 325 00:14:26.610 --> 00:14:28.740 If we do go back up here though, 326 00:14:28.740 --> 00:14:31.740 we do need to change the database host. 327 00:14:31.740 --> 00:14:33.180 So we can change that. 328 00:14:33.180 --> 00:14:36.180 And now we’re gonna rely on 329 00:14:36.180 --> 00:14:38.850 yet another new aspect of Kamal 2, 330 00:14:38.850 --> 00:14:41.790 which is the fact that Kamal will create 331 00:14:41.790 --> 00:14:43.830 its own internal network. 332 00:14:43.830 --> 00:14:47.820 So instead of referring to this with an external IP address, 333 00:14:47.820 --> 00:14:50.910 we can refer to it with its logical name, 334 00:14:50.910 --> 00:14:53.970 which is gonna be alpha-db. 335 00:14:53.970 --> 00:14:54.900 Where does it get that from? 336 00:14:54.900 --> 00:14:58.410 It gets the db from the name of the accessory, 337 00:14:58.410 --> 00:15:01.350 and it gets the alpha from the name of the service. 338 00:15:01.350 --> 00:15:04.380 So this is how you can essentially set things up 339 00:15:04.380 --> 00:15:07.500 to be quarantine per application 340 00:15:07.500 --> 00:15:09.270 but still having multiple of them 341 00:15:09.270 --> 00:15:11.643 running on the same server. 342 00:15:12.630 --> 00:15:14.820 We’re gonna hop in here and have a look at the 343 00:15:14.820 --> 00:15:16.200 database YAML file as well. 344 00:15:16.200 --> 00:15:17.430 Let’s close this. 345 00:15:17.430 --> 00:15:21.990 And you can see here we are set up to use a root password. 346 00:15:21.990 --> 00:15:24.900 That’s actually correct for what we’re gonna use right now. 347 00:15:24.900 --> 00:15:27.150 And then normally in a real production app, 348 00:15:27.150 --> 00:15:30.600 you’d set up a custom user for this database. 349 00:15:30.600 --> 00:15:31.620 We’re not gonna do that right now. 350 00:15:31.620 --> 00:15:34.500 We’re just gonna rely on the root user, 351 00:15:34.500 --> 00:15:36.180 and then we’re gonna rely on the fact 352 00:15:36.180 --> 00:15:38.310 that we need a password here. 353 00:15:38.310 --> 00:15:41.670 And that password is something we’re gonna shove into 354 00:15:41.670 --> 00:15:42.960 the secrets file. 355 00:15:42.960 --> 00:15:45.750 You see we already have the Kamal registry password here. 356 00:15:45.750 --> 00:15:49.410 We’re gonna do the database password as well. 357 00:15:49.410 --> 00:15:52.920 And in a real app, again, you’re going to wanna use 358 00:15:52.920 --> 00:15:55.590 one of the proper ways of doing this, 359 00:15:55.590 --> 00:15:58.170 either storing this in something like one password, 360 00:15:58.170 --> 00:16:01.500 or storing it in ENV, or pulling it from a file. 361 00:16:01.500 --> 00:16:04.230 You’re definitely not gonna encode it right here, 362 00:16:04.230 --> 00:16:07.380 but I’m gonna do that anyway just for demo purposes. 363 00:16:07.380 --> 00:16:11.463 So it’s gonna be MySQL root password. 364 00:16:12.300 --> 00:16:17.300 This is absolutely not something you should do for real. 365 00:16:19.200 --> 00:16:20.100 That’s gonna be our password. 366 00:16:20.100 --> 00:16:21.810 Isn’t that great? 367 00:16:21.810 --> 00:16:26.080 Now that password is going to be injected into 368 00:16:27.030 --> 00:16:29.910 the setup here so that we can refer to it 369 00:16:29.910 --> 00:16:34.740 down for the setup in the database accessory. 370 00:16:34.740 --> 00:16:36.360 It’s gonna pull this password, 371 00:16:36.360 --> 00:16:38.640 and it’s going to essentially see the database 372 00:16:38.640 --> 00:16:40.290 that that is going to be the root password, 373 00:16:40.290 --> 00:16:43.620 and which is going to refer to that root password 374 00:16:43.620 --> 00:16:45.450 in all the cases. 375 00:16:45.450 --> 00:16:47.490 So we’re gonna have to parse 376 00:16:47.490 --> 00:16:50.490 or pass that into our Rails application as well, 377 00:16:50.490 --> 00:16:52.923 such that that has access to the MySQL root. 378 00:16:54.300 --> 00:16:57.123 Not root host, root password. 379 00:16:57.990 --> 00:17:01.740 And we are going to use that in the database YAML file here. 380 00:17:01.740 --> 00:17:04.650 Instead of this alpha database password, 381 00:17:04.650 --> 00:17:08.130 we’re gonna do the MySQL root password. 382 00:17:08.130 --> 00:17:10.180 Now we have everything set up 383 00:17:11.040 --> 00:17:12.510 to be able to refer to each other. 384 00:17:12.510 --> 00:17:16.800 And then as I said, we actually do need to just set up an 385 00:17:16.800 --> 00:17:21.420 initializer file for our database. 386 00:17:21.420 --> 00:17:23.647 We’re gonna call that Production.SQL. 387 00:17:25.170 --> 00:17:28.350 And in that you need to do create database, 388 00:17:28.350 --> 00:17:30.390 and then the different databases that you need. 389 00:17:30.390 --> 00:17:33.360 We have one database that’s called Alpha Production. 390 00:17:33.360 --> 00:17:34.980 That’s great, we need that. 391 00:17:34.980 --> 00:17:39.980 And then we also need one that is Alpha Production Cache, 392 00:17:41.190 --> 00:17:45.330 and we need one that is Alpha Production Queue, 393 00:17:45.330 --> 00:17:49.680 and we need one that is Alpha production cable. 394 00:17:49.680 --> 00:17:51.120 Where are all these coming from? 395 00:17:51.120 --> 00:17:52.200 This is Rail stuff. 396 00:17:52.200 --> 00:17:53.190 It is coming out here. 397 00:17:53.190 --> 00:17:56.310 You can see we have a cable schema, cache schema, 398 00:17:56.310 --> 00:17:57.480 what else have you? 399 00:17:57.480 --> 00:18:01.320 And they’re all defined in our database YAML file. 400 00:18:01.320 --> 00:18:02.670 Production has a primary database. 401 00:18:02.670 --> 00:18:03.750 That’s the one we just set up, 402 00:18:03.750 --> 00:18:06.330 along with a cache, queue, and cable. 403 00:18:06.330 --> 00:18:09.030 Alright, so we have now four databases we’re gonna set up. 404 00:18:09.030 --> 00:18:12.420 They’re gonna be set up with this MySQL root password, 405 00:18:12.420 --> 00:18:14.010 and we’re going to create them all 406 00:18:14.010 --> 00:18:16.020 when this is all initially set up, 407 00:18:16.020 --> 00:18:19.950 and we are going to deploy it to the existing server 408 00:18:19.950 --> 00:18:22.800 on demoexitsoftware.io. 409 00:18:22.800 --> 00:18:25.380 We’re gonna run with SSL in front of it, 410 00:18:25.380 --> 00:18:28.800 and we are going to deploy this. 411 00:18:28.800 --> 00:18:30.210 I think this is everything we need. 412 00:18:30.210 --> 00:18:33.510 Well, the first thing we do need is actually, 413 00:18:33.510 --> 00:18:35.280 let’s start a new terminal here. 414 00:18:35.280 --> 00:18:39.270 We are going to need to check all this stuff into Git. 415 00:18:39.270 --> 00:18:41.370 When you generate a new Rails application, 416 00:18:41.370 --> 00:18:44.490 it’s already been Git initialized, 417 00:18:44.490 --> 00:18:46.595 but we need to add everything to it 418 00:18:46.595 --> 00:18:49.620 and then we need to commit everything as first. 419 00:18:49.620 --> 00:18:54.420 Alright, that should make us ready to do Kamal setup. 420 00:18:54.420 --> 00:18:59.420 And Kamal setup is going to set up not only the 421 00:18:59.520 --> 00:19:00.360 application itself, 422 00:19:00.360 --> 00:19:03.630 it’s also going to set up that accessory, 423 00:19:03.630 --> 00:19:05.340 that database accessory. 424 00:19:05.340 --> 00:19:08.400 You can see here it’s setting up the Alpha DB data. 425 00:19:08.400 --> 00:19:11.550 You get to see everything that basically goes on with Kamal 426 00:19:11.550 --> 00:19:15.690 because we output all the operations that Kamal perform 427 00:19:15.690 --> 00:19:17.730 when you run things like Kamal setup 428 00:19:17.730 --> 00:19:20.130 or you run Kamal Deploy. 429 00:19:20.130 --> 00:19:23.340 You see here now we’re running and setting up the database. 430 00:19:23.340 --> 00:19:26.640 We are then going to build our Rails application 431 00:19:26.640 --> 00:19:27.750 from scratch. 432 00:19:27.750 --> 00:19:31.080 We’re gonna build that Docker container image, 433 00:19:31.080 --> 00:19:34.140 and we’re gonna push it up to Docker Hub 434 00:19:34.140 --> 00:19:36.240 just like we were doing with the Go example. 435 00:19:36.240 --> 00:19:38.700 And then we’re gonna pull it down on the server. 436 00:19:38.700 --> 00:19:42.270 And then these two applications will live side by side 437 00:19:42.270 --> 00:19:43.620 on the same server. 438 00:19:43.620 --> 00:19:47.850 They’re being routed by that proxy host configuration. 439 00:19:47.850 --> 00:19:51.360 So we can have them both live on the server 440 00:19:51.360 --> 00:19:52.200 at the same time. 441 00:19:52.200 --> 00:19:55.803 It’s one proxy, multiple applications. 442 00:19:56.850 --> 00:19:58.920 And that’s really neat. 443 00:19:58.920 --> 00:20:00.660 Now, once this is all set up, 444 00:20:00.660 --> 00:20:02.580 we will take it one step further, 445 00:20:02.580 --> 00:20:06.840 and we will move beyond my little dedicated demo server, 446 00:20:06.840 --> 00:20:10.560 and we’re gonna set up some cloud VMs on Hetzner 447 00:20:10.560 --> 00:20:14.970 to show you how you can deploy the same application 448 00:20:14.970 --> 00:20:18.180 to an entirely new setup 449 00:20:18.180 --> 00:20:20.370 using almost all the same configuration, 450 00:20:20.370 --> 00:20:22.260 only changing the things that actually do change. 451 00:20:22.260 --> 00:20:25.980 So here we have the deployments finished in 84 seconds. 452 00:20:25.980 --> 00:20:28.830 That’s not bad for building everything from scratch. 453 00:20:28.830 --> 00:20:33.330 Let’s now hop over and see if this was actually real. 454 00:20:33.330 --> 00:20:38.100 We’re gonna go to alpha, alphaexitsoftware.io. 455 00:20:38.100 --> 00:20:39.870 Here we have our real application. 456 00:20:39.870 --> 00:20:41.760 We can do Hello World. 457 00:20:41.760 --> 00:20:43.080 Hello. 458 00:20:43.080 --> 00:20:45.840 And you can see it is all successful. 459 00:20:45.840 --> 00:20:47.280 It is saving to the database. 460 00:20:47.280 --> 00:20:48.900 Everything is up and running. 461 00:20:48.900 --> 00:20:49.980 Wonderful. 462 00:20:49.980 --> 00:20:54.980 And we can check that we still have our old application, 463 00:20:55.530 --> 00:20:58.110 our Go application running on the same server on Kamago. 464 00:20:58.110 --> 00:21:00.240 Hello World times two. 465 00:21:00.240 --> 00:21:01.410 Wonderful. 466 00:21:01.410 --> 00:21:05.250 Now let’s set up some cloud VMs. 467 00:21:05.250 --> 00:21:07.320 I’m gonna use Hetzner here for that. 468 00:21:07.320 --> 00:21:11.490 We’re gonna set up three different servers. 469 00:21:11.490 --> 00:21:12.960 They’re all gonna run Ubuntu. 470 00:21:12.960 --> 00:21:16.350 I’m just gonna use some shared vCPUs here. 471 00:21:16.350 --> 00:21:18.150 Look at these amazing prices. 472 00:21:18.150 --> 00:21:21.990 I’m gonna use the smallest box I can get for this setup. 473 00:21:21.990 --> 00:21:23.970 I’m going to have my SSH key 474 00:21:23.970 --> 00:21:25.860 already configured for those boxes, 475 00:21:25.860 --> 00:21:28.350 and that’s about it. 476 00:21:28.350 --> 00:21:31.650 Let’s name them something like Alpha-Web-1, 477 00:21:31.650 --> 00:21:33.450 and then make three of them. 478 00:21:33.450 --> 00:21:37.320 We’re gonna call the last one now Alpha-db-1. 479 00:21:37.320 --> 00:21:40.410 Alright, creating these, setting these up. 480 00:21:40.410 --> 00:21:43.500 And as these are being set up, we also need a load balancer 481 00:21:43.500 --> 00:21:46.440 because now we have two application servers. 482 00:21:46.440 --> 00:21:48.600 We have web one, and we have web two, 483 00:21:48.600 --> 00:21:52.590 and we need to expose them as a single IP address 484 00:21:52.590 --> 00:21:54.540 that we can route things to. 485 00:21:54.540 --> 00:21:56.610 And we can do that as a load balancer. 486 00:21:56.610 --> 00:21:58.950 I’ll go in here and create that load balancer 487 00:21:58.950 --> 00:22:02.220 if I can get these out of the way. 488 00:22:02.220 --> 00:22:04.710 All right, we’re gonna put it in the same region. 489 00:22:04.710 --> 00:22:07.230 You can see we already have three servers available 490 00:22:07.230 --> 00:22:08.370 in this network zone. 491 00:22:08.370 --> 00:22:10.590 We’re just gonna use the smallest one. 492 00:22:10.590 --> 00:22:13.650 We don’t really even need anything but the target. 493 00:22:13.650 --> 00:22:17.370 We’re gonna declare the two alpha webs, 494 00:22:17.370 --> 00:22:19.260 web one and web two. 495 00:22:19.260 --> 00:22:21.990 We are going to bah-bah-bah. 496 00:22:21.990 --> 00:22:22.950 It’s gonna do all that. 497 00:22:22.950 --> 00:22:23.783 Yeah, that’s fine. 498 00:22:23.783 --> 00:22:27.540 We’re going to have /up be our health check 499 00:22:27.540 --> 00:22:31.020 for these servers just like Kamal itself would use. 500 00:22:31.020 --> 00:22:32.310 It’s just gonna be round robbing, 501 00:22:32.310 --> 00:22:34.803 and let’s call that Alpha-lb. 502 00:22:36.386 --> 00:22:37.500 Great. 503 00:22:37.500 --> 00:22:39.270 So that set up as well. 504 00:22:39.270 --> 00:22:41.250 Now, it’s gonna cook. 505 00:22:41.250 --> 00:22:43.200 It’s gonna get all configured up, 506 00:22:43.200 --> 00:22:45.540 but we have our three servers. 507 00:22:45.540 --> 00:22:47.880 So let’s set up our application 508 00:22:47.880 --> 00:22:49.410 to actually use these servers. 509 00:22:49.410 --> 00:22:54.410 If I hop back in here and go back to our setup, 510 00:22:54.450 --> 00:22:55.830 we have our deploy file. 511 00:22:55.830 --> 00:22:57.960 We are going to create an additional deploy file. 512 00:22:57.960 --> 00:23:00.450 So this is one of the really nice features of Kamal. 513 00:23:00.450 --> 00:23:03.360 You can have multiple destinations. 514 00:23:03.360 --> 00:23:05.370 So if we take this deploy YAML file, 515 00:23:05.370 --> 00:23:09.960 and we copy it over to be deploy Hetzner.yaml, 516 00:23:09.960 --> 00:23:13.860 we now have a new file that we can change 517 00:23:13.860 --> 00:23:14.693 for the things that change, 518 00:23:14.693 --> 00:23:17.220 but we don’t need all the things that did not change. 519 00:23:17.220 --> 00:23:19.830 So let’s first get rid of all of that. 520 00:23:19.830 --> 00:23:22.020 And now interestingly enough here, 521 00:23:22.020 --> 00:23:24.210 we are not gonna need the proxy 522 00:23:24.210 --> 00:23:26.820 because we are going to terminate SSL 523 00:23:26.820 --> 00:23:30.360 behind Cloudflare once we set everything up. 524 00:23:30.360 --> 00:23:32.490 So let’s turn off this proxy. 525 00:23:32.490 --> 00:23:34.050 By default it is actually off, 526 00:23:34.050 --> 00:23:36.000 but because everything depends 527 00:23:36.000 --> 00:23:38.400 or inherits from deploy YAML where we turn it off, 528 00:23:38.400 --> 00:23:40.890 we need to explicitly turn it off. 529 00:23:40.890 --> 00:23:43.410 Let’s also change these so these are not false. 530 00:23:43.410 --> 00:23:46.500 All this registry stuff is exactly the same. 531 00:23:46.500 --> 00:23:49.200 We are gonna change the end of those. 532 00:23:49.200 --> 00:23:52.440 So let’s leave that be exactly the DB host here. 533 00:23:52.440 --> 00:23:54.030 That’s gonna change. 534 00:23:54.030 --> 00:23:58.020 And the aliases, we don’t need to change those. 535 00:23:58.020 --> 00:24:00.060 We’re not gonna change the volume. 536 00:24:00.060 --> 00:24:03.030 We’re not gonna change the asset path or the builder, 537 00:24:03.030 --> 00:24:03.960 any of this stuff. 538 00:24:03.960 --> 00:24:06.090 We can really just boil it down. 539 00:24:06.090 --> 00:24:09.330 We are going to change though the accessory. 540 00:24:09.330 --> 00:24:12.720 Now, the first thing we’re gonna have to do is 541 00:24:12.720 --> 00:24:15.360 set up which web servers we’re deploying to. 542 00:24:15.360 --> 00:24:20.160 And let’s go over here and copy web one, 543 00:24:20.160 --> 00:24:21.840 the IP address for that. 544 00:24:21.840 --> 00:24:23.340 Hop back in. 545 00:24:23.340 --> 00:24:24.900 Great. 546 00:24:24.900 --> 00:24:27.330 We’re gonna copy over the other one as well. 547 00:24:27.330 --> 00:24:28.503 That’s web two. 548 00:24:29.908 --> 00:24:30.741 Great. 549 00:24:30.741 --> 00:24:34.773 Now we have those, we can copy over the database. 550 00:24:36.480 --> 00:24:37.470 Let’s see, where do we have that? 551 00:24:37.470 --> 00:24:39.900 First of all, we need to set it up here for the host. 552 00:24:39.900 --> 00:24:41.280 We need to set that up for the host, 553 00:24:41.280 --> 00:24:45.993 and we need to have it one more time for the host here. 554 00:24:47.550 --> 00:24:49.260 Delete to the end of line there. 555 00:24:49.260 --> 00:24:52.170 And then on this one we are actually going to set it up 556 00:24:52.170 --> 00:24:53.790 as a public port. 557 00:24:53.790 --> 00:24:56.040 Now when you do that, obviously you need a firewall 558 00:24:56.040 --> 00:24:58.560 of something else in front that ensures 559 00:24:58.560 --> 00:25:00.180 that only those two web servers 560 00:25:00.180 --> 00:25:04.500 are actually able to have access to the database set up. 561 00:25:04.500 --> 00:25:07.620 But otherwise all of this stuff is the same. 562 00:25:07.620 --> 00:25:10.260 The database host now is the only thing that we changed. 563 00:25:10.260 --> 00:25:12.420 We still need everything else. 564 00:25:12.420 --> 00:25:14.703 We need the secrets, and that’s basically it. 565 00:25:15.810 --> 00:25:18.870 Actually, we do need to set up one more thing. 566 00:25:18.870 --> 00:25:22.440 We need to have the secrets set up. 567 00:25:22.440 --> 00:25:23.880 So the secrets might have changed. 568 00:25:23.880 --> 00:25:25.980 We can actually change this to common I believe. 569 00:25:25.980 --> 00:25:28.140 But we can also just have an example here showing you 570 00:25:28.140 --> 00:25:30.423 how you can have secrets per, 571 00:25:33.540 --> 00:25:34.590 per deployment. 572 00:25:34.590 --> 00:25:37.108 And if we set that up, we’re actually gonna use 573 00:25:37.108 --> 00:25:37.941 the same to MySQL. 574 00:25:37.941 --> 00:25:38.940 Everything is gonna be the same. 575 00:25:38.940 --> 00:25:41.880 So you could do .com, and you could share that file, 576 00:25:41.880 --> 00:25:45.990 but if you have them dedicated to each destination, 577 00:25:45.990 --> 00:25:48.150 this is how you would set that up. 578 00:25:48.150 --> 00:25:51.900 Alright, I think we now have everything that we need 579 00:25:51.900 --> 00:25:54.450 to deploy our new setup 580 00:25:54.450 --> 00:25:59.070 to our new servers that are running on Hetzner. 581 00:25:59.070 --> 00:26:01.770 Oh, the host is actually gonna change, 582 00:26:01.770 --> 00:26:06.720 not in the original deploy file, but in our new setup. 583 00:26:06.720 --> 00:26:08.850 Actually, no, we don’t need to set up the host. 584 00:26:08.850 --> 00:26:10.350 The host is actually only something you need 585 00:26:10.350 --> 00:26:11.880 when you are using the proxy, 586 00:26:11.880 --> 00:26:14.940 and you are using it to run multiple applications 587 00:26:14.940 --> 00:26:16.080 on a single server 588 00:26:16.080 --> 00:26:19.410 or you’re using it to procure that SSL certificate. 589 00:26:19.410 --> 00:26:22.260 Otherwise we can just point to it from afar. 590 00:26:22.260 --> 00:26:26.010 So let’s check in our two new changes here, 591 00:26:26.010 --> 00:26:29.040 and then everything is going to get deployed, 592 00:26:29.040 --> 00:26:34.040 set up Hetzner as the, as second destination. 593 00:26:38.130 --> 00:26:39.240 Great. 594 00:26:39.240 --> 00:26:42.390 Alright, now we’re ready to deploy our application 595 00:26:42.390 --> 00:26:44.130 to this new Hetzner setup. 596 00:26:44.130 --> 00:26:48.240 So we’re gonna do Kamal setup -D for destination, 597 00:26:48.240 --> 00:26:52.080 HTC to match the name we gave that destination. 598 00:26:52.080 --> 00:26:54.750 And then we are essentially gonna run 599 00:26:54.750 --> 00:26:55.950 everything through from scratch. 600 00:26:55.950 --> 00:27:00.030 These are brand new Ubuntu procured setups 601 00:27:00.030 --> 00:27:01.230 that have nothing on them. 602 00:27:01.230 --> 00:27:03.480 So the first thing that Kamal does 603 00:27:03.480 --> 00:27:06.030 is to check whether they have Docker, which they do not. 604 00:27:06.030 --> 00:27:08.820 So they have to get Docker installed, 605 00:27:08.820 --> 00:27:10.440 and we will do that automatically. 606 00:27:10.440 --> 00:27:14.040 That happens as part of the Kamal setup process 607 00:27:14.040 --> 00:27:17.040 where everything is checked that we the need, 608 00:27:17.040 --> 00:27:18.930 the prerequisites that we have. 609 00:27:18.930 --> 00:27:19.763 And as you can see, 610 00:27:19.763 --> 00:27:22.710 that takes about 20 seconds on the first deploy. 611 00:27:22.710 --> 00:27:25.950 Then we log into Docker to be able to pull 612 00:27:25.950 --> 00:27:28.230 our Docker Hub image in just a second. 613 00:27:28.230 --> 00:27:29.340 And as you can see here, 614 00:27:29.340 --> 00:27:33.540 we still create that Kamal network on all of the setups, 615 00:27:33.540 --> 00:27:35.520 even if we don’t actually need to 616 00:27:35.520 --> 00:27:38.010 refer to an internal accessory in this case. 617 00:27:38.010 --> 00:27:41.130 Then we’re gonna build the container image. 618 00:27:41.130 --> 00:27:42.060 Again one more time, 619 00:27:42.060 --> 00:27:43.650 you can see there’s actually some of these layers 620 00:27:43.650 --> 00:27:45.690 that have already been cached. 621 00:27:45.690 --> 00:27:48.330 This is one of those really wonderful things about Docker 622 00:27:48.330 --> 00:27:49.680 that it has layer caching. 623 00:27:49.680 --> 00:27:50.970 It really speeds things up. 624 00:27:50.970 --> 00:27:52.830 And you see we’re able to just build the whole thing 625 00:27:52.830 --> 00:27:56.340 in 14 seconds with those layers cached. 626 00:27:56.340 --> 00:27:58.983 Now, the image is being pulled on all our three servers. 627 00:27:58.983 --> 00:28:01.620 It’s gonna be pulled on web one, two, 628 00:28:01.620 --> 00:28:04.440 and the DB one server that we set up. 629 00:28:04.440 --> 00:28:08.850 Everything is going to be booted on those servers 630 00:28:08.850 --> 00:28:10.530 with that image. 631 00:28:10.530 --> 00:28:12.180 I suppose on the accessory server. 632 00:28:12.180 --> 00:28:15.450 On the DB server, we’re gonna boot MySQL 633 00:28:15.450 --> 00:28:18.300 on its own server, instead of what we were doing before 634 00:28:18.300 --> 00:28:21.360 where we’re rebooting it on the same server 635 00:28:21.360 --> 00:28:22.530 as we were deploying everything else. 636 00:28:22.530 --> 00:28:26.970 So, alright, so now in 88 seconds we have set up 637 00:28:26.970 --> 00:28:31.020 a dedicated server from MySQL, two of these web app servers. 638 00:28:31.020 --> 00:28:34.020 And now we can go back here 639 00:28:34.020 --> 00:28:37.530 and check if our load balancer is ready. 640 00:28:37.530 --> 00:28:40.500 It’s gonna have this IP address. 641 00:28:40.500 --> 00:28:42.420 It probably won’t be ready for a few seconds 642 00:28:42.420 --> 00:28:46.350 because it pings every 10-15 seconds, something like that. 643 00:28:46.350 --> 00:28:50.220 But while it’s getting ready, let’s go into Cloudflare, 644 00:28:50.220 --> 00:28:52.140 which is where I’m managing my domain. 645 00:28:52.140 --> 00:28:54.510 And we’re gonna set up a new record. 646 00:28:54.510 --> 00:28:56.460 It’s gonna be an A record for Bravo, 647 00:28:56.460 --> 00:28:59.280 which is what we’re gonna call the destination 648 00:28:59.280 --> 00:29:00.960 for this deployment. 649 00:29:00.960 --> 00:29:04.350 And we’re gonna use the IP address of the load balancer, 650 00:29:04.350 --> 00:29:06.330 and we’re gonna set it up as being proxy. 651 00:29:06.330 --> 00:29:10.833 That means Cloudflare is going to terminate the SSL. 652 00:29:10.833 --> 00:29:14.263 It’s also gonna be doing CDN work. 653 00:29:14.263 --> 00:29:16.606 It’s a really nice setup to have it like this. 654 00:29:16.606 --> 00:29:18.780 All right, so now we have Bravo being proxy 655 00:29:18.780 --> 00:29:20.490 to the load balancer. 656 00:29:20.490 --> 00:29:23.400 And look and behold, our load balancer is healthy, 657 00:29:23.400 --> 00:29:25.140 and it’s ready to go. 658 00:29:25.140 --> 00:29:28.620 So let’s see if it all works. 659 00:29:28.620 --> 00:29:31.740 Bravo exitsoftware.io. 660 00:29:31.740 --> 00:29:32.573 Wonderful. 661 00:29:32.573 --> 00:29:37.460 Now we have a two web app server setup 662 00:29:40.260 --> 00:29:45.150 that is with a dedicated database, 663 00:29:45.150 --> 00:29:48.120 and it is running by itself. 664 00:29:48.120 --> 00:29:51.000 And by the way, we still of course have our own setup 665 00:29:51.000 --> 00:29:53.133 of the same application running on Alpha, 666 00:29:54.180 --> 00:29:56.400 and we can deploy back and forth between these two things. 667 00:29:56.400 --> 00:29:59.400 So now we have two deployments of this same application, 668 00:29:59.400 --> 00:30:02.430 and we can do a few Kamal things. 669 00:30:02.430 --> 00:30:07.430 Like we can look at the logs for the Hetzner setup. 670 00:30:08.580 --> 00:30:11.040 That’s going to show us that index controller 671 00:30:11.040 --> 00:30:13.830 we just accessed there. 672 00:30:13.830 --> 00:30:14.663 What else can we do? 673 00:30:14.663 --> 00:30:17.550 We can do things like we can access the console, 674 00:30:17.550 --> 00:30:21.060 which is going to grab the first of our web servers 675 00:30:21.060 --> 00:30:24.600 and give us a console for Rails. 676 00:30:24.600 --> 00:30:25.560 And what do we have here? 677 00:30:25.560 --> 00:30:27.090 Let’s see if we can load that first post. 678 00:30:27.090 --> 00:30:29.280 You can see, there we have it. 679 00:30:29.280 --> 00:30:33.060 We can even update that post and set a new title. 680 00:30:33.060 --> 00:30:35.463 Let’s do change from console. 681 00:30:36.360 --> 00:30:39.420 Let’s hop back and see that that actually took effect. 682 00:30:39.420 --> 00:30:42.483 It did, changed from console right here. 683 00:30:44.220 --> 00:30:47.130 This is Kamal. 684 00:30:47.130 --> 00:30:51.120 You are able to run it first on a single box, 685 00:30:51.120 --> 00:30:53.430 either with just something like SQL Light 686 00:30:53.430 --> 00:30:57.810 or using an accessory with the existing Kamal network 687 00:30:57.810 --> 00:31:00.330 to all have it operate inside of itself, 688 00:31:00.330 --> 00:31:02.700 or you can set it up with multiple servers 689 00:31:02.700 --> 00:31:05.580 like we just did in this example. 690 00:31:05.580 --> 00:31:08.340 And of course, it’s very easy to expand that. 691 00:31:08.340 --> 00:31:10.200 You can add as many servers as you want. 692 00:31:10.200 --> 00:31:13.565 You can start classifying different types of servers. 693 00:31:13.565 --> 00:31:17.760 You could have job servers running something like SQL Jobs 694 00:31:17.760 --> 00:31:20.550 as we do in Rails now with Solid Queue. 695 00:31:20.550 --> 00:31:22.560 You have a ton of options. 696 00:31:22.560 --> 00:31:25.020 We can configure how many processes 697 00:31:25.020 --> 00:31:27.180 we wanna run on each server. 698 00:31:27.180 --> 00:31:31.530 You have all the power of Kamal right at your fingers 699 00:31:31.530 --> 00:31:33.150 for any type of application, 700 00:31:33.150 --> 00:31:35.670 all the way from a Go Hello World 701 00:31:35.670 --> 00:31:39.330 to a full three tier Rails application 702 00:31:39.330 --> 00:31:41.490 with three different servers. 703 00:31:41.490 --> 00:31:42.690 It’s pretty amazing. 704 00:31:42.690 --> 00:31:44.850 It’ll work great on cloud VMs. 705 00:31:44.850 --> 00:31:47.760 It’ll work great on a dedicated box. 706 00:31:47.760 --> 00:31:50.340 It’ll work great on your own hardware. 707 00:31:50.340 --> 00:31:52.980 You just go in and add a second destination, 708 00:31:52.980 --> 00:31:55.440 or you change your Deploy YAML file 709 00:31:55.440 --> 00:31:57.780 to be the new destination. 710 00:31:57.780 --> 00:32:00.030 If we were to move this to DigitalOcean, 711 00:32:00.030 --> 00:32:01.920 I would just change these IP addresses, 712 00:32:01.920 --> 00:32:05.637 and I would run Kamal, setup -D DigitalOcean, 713 00:32:05.637 --> 00:32:09.150 and I would be up and running on the new server immediately. 714 00:32:09.150 --> 00:32:10.530 This is the power of Kamal. 715 00:32:10.530 --> 00:32:11.700 It’s pretty incredible. 716 00:32:11.700 --> 00:32:13.473 I hope you enjoy it.