1 00:00:00,090 --> 00:00:01,840 ‫Let's talk about the last routing policy, 2 00:00:01,840 --> 00:00:02,900 ‫which is Multi-Value, 3 00:00:02,900 --> 00:00:04,770 ‫which is going to be used when you want to route traffic 4 00:00:04,770 --> 00:00:06,300 ‫to multiple resources. 5 00:00:06,300 --> 00:00:07,930 ‫And Route 53 will therefore 6 00:00:07,930 --> 00:00:10,390 ‫return multiple values or resources. 7 00:00:10,390 --> 00:00:12,960 ‫Now, you can associate them with Health Checks, 8 00:00:12,960 --> 00:00:15,520 ‫and so therefore the only resources returned 9 00:00:15,520 --> 00:00:18,070 ‫via the Multi-Value policy are going to be the ones 10 00:00:18,070 --> 00:00:20,070 ‫that are associated with a healthy Health Check. 11 00:00:20,070 --> 00:00:22,700 ‫So up to eight healthy records are going to be returned 12 00:00:22,700 --> 00:00:24,143 ‫for each Multi-Value query. 13 00:00:25,226 --> 00:00:26,190 ‫And although it looks like an ELB, 14 00:00:26,190 --> 00:00:28,310 ‫it's not a substitute for having an ELB. 15 00:00:28,310 --> 00:00:31,510 ‫The idea is that it's the client-side load balancing. 16 00:00:31,510 --> 00:00:33,201 ‫So let's look at an example. 17 00:00:33,201 --> 00:00:34,940 ‫We are going to set up multiple A Records 18 00:00:34,940 --> 00:00:36,920 ‫for our example.com, 19 00:00:36,920 --> 00:00:38,460 ‫and we associate them with Health Checks. 20 00:00:38,460 --> 00:00:41,550 ‫So when a Multi-Value query is done by our clients, 21 00:00:41,550 --> 00:00:43,650 ‫it's going to receive up to eight records back, 22 00:00:43,650 --> 00:00:45,440 ‫and then the clients will choose one of them. 23 00:00:45,440 --> 00:00:48,840 ‫But at least by combining this with Health Checks, 24 00:00:48,840 --> 00:00:52,840 ‫we know that one of the eight records being returned, 25 00:00:52,840 --> 00:00:54,560 ‫or up to eight, are going to be healthy. 26 00:00:54,560 --> 00:00:55,420 ‫And therefore the client 27 00:00:55,420 --> 00:00:58,573 ‫can have very safe queries into them. 28 00:00:59,990 --> 00:01:01,410 ‫This is going to be different, for example, 29 00:01:01,410 --> 00:01:05,370 ‫when you have a simple routing with multiple values in it, 30 00:01:05,370 --> 00:01:07,900 ‫because as you know, the simple routing policy 31 00:01:07,900 --> 00:01:09,120 ‫does not allow for Health Checks, 32 00:01:09,120 --> 00:01:10,140 ‫and therefore it's possible 33 00:01:10,140 --> 00:01:12,810 ‫that one of the resources returned in the query 34 00:01:12,810 --> 00:01:15,970 ‫of a simple routing policy will be unhealthy. 35 00:01:15,970 --> 00:01:18,830 ‫This is why Multi-Value are a little bit more powerful 36 00:01:18,830 --> 00:01:20,100 ‫as types of records. 37 00:01:20,100 --> 00:01:22,870 ‫So let's have a look in the UI at how we can test them. 38 00:01:22,870 --> 00:01:26,640 ‫So let's practice the Multi-Value record. 39 00:01:26,640 --> 00:01:29,000 ‫So let's go and create a multi-record, 40 00:01:29,000 --> 00:01:31,070 ‫so a multi dot blah blah blah. 41 00:01:31,070 --> 00:01:32,120 ‫And then the value of it 42 00:01:32,120 --> 00:01:34,220 ‫is going to be linked to us-east-1. 43 00:01:34,220 --> 00:01:36,580 ‫So I will add this value here, 44 00:01:36,580 --> 00:01:39,790 ‫and then the Routing policy is going to be Multivalue. 45 00:01:39,790 --> 00:01:41,690 ‫The Health check is going to be us-east-1. 46 00:01:41,690 --> 00:01:44,300 ‫And the Record is going to be US. 47 00:01:44,300 --> 00:01:46,710 ‫And TTL is going to be 60 seconds. 48 00:01:46,710 --> 00:01:47,710 ‫Let's add another Record. 49 00:01:47,710 --> 00:01:50,050 ‫So, multi, and again, 50 00:01:50,050 --> 00:01:51,720 ‫we're going to route to a different region, 51 00:01:51,720 --> 00:01:53,570 ‫so this one is ap-southeast-1. 52 00:01:53,570 --> 00:01:56,920 ‫So the answer is Multivalue answer. 53 00:01:56,920 --> 00:01:58,780 ‫The Health check is ap-southeast-1. 54 00:01:58,780 --> 00:02:02,630 ‫And the Record ID is going to be Asia. 55 00:02:02,630 --> 00:02:05,140 ‫And then the record TTL is one minute. 56 00:02:05,140 --> 00:02:07,190 ‫And then finally, the last one, 57 00:02:07,190 --> 00:02:09,730 ‫so again, one more Record name. 58 00:02:09,730 --> 00:02:14,730 ‫The Value is going to be linked to eu-central-1 right here. 59 00:02:14,830 --> 00:02:16,610 ‫The TTL is one minute. 60 00:02:16,610 --> 00:02:19,700 ‫And the Routing policy is Multivalue answer. 61 00:02:19,700 --> 00:02:20,700 ‫And for the Health checks, 62 00:02:20,700 --> 00:02:25,050 ‫we're going to use the one from eu-central-1. 63 00:02:25,050 --> 00:02:26,910 ‫And the Record ID is EU. 64 00:02:26,910 --> 00:02:29,750 ‫Okay, so let's create these records. 65 00:02:29,750 --> 00:02:31,740 ‫And the records are successfully created. 66 00:02:31,740 --> 00:02:33,040 ‫Now let's test it out. 67 00:02:33,040 --> 00:02:35,620 ‫So for this, we're going to use our CloudShell in here. 68 00:02:35,620 --> 00:02:37,840 ‫So let's reconnect to CloudShell. 69 00:02:37,840 --> 00:02:40,650 ‫And what I want to do is to test this record. 70 00:02:40,650 --> 00:02:43,310 ‫So I will copy the record in here, 71 00:02:43,310 --> 00:02:46,240 ‫and then I will clear my screen. 72 00:02:46,240 --> 00:02:49,280 ‫And so if I test a dig on this, 73 00:02:49,280 --> 00:02:50,550 ‫then I get three answers. 74 00:02:50,550 --> 00:02:52,750 ‫So the three IPs are returned, 75 00:02:52,750 --> 00:02:53,840 ‫and the reason is, well, 76 00:02:53,840 --> 00:02:57,400 ‫the three health checks are fully working. 77 00:02:57,400 --> 00:02:59,210 ‫So as you can see, they're all healthy. 78 00:02:59,210 --> 00:03:00,740 ‫But if I take one of them, for example, 79 00:03:00,740 --> 00:03:02,400 ‫I remove the eu-central-1, 80 00:03:02,400 --> 00:03:04,130 ‫so I'm gonna make this one unhealthy, 81 00:03:04,130 --> 00:03:05,390 ‫and I'm just going to trick it 82 00:03:05,390 --> 00:03:08,700 ‫by editing and do an Invert health status. 83 00:03:08,700 --> 00:03:10,350 ‫So this is going to make the healthy unhealthy, 84 00:03:10,350 --> 00:03:11,200 ‫and vice versa. 85 00:03:11,200 --> 00:03:12,170 ‫It's just a quick way for me 86 00:03:12,170 --> 00:03:15,240 ‫to create an unhealthy health check. 87 00:03:15,240 --> 00:03:16,830 ‫So let me pause right now. 88 00:03:16,830 --> 00:03:20,740 ‫Okay, so now my eu-central-1 health check is Unhealthy. 89 00:03:20,740 --> 00:03:24,200 ‫And so if I reissue a dig command right here, 90 00:03:24,200 --> 00:03:27,510 ‫I should expect to see only two values, yes, as a result. 91 00:03:27,510 --> 00:03:29,433 ‫So the Multivalue answer has worked, 92 00:03:29,433 --> 00:03:30,490 ‫and it worked really well. 93 00:03:30,490 --> 00:03:32,890 ‫So just to revert this, edit this health check, 94 00:03:32,890 --> 00:03:36,300 ‫and let's untick this Invert health check status, 95 00:03:36,300 --> 00:03:37,730 ‫and we're good to go. 96 00:03:37,730 --> 00:03:39,210 ‫Okay, so that's it for this lecture. 97 00:03:39,210 --> 00:03:40,220 ‫I hope you liked it. 98 00:03:40,220 --> 00:03:42,170 ‫And I will see you in the next lecture.