WEBVTT 00:00.800 --> 00:01.430 Now what? 00:01.460 --> 00:04.770 Now what I'm going to do is I want. 00:06.530 --> 00:08.120 I don't think I can say is the host name. 00:10.040 --> 00:12.140 Let me call it up one. 00:15.180 --> 00:16.290 It is a good design. 00:17.100 --> 00:18.180 It is a good design. 00:18.750 --> 00:21.060 But the problem is, if your hub goes down. 00:22.320 --> 00:23.580 Your hub is not working. 00:23.730 --> 00:25.530 Will your spokes communicate to each other? 00:27.250 --> 00:29.440 They will for two hours. 00:29.440 --> 00:32.840 They will for two hours. 00:32.860 --> 00:33.850 There's not a problem. 00:34.090 --> 00:38.170 After two hours, when they go to reregister themselves to the hub, they will not. 00:38.170 --> 00:43.030 And if they want to go to a new spoke, which they have not talked to earlier, will not be able to 00:43.030 --> 00:45.820 go because the control plane traffic is not allowed. 00:47.380 --> 00:50.440 So as long as they have the mappings two hours, no problem. 00:50.650 --> 00:56.080 But the moment that overrides the moment the time is over, they will not be able to communicate to 00:56.080 --> 00:56.620 others. 00:57.910 --> 00:59.040 How will I fix that? 00:59.050 --> 01:00.370 I will have two hubs. 01:01.780 --> 01:02.860 I will have two hubs. 01:02.860 --> 01:07.080 One of them will be active during both of them will be active at the same time. 01:07.090 --> 01:09.310 The good thing about that is both of them will be active. 01:09.910 --> 01:12.430 One of them goes down, the other one is already active. 01:12.670 --> 01:19.780 It's not like if you have done failover in firewalls, if you have, then one state is active, one 01:19.780 --> 01:22.480 is standby, so the other one is not working at all. 01:22.750 --> 01:26.780 But when one guy dies, the other one comes up right. 01:26.780 --> 01:29.000 That's a different case than this here. 01:29.000 --> 01:30.710 I will not do that here. 01:30.710 --> 01:32.510 Both of them will be active at the same time. 01:32.510 --> 01:38.480 So if R4 wants to resolve his mappings, he can either go to 1 or 2, depending upon which is available, 01:38.480 --> 01:40.580 and then after that, go forward. 01:41.180 --> 01:42.260 Let's do that. 01:42.950 --> 01:43.520 For that. 01:43.520 --> 01:45.500 What I'll do is I'll go to R2 first. 01:47.360 --> 01:50.900 No interface, Tunnel zero, remove the tunnel, create it again. 01:52.340 --> 01:55.040 IP address 192168.1.2. 02:00.960 --> 02:05.130 Starting from R1 again, I removed it, so I'll have to do everything again. 02:05.730 --> 02:09.210 Tunnel Source Serial zero zero Tunnel Mode. 02:10.290 --> 02:18.630 MultiPoint IP and IP Network ID ten IP Map Multicast to dynamic. 02:19.260 --> 02:19.950 That's all 02:24.600 --> 02:25.080 good, right? 02:25.470 --> 02:26.160 That's enough. 02:26.190 --> 02:32.880 The only problem here will be you will have no mappings because the spokes don't know that the hub has 02:32.880 --> 02:33.390 gone down. 02:33.390 --> 02:35.670 They think they have already registered themselves. 02:36.810 --> 02:37.010 Right. 02:37.020 --> 02:41.430 So if the hub goes down here, what you'll have to do is you'll have to either wait for two hours because 02:41.430 --> 02:45.270 after that they'll come and register themselves again or go to the tunnel. 02:45.480 --> 02:53.340 No IP network ID ten IP and network ID, the new IP, bring it back in again. 02:53.340 --> 02:55.010 Or you could just show shut and no shut. 02:55.050 --> 02:55.950 Both will work the same. 02:58.470 --> 03:02.740 No IP and network ID ten IP and network ID. 03:12.300 --> 03:13.370 This time of the year? 03:13.470 --> 03:13.730 No. 03:16.410 --> 03:16.840 Interesting. 03:23.100 --> 03:24.460 So you see that it's not. 03:24.460 --> 03:27.610 So I'll just shut and I'll have to wait for the command then. 03:27.610 --> 03:28.540 I don't want to do that. 03:33.150 --> 03:33.630 Shut. 03:40.790 --> 03:41.270 Shut. 03:51.380 --> 03:51.620 Right. 03:51.800 --> 03:54.590 So show IP neighbors. 03:55.220 --> 03:56.090 No neighbors. 03:58.930 --> 04:00.000 So I'd be happy. 04:01.330 --> 04:06.040 The mappings are for three, four, five, two two are not done anything. 04:06.040 --> 04:09.340 What I'll do is on two no interface channel zero. 04:09.740 --> 04:10.840 I'll remove the tunnel from two. 04:10.840 --> 04:15.760 I don't want to to be part of the I don't want him to come and register himself to the top. 04:20.050 --> 04:20.950 The mappings are here. 04:20.950 --> 04:24.510 12168.1.2.1.2. 04:24.520 --> 04:25.390 I'll use connectivity. 04:25.450 --> 04:29.920 1.21.3 has one problem. 04:32.680 --> 04:33.430 IPsec is the. 04:34.690 --> 04:35.620 I'm running protection. 04:35.620 --> 04:36.070 Right. 04:37.000 --> 04:38.710 I'll have to clear the protection. 04:38.980 --> 04:45.700 No IP, no Crypto IPsec Tunnel protection. 05:11.580 --> 05:11.910 Problem. 05:11.910 --> 05:12.830 What is happening right now? 05:12.840 --> 05:15.240 The hello packet coming from one side is coming encrypted. 05:15.720 --> 05:18.450 The other side has not run encryption because he's not running. 05:19.650 --> 05:20.180 Right. 05:20.780 --> 05:21.630 The second half. 05:21.970 --> 05:22.530 Second half. 05:23.460 --> 05:24.080 Why can't you. 05:27.920 --> 05:30.290 Definitely, though, I would do that. 05:30.290 --> 05:32.180 But the problem is I made a mistake. 05:33.170 --> 05:36.050 I removed the tongue from R1, which was the hub. 05:37.190 --> 05:38.630 That's why I'm bringing it back up again. 05:40.520 --> 05:42.950 I removed the tunnel completely from R1 that caused the problem. 05:42.950 --> 05:44.270 Otherwise I didn't have to do that. 05:44.270 --> 05:46.610 I'm moving back to what I was doing before. 05:46.820 --> 05:51.650 So now it's okay, Now it's back to normal right now. 05:52.040 --> 05:53.510 So if you do, you ship it out. 05:54.530 --> 06:02.330 You should have ten dot zero network if you want to go to ten .4.4.41.5.5.5 with a source of ten .4.4.4. 06:02.480 --> 06:04.580 You can right? 06:04.580 --> 06:07.010 So you'll have the resolutions right here. 06:07.520 --> 06:08.540 Phase three is working. 06:09.170 --> 06:11.570 Now I want R2 to be the other half. 06:12.260 --> 06:18.770 So what I'll do is I'll go to Interface Tunnel zero IP address 192168.1.2. 06:21.000 --> 06:21.230 Right. 06:21.960 --> 06:22.920 Source the same. 06:24.480 --> 06:25.140 Zero zero. 06:25.770 --> 06:26.490 Final destination. 06:26.550 --> 06:26.970 Don't have. 06:26.970 --> 06:27.810 It's a tunnel. 06:27.810 --> 06:31.540 So tunnel mode and. 06:37.190 --> 06:41.390 Then I need to do the same exact thing that I used to do on the other half. 06:41.610 --> 06:42.050 Yes. 06:44.520 --> 06:45.330 On the spokes? 06:45.330 --> 06:45.810 Yes. 06:45.840 --> 06:47.160 On the spokes, if you check. 06:47.190 --> 06:51.840 Do show run in tunnel interface Channel zero. 06:53.190 --> 06:56.010 If you check your interface Tunnel zero right now, your NHS is home. 06:57.330 --> 07:03.530 You also have home IP and NHS 182 168.1.. 07:04.860 --> 07:06.720 You also have the mapping for it. 07:07.810 --> 07:12.570 182 static map for the other hub is 151 .16.2. 07:15.140 --> 07:15.560 26. 07:15.960 --> 07:16.400 R2. 07:17.000 --> 07:19.610 So I added this guy. 07:19.880 --> 07:21.410 I also mapped the other guy. 07:21.800 --> 07:23.030 What else do I need to do? 07:24.290 --> 07:25.250 Multicast. 07:25.790 --> 07:27.990 I'm sending my multicast only to R1 right now. 07:28.010 --> 07:29.960 I also need to send it to R2. 07:29.990 --> 07:34.430 So IP and map multicast. 07:34.580 --> 07:37.310 151 dot 26 dot. 07:40.900 --> 07:44.590 He has IP multicast, he doesn't know what the destination for that multicast is. 07:44.620 --> 07:45.760 The outside destination. 07:47.020 --> 07:48.220 220 400 ten. 07:48.250 --> 07:49.510 He doesn't know where to send it to. 07:49.540 --> 07:51.490 So the outside header should be one. 07:51.520 --> 07:53.110 It should send it to 16.1. 07:53.110 --> 07:55.600 It should also send it to 26.2. 07:55.600 --> 07:58.180 So if you use this again, this is your config now. 07:59.710 --> 08:03.040 192 168 1.11 92 1681.2. 08:03.490 --> 08:07.840 My mappings are for both, my multicast is being sent to both of them. 08:09.580 --> 08:09.890 Correct. 08:10.600 --> 08:12.260 I'll copy the exact same thing. 08:12.280 --> 08:18.460 That's the best thing about Dmvpn is you can copy paste because I want all of them to point to the same 08:18.460 --> 08:18.940 guy. 08:19.480 --> 08:21.070 I'll copy it from one spoke. 08:24.030 --> 08:26.110 Paste it on the others because nothing changes. 08:26.110 --> 08:27.550 They're all pointing to the same guy. 08:28.180 --> 08:29.020 Also, our five 08:31.900 --> 08:32.680 pointed to the same. 08:34.570 --> 08:34.930 Correct. 08:34.970 --> 08:37.810 They're all sending their multicast to R2. 08:37.840 --> 08:40.690 So you'll see the neighbors are coming up from R2 side. 08:40.690 --> 08:48.280 But from here also, I need to say map multicast to all the dynamically learned frames. 08:49.040 --> 08:49.380 So. 08:53.700 --> 09:01.050 So if you see right now, what is going to happen is these spokes will not go only go register themselves 09:01.050 --> 09:05.220 to R1, they will also register themselves to R2. 09:05.820 --> 09:10.200 And when he is sending the multicast, he sends it here as well as here. 09:11.220 --> 09:13.230 R1 replies, R2 replies. 09:13.230 --> 09:18.210 So R4 now will have two neighbors, not just one will be a problem. 09:19.260 --> 09:22.340 I can use the ten dot and go to R1 and R2. 09:22.560 --> 09:23.730 Yes, load balance it. 09:25.740 --> 09:30.320 And then what about it is contiguous in what kind of discontiguous? 09:31.760 --> 09:34.820 Reached in darkness to the both of them. 09:35.090 --> 09:35.600 Yeah. 09:35.840 --> 09:37.200 Both of them have the hubs. 09:37.250 --> 09:38.300 Both of them have the mapping. 09:38.300 --> 09:40.270 So if I'm going from this hub, he will redirect. 09:40.280 --> 09:42.320 If I'm going from that hub, he will redirect. 09:43.310 --> 09:44.480 Both are active, right? 09:45.170 --> 09:49.190 It doesn't matter for me which hub am I using to make a decision because. 09:51.640 --> 09:51.910 Yeah. 09:53.750 --> 09:54.160 Okay. 09:56.240 --> 09:57.320 What do you mean by that? 09:57.350 --> 09:58.730 What is in the middle? 09:59.990 --> 10:00.980 Nothing is in the middle. 10:01.010 --> 10:02.380 See our for to reach our three. 10:02.390 --> 10:03.520 He has two ways. 10:03.530 --> 10:05.840 You can either go this way or you can go this way. 10:05.970 --> 10:07.550 You mean you have the 192? 10:08.150 --> 10:08.810 168? 10:09.890 --> 10:12.900 It's like having an explosive. 10:13.520 --> 10:14.780 Yeah, but I'm not using summary. 10:14.780 --> 10:15.290 Right. 10:16.490 --> 10:18.050 He's sending it out at 10.4. 10:18.080 --> 10:20.720 He's sending it as out as 10.3. 10:20.990 --> 10:25.130 But R1 and R2, R1 and R2 are summarizing it. 10:25.130 --> 10:25.730 That's okay. 10:25.730 --> 10:30.860 So R4, if he wants to go to any ten network, he's going from there, either from here or from there? 10:32.600 --> 10:34.190 No, you can go anywhere. 10:34.430 --> 10:35.180 Load balance. 10:36.650 --> 10:38.740 You can either go from here or it can go from there. 10:38.750 --> 10:42.080 Now, depending upon which one is closer to him, it will use that one. 10:43.640 --> 10:44.240 Check this out. 10:44.660 --> 10:48.020 What I've made here are four and R3 to go to each other. 10:48.050 --> 10:48.890 They have two paths. 10:48.920 --> 10:50.700 Now, earlier they had only one path. 10:50.910 --> 10:52.290 Now I have two paths. 10:52.320 --> 10:54.780 But the good thing is that both paths have everything. 10:55.140 --> 10:57.290 This has all the network IDs. 10:57.300 --> 10:58.960 This has all the network IDs. 10:58.990 --> 10:59.340 So. 11:01.060 --> 11:03.580 You just keep the table on there. 11:04.450 --> 11:06.670 Before that, let me see if my neighbors are up. 11:08.290 --> 11:09.200 It's up from here. 11:09.220 --> 11:10.150 Are they up from here? 11:12.870 --> 11:13.610 Not them yet. 11:13.620 --> 11:14.790 I need to shut No, shut. 11:16.140 --> 11:16.290 Right. 11:16.320 --> 11:18.120 Because I just added the multicast command. 11:18.480 --> 11:23.640 Either shut and no shut or an IP network, whether it's shut because sometimes with an IP network. 11:24.210 --> 11:26.250 Your mappings will be incomplete. 11:26.520 --> 11:27.090 It doesn't go. 11:27.210 --> 11:30.210 If you don't wait for enough time, it will not be complete. 11:31.080 --> 11:32.670 So go back here. 11:33.090 --> 11:33.420 No. 11:33.420 --> 11:35.670 Shut on the spokes. 11:36.150 --> 11:39.240 No, shut, No, shut. 11:41.490 --> 11:42.360 Both neighbors are up. 11:43.020 --> 11:44.820 So IP neighbors. 11:46.230 --> 11:51.630 From here also show IP neighbors from our five also. 11:55.820 --> 11:56.780 Now the right right. 11:56.780 --> 11:58.640 You want to see the route from, let's say, R3. 11:58.670 --> 12:00.140 Now, my spokes are only three. 12:00.380 --> 12:01.610 R3, R4 and R5. 12:01.760 --> 12:04.490 Let's check from R3 show IP route. 12:08.690 --> 12:11.270 10.2 is going from 180 to 168. 12:11.300 --> 12:17.150 1.2.0 is going from 1.1 show IP. 12:17.510 --> 12:20.210 IP That's before. 12:20.870 --> 12:22.610 This is before using the command. 12:24.890 --> 12:27.380 No IP Split Horizon. 12:27.950 --> 12:28.610 IP split. 12:28.760 --> 12:29.750 No IP split horizon. 12:30.200 --> 12:32.390 One is not forwarding the other house. 12:33.380 --> 12:39.560 Now he'll forward the other house and you'll see that if you do a show IP route here now you should 12:39.560 --> 12:48.230 have all the routes, but going from 1.2, I need to do what? 12:50.090 --> 12:50.870 Auto summary. 12:52.970 --> 12:56.930 So now you'll see ten dot zero both ways. 12:56.930 --> 13:00.140 You have to do that one already before from the before. 13:00.710 --> 13:03.050 I didn't change the IP, I removed the tunnel. 13:04.580 --> 13:05.450 Yeah, both of them. 13:07.020 --> 13:07.890 It it is. 13:07.890 --> 13:08.490 It is there. 13:11.550 --> 13:12.240 It's already there. 13:12.240 --> 13:13.290 The command auto summary. 13:13.710 --> 13:14.700 I was using it from before. 13:14.700 --> 13:15.060 Right. 13:15.960 --> 13:16.530 Why doesn't it. 13:17.280 --> 13:18.300 It is summarizing. 13:20.190 --> 13:20.700 Check this out. 13:20.700 --> 13:21.540 It is summarizing it. 13:25.080 --> 13:28.860 Now for our three to go anywhere it has. 13:28.860 --> 13:29.910 How many summaries? 13:30.930 --> 13:32.310 Two ways of going there. 13:32.340 --> 13:34.860 1.21.1. 13:35.220 --> 13:38.790 So now you check your traffic can go to both of them. 13:38.940 --> 13:42.360 Ten .4.4.4 from the source of 1.3.3.3. 13:44.310 --> 13:45.510 This is just one hop. 13:49.400 --> 13:51.050 Then the next part will go. 13:53.640 --> 13:56.330 Now we can go to either this guy or that guy. 13:56.340 --> 13:57.120 He went to both. 13:57.720 --> 13:59.340 He sent his resolution to both. 13:59.340 --> 13:59.970 He got a reply. 14:00.000 --> 14:00.570 From whom? 14:02.310 --> 14:04.770 From to two replied first. 14:04.770 --> 14:05.970 So he goes from two. 14:07.440 --> 14:16.320 Now, if you check if you check your topology right here, you'll see that for R4 two, go to R3 for 14:16.320 --> 14:18.180 10.42, go to 10.3. 14:18.450 --> 14:22.080 The next stop is whom this as well as. 14:23.070 --> 14:28.020 So he will send the packet from, let's say here or the other side. 14:28.020 --> 14:29.550 If he sends from this guy. 14:30.840 --> 14:37.320 Right, the redirect will be sent and he will resolve the request, resolve, request, resolve, send 14:37.320 --> 14:40.050 direct, or he can choose the other one. 14:41.940 --> 14:46.320 You can send this traffic from here, depending upon what source you're using. 14:46.470 --> 14:49.710 If it sends from here, redirect will be sent by this guy. 14:49.740 --> 14:52.750 They'll resolve it and direct scope to spoke communication. 14:52.840 --> 14:54.040 You have a 150. 14:55.640 --> 14:56.340 Minus eight. 14:56.810 --> 15:00.200 And you do what normally work in the area. 15:00.770 --> 15:01.580 And I wouldn't. 15:02.030 --> 15:02.610 You wouldn't? 15:03.620 --> 15:10.340 It would, but it would cause the problem of what you're talking about is you have two networks, right? 15:11.510 --> 15:12.710 They're both 150. 15:17.700 --> 15:18.660 I mean, not like that. 15:19.050 --> 15:19.710 This is ten. 15:21.810 --> 15:28.410 Then when you when you summarize it, he summarizes it out as, what, ten? 15:30.150 --> 15:31.290 So you have two routes now. 15:31.290 --> 15:36.090 One is directly connected to the other one is will work on the longest match, right? 15:36.090 --> 15:40.420 So from here when you ping ten .2.2.2, it doesn't match this, it will match this. 15:40.420 --> 15:41.460 So will forward the packet. 15:43.320 --> 15:44.190 That wouldn't be a problem. 15:44.850 --> 15:50.860 And you have a you have a network in the middle, let's say maybe 170 directly connected. 15:50.910 --> 15:51.480 Sure. 15:52.350 --> 15:52.890 Yeah. 15:53.220 --> 15:53.460 Okay. 15:54.690 --> 15:55.530 Yeah, sure. 15:55.530 --> 15:57.330 And you have ten networks on either side. 15:57.570 --> 15:58.050 Okay. 15:58.200 --> 16:04.820 So when you summarize it, you have a router, you have ten networks coming from either side. 16:04.950 --> 16:05.250 Yep. 16:06.240 --> 16:08.550 Ten Network is coming as summarized network from here. 16:08.760 --> 16:10.540 Ten Network is going as summarized. 16:10.590 --> 16:12.300 This is the reason we would need this, not. 16:13.430 --> 16:15.950 No, not because of that. 16:16.220 --> 16:17.590 See, right now, this will work. 16:17.600 --> 16:18.770 This is not a problem. 16:19.730 --> 16:20.420 This is not. 16:20.450 --> 16:20.660 Why? 16:20.690 --> 16:22.010 Because he installs a null graph. 16:23.120 --> 16:31.340 Why would this be a problem if I'm sending from this side a packet to ten .4.4.09.4.4.0. 16:31.370 --> 16:33.880 He doesn't know where it is, but he knows that he has a summarized out. 16:33.890 --> 16:36.080 He would send it to the other side. 16:36.080 --> 16:38.570 He doesn't have 10.4, but he has ten dot zero. 16:38.570 --> 16:39.590 He will send it back. 16:40.220 --> 16:41.360 Then he would send it back. 16:41.480 --> 16:42.680 See, we have one in the middle. 16:42.680 --> 16:43.970 One another out in the middle. 16:44.180 --> 16:44.390 Yeah. 16:45.800 --> 16:47.110 He doesn't know where to code it. 16:47.170 --> 16:47.330 Right. 16:47.840 --> 16:48.380 You have ten. 16:48.500 --> 16:48.850 He's. 16:49.240 --> 16:49.820 Yeah. 16:50.150 --> 16:54.140 He doesn't know where to forward what we have R1, R2 and R3. 16:54.800 --> 16:57.280 R1 is summarizing it to ten dot zero. 16:57.290 --> 16:57.850 Yes. 16:58.040 --> 17:01.100 In R3, summarizing the same thing as ten dot something. 17:01.160 --> 17:01.310 Yeah. 17:04.190 --> 17:05.520 Router in the middle. 17:05.540 --> 17:06.410 Let's check. 17:06.500 --> 17:09.860 See when I'm giving the route, I'm giving it to this guy. 17:09.860 --> 17:11.500 I'm telling him it's ten .0.0. 17:11.540 --> 17:12.930 Who is summarizing this guy? 17:12.930 --> 17:17.250 Yeah, he's sending it to this guy telling him I'm ten .0.0 is doing the same thing. 17:17.250 --> 17:19.410 He is also semi summarizing it as turned zero. 17:19.440 --> 17:22.470 And how does the middle router would not know. 17:22.920 --> 17:25.650 Here we need this partition here. 17:25.650 --> 17:29.300 Yes in this if you have a router in the middle you would require. 17:29.310 --> 17:32.420 But the good thing about EGP is what it installs a null route. 17:32.430 --> 17:33.150 Do you remember? 17:33.320 --> 17:33.390 Yeah. 17:33.840 --> 17:39.450 So when he summarizes he has a null route installed so that if any other packet comes to him it will 17:39.450 --> 17:40.110 stop it. 17:40.620 --> 17:41.580 It will stop that route. 17:41.580 --> 17:42.000 Right. 17:42.300 --> 17:44.070 Isn't this the same that you have? 17:45.060 --> 17:47.670 No, these are two different networks. 17:48.360 --> 17:50.930 In this case, what you're doing here is these are two different networks. 17:50.940 --> 17:52.710 This is 150 and this is 172. 17:53.340 --> 17:55.380 What we are doing is same network. 17:55.890 --> 17:57.420 It's like connected to a switch. 18:01.160 --> 18:02.300 This is the same network. 18:05.890 --> 18:09.550 So whatever routes I'm giving him is summarized. 18:10.690 --> 18:12.850 Whatever I'm giving him is summarized. 18:14.410 --> 18:15.970 He knows where to send it, right? 18:17.380 --> 18:19.450 He's supposed to send him 10.2. 18:19.480 --> 18:20.500 10.3. 18:20.530 --> 18:21.470 10.4. 18:21.490 --> 18:21.910 To whom? 18:21.940 --> 18:22.510 To this guy. 18:22.810 --> 18:24.680 But he doesn't send it as 10.1, two, three. 18:24.700 --> 18:25.760 He sends it as 10.6. 18:25.770 --> 18:29.500 Same information from R1 and he's not getting the summarized information. 18:29.500 --> 18:30.820 He's getting the actual information. 18:30.970 --> 18:32.720 It's not a summary on the spokes. 18:34.420 --> 18:34.690 Here. 18:34.690 --> 18:36.370 You said auto summaries on the spokes. 18:37.600 --> 18:41.170 So when he was getting the network, he was getting it as ten .0.0.0. 18:41.470 --> 18:42.440 Here are one. 18:42.460 --> 18:44.170 The hub is not getting ten dot zero. 18:44.560 --> 18:46.270 He's getting the actual networks. 18:48.250 --> 18:48.760 The habit. 18:48.760 --> 18:50.710 You have to see. 18:51.730 --> 18:52.720 This is 10.3. 18:52.750 --> 18:53.170 Right. 18:53.560 --> 18:56.740 When it comes to the hub, it's coming in as, what, 10.3? 18:56.770 --> 18:56.950 Right. 18:57.280 --> 19:04.330 But when he's supposed to forward this 10.3 summarising it as 10.0, but he knows where to forward it 19:04.330 --> 19:04.900 to, right? 19:04.930 --> 19:05.140 Yeah. 19:05.410 --> 19:08.950 So when R4 receives it, he receives it as ten .0.0.0. 19:09.790 --> 19:10.780 Receive it from R2. 19:11.110 --> 19:12.460 Yes it will. 19:12.490 --> 19:14.980 So it has two paths now to go to 10.00. 19:15.640 --> 19:17.560 One is from R1, one is from R2. 19:18.160 --> 19:21.490 Now this is the same situation. 19:21.760 --> 19:23.110 It doesn't have to see. 19:23.380 --> 19:29.830 You have to understand that in this case, what we have, the case that you have right now would be 19:29.830 --> 19:39.910 R1 having two different paths, two different networks, R3 and R4, and both of them are connected 19:39.910 --> 19:43.420 to the network of ten .0.0.0/8. 19:43.900 --> 19:48.260 So when he forwards it out he tells him I am ten .0.0.0/8. 19:48.470 --> 19:51.200 When he forwards it here he says I am ten .0.0. 19:51.230 --> 19:52.460 Will this be a problem? 19:53.930 --> 19:55.190 It will not be a problem, right? 19:55.970 --> 19:57.450 Because he has two paths. 19:57.470 --> 19:59.750 You can either go this side or you can go that side. 20:00.050 --> 20:01.040 It's not a problem. 20:02.630 --> 20:07.680 This network actually will be ten .1.1.11.2.2.2 or something like that. 20:07.700 --> 20:10.340 He will summarize it and send it out as ten .0/8. 20:10.610 --> 20:12.800 Now he's getting it from two different directions. 20:13.460 --> 20:15.590 Two different guys, two different next hops. 20:16.700 --> 20:17.510 Not a problem. 20:17.510 --> 20:21.260 He will load balance some traffic will send this way, some traffic he'll send the other way. 20:23.030 --> 20:23.780 Different scenario. 20:23.780 --> 20:24.140 Right. 20:24.170 --> 20:25.760 That's what is happening right now. 20:25.760 --> 20:31.100 So now you have two paths, one through R1, the other one through. 20:32.750 --> 20:35.900 Both of them are giving the route so it doesn't matter for all of them. 20:35.900 --> 20:38.550 They will always have redundancy at R5. 20:38.570 --> 20:47.030 So if you go to R5 and you check your IP route, you'll see you always have redundancy at make sure 20:47.210 --> 20:52.520 that your mappings, whenever you're having a dual hub, make sure the mappings are not incomplete. 20:54.020 --> 21:00.560 Your mapping should never be incomplete because if that is incomplete, the one side goes down, he 21:00.560 --> 21:02.210 will not be able to cover. 21:04.520 --> 21:08.420 The whole purpose of this meeting was to shut it down. 21:09.410 --> 21:15.590 The hub goes down 15 seconds he will take to make sure he understands that the hub is down. 21:15.590 --> 21:17.240 But will that affect anything here? 21:18.920 --> 21:22.520 My traceroute will still work because I don't need my hub for this. 21:24.550 --> 21:24.740 Right. 21:25.630 --> 21:29.740 If I want to go to ten .5.5.5, I would require the hub. 21:34.280 --> 21:35.630 Did I forget to use the 21:39.470 --> 21:39.880 redirect? 21:39.950 --> 21:40.520 I didn't use. 21:43.560 --> 21:43.680 I. 21:52.290 --> 21:53.910 You say that the traffic was not going down? 21:54.630 --> 21:55.650 The traffic didn't go down. 21:56.880 --> 22:00.210 Traffic was still going even though the hub died and the other hub came up. 22:00.240 --> 22:01.470 Your traffic did not have a. 22:04.250 --> 22:04.640 Do have. 22:05.330 --> 22:07.610 Everything is the same between the two. 22:08.950 --> 22:11.460 These are now our tools. 22:12.870 --> 22:14.120 It has all the mappings, right? 22:14.130 --> 22:16.470 All the hub requires is the mappings. 22:18.550 --> 22:20.680 It has the mob mappings of all the spokes. 22:21.790 --> 22:26.290 It's that the request replies redirect, replies, resolution, request forwards. 22:26.320 --> 22:28.150 The resolution request resolution request forwards. 22:28.150 --> 22:31.330 The resolution request redirects to ops. 22:32.710 --> 22:40.390 When the request doesn't matter any one of the three since since the spokes are no load balancing right. 22:40.390 --> 22:41.290 One will go this way. 22:41.290 --> 22:42.040 One will go that way. 22:42.040 --> 22:42.820 One will go this way. 22:43.030 --> 22:43.510 The request. 22:45.540 --> 22:47.370 That's purely based on the routing table. 22:48.570 --> 22:49.260 Session based. 22:49.620 --> 22:50.310 Host based. 22:50.450 --> 22:50.790 Yeah. 22:51.180 --> 22:52.080 One session. 22:52.110 --> 22:52.530 Exactly. 22:56.070 --> 23:02.280 Just like it happens in IP based on IP routing, it's load balancing is purely based on. 23:03.360 --> 23:05.130 It has nothing to do with anything else. 23:06.900 --> 23:07.470 Is this clear? 23:08.920 --> 23:10.930 Everyone play, right? 23:11.740 --> 23:12.460 Dual Hub. 23:13.150 --> 23:14.470 Tomorrow we'll do OSPF.