WEBVTT 1 00:00.180 --> 00:01.200 So for the validation, 2 00:01.200 --> 00:03.210 we're focusing on traffic sourced 3 00:03.210 --> 00:05.340 by this VM right here, VM number three, 4 00:05.340 --> 00:07.530 which is at 10.10.0.11, 5 00:07.530 --> 00:10.500 if it's sending traffic over to this VM right here, 6 00:10.500 --> 00:13.740 which is VM-2 at 10.20.0.20. 7 00:13.740 --> 00:15.300 And let's take a look at the questions 8 00:15.300 --> 00:16.740 we were asked to consider. 9 00:16.740 --> 00:18.878 So for question number one, 10 00:18.878 --> 00:21.780 it asked us, "On a host transport node such as ESXi-A 11 00:21.780 --> 00:24.630 or ESXi-B what command is used 12 00:24.630 --> 00:27.030 to see a distributed routing table? 13 00:27.030 --> 00:29.220 And there's a couple of different options 14 00:29.220 --> 00:32.010 because we could actually use get logical dash router WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 14 00:29.220 --> 00:32.010 because we could actually use get logical dash router 15 00:32.010 --> 00:34.710 and then the UUID and then ask for the routing table, 16 00:34.710 --> 00:36.900 or we could do a get gateway. 17 00:36.900 --> 00:39.690 So as a test of that, let's go to the command line interface 18 00:39.690 --> 00:44.690 with NSX CLI on both ESXi-A as a transport node and ESXi-B. 19 00:44.936 --> 00:47.850 Because ESXi-A and ESXi-B, 20 00:47.850 --> 00:49.410 if they both have VMs that are running 21 00:49.410 --> 00:52.380 and attached to those segments, they should both have a copy 22 00:52.380 --> 00:54.540 of that distributed router locally. 23 00:54.540 --> 00:56.550 So I have a SSH session opened up 24 00:56.550 --> 01:00.150 to ESXi-A here on the left hand, on the right, ESXi-B. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 24 00:56.550 --> 01:00.150 to ESXi-A here on the left hand, on the right, ESXi-B. 25 01:00.150 --> 01:03.480 I've also taken the next step of typing in NSX CLI 26 01:03.480 --> 01:06.420 to go to the NSX CLI on both of these hosts. 27 01:06.420 --> 01:08.820 And in my command window right here down below, 28 01:08.820 --> 01:10.140 I can type it in command and that's gonna 29 01:10.140 --> 01:12.169 be sent simultaneously 30 01:12.169 --> 01:14.550 to the NSX CLI interface here on ESXi-A 31 01:14.550 --> 01:16.560 as well as on B at the same time. 32 01:16.560 --> 01:18.720 So to see which gateways we have to, start off with, 33 01:18.720 --> 01:20.130 we could use one of two commands. 34 01:20.130 --> 01:23.310 We could use, get logical-routers, and press enter, 35 01:23.310 --> 01:24.690 and that's one way of doing it. 36 01:24.690 --> 01:28.560 So we've got this gateway with this UUID right here. 37 01:28.560 --> 01:30.450 In fact, lemme go ahead and put these horizontally WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 37 01:28.560 --> 01:30.450 In fact, lemme go ahead and put these horizontally 38 01:30.450 --> 01:32.250 so we can see more of the output. 39 01:32.250 --> 01:33.870 Alright, so here's the output where we can see more 40 01:33.870 --> 01:35.370 of it because it's wider. 41 01:35.370 --> 01:37.050 So here's the command, get logical-routers, 42 01:37.050 --> 01:40.080 that we've issued on both of these host transport nodes. 43 01:40.080 --> 01:43.380 Here's the UUID for the virtual router in our topology 44 01:43.380 --> 01:45.720 and here's the number of logical interfaces. 45 01:45.720 --> 01:47.430 That's what LIF stands for. 46 01:47.430 --> 01:50.790 They each have two IPv4 routes, and see, the routing table, 47 01:50.790 --> 01:53.310 we can type and get logical-router, space, 48 01:53.310 --> 01:54.900 then put in the UUID. 49 01:54.900 --> 01:57.402 So we'll go ahead and do that on both 50 01:57.402 --> 01:59.100 of 'em at the same time by pasting it down below, 51 01:59.100 --> 02:01.620 and then space, and typing in, forwarding, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 51 01:59.100 --> 02:01.620 and then space, and typing in, forwarding, 52 02:01.620 --> 02:02.640 and then pressing enter. 53 02:02.640 --> 02:04.740 And that's gonna show us the forwarding table 54 02:04.740 --> 02:06.360 for that specific gateway. 55 02:06.360 --> 02:08.880 And it's identical on both of our ESXi hosts 56 02:08.880 --> 02:11.490 because they both have a copy of this distributed router. 57 02:11.490 --> 02:13.260 Now another option that gives the same output 58 02:13.260 --> 02:15.930 is get gateways, and press enter. 59 02:15.930 --> 02:18.480 Again, that's very similar to the get logical-routers. 60 02:18.480 --> 02:19.440 Either way is great. 61 02:19.440 --> 02:21.870 They're migrating towards the use of gateway, 62 02:21.870 --> 02:24.150 the keyword, gateway, as opposed to logical-router. 63 02:24.150 --> 02:25.530 And furthermore, if we said get gateway 64 02:25.530 --> 02:27.330 and then we plugged in that UUID once again, 65 02:27.330 --> 02:30.210 which again is identical on both of these transport nodes WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 65 02:27.330 --> 02:30.210 which again is identical on both of these transport nodes 66 02:30.210 --> 02:32.220 and pasted it in and then did a space 67 02:32.220 --> 02:34.440 and typed in, forwarding, once again it shows 68 02:34.440 --> 02:37.530 the routing table for that gateway, for that logical router. 69 02:37.530 --> 02:39.330 So for the question, what command is used 70 02:39.330 --> 02:41.490 to see the distributed routers routing table, 71 02:41.490 --> 02:44.100 it'd be get, and then we could use logical-router 72 02:44.100 --> 02:47.610 or gateway, either way, followed by the UUID, 73 02:47.610 --> 02:49.200 and then followed by the keyword, forwarding, 74 02:49.200 --> 02:51.060 and that will show us the routing table. 75 02:51.060 --> 02:52.710 Alright, so that addresses the first question. 76 02:52.710 --> 02:53.970 Let's take a look at the next one. 77 02:53.970 --> 02:56.347 The second question says, "On a host transport node 78 02:56.347 --> 02:58.203 "such as ESXi-A or B, 79 02:58.203 --> 03:01.537 "one command is used to see the MAC address table WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 79 02:58.203 --> 03:01.537 "one command is used to see the MAC address table 80 03:01.537 --> 03:03.060 "for an overlay segment." 81 03:03.060 --> 03:05.850 So that is courtesy of the NSX Manager 82 03:05.850 --> 03:08.730 and the control plane there populating the information 83 03:08.730 --> 03:11.730 regarding all the MAC addresses that exist, for example, 84 03:11.730 --> 03:14.100 on segment 10 and a separate table, 85 03:14.100 --> 03:16.890 with all the MAC addresses that live on segment 20. 86 03:16.890 --> 03:19.050 So this goes back to our logical switching. 87 03:19.050 --> 03:21.360 And so to see that information we'd use the command, 88 03:21.360 --> 03:23.810 get logical-switch, or segment. 89 03:23.810 --> 03:25.680 They both do the same thing. 90 03:25.680 --> 03:28.410 And let's go ahead and do a demonstration of that right now 91 03:28.410 --> 03:30.630 for both segment 10 and segment 20. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 91 03:28.410 --> 03:30.630 for both segment 10 and segment 20. 92 03:30.630 --> 03:33.720 So here in our two ESXI hosts of the NSX CLI 93 03:33.720 --> 03:35.190 to see the existing segments 94 03:35.190 --> 03:37.680 that are relevant here on these two hosts, 95 03:37.680 --> 03:40.260 we can type in the command, get segments. 96 03:40.260 --> 03:41.670 And here in the output of get segments, 97 03:41.670 --> 03:43.470 it's showing us we have two segments. 98 03:43.470 --> 03:46.290 There's the VNI numbers, there's the UUIDs, 99 03:46.290 --> 03:48.930 and there's their names and they're again identical here 100 03:48.930 --> 03:50.914 on both ESXi-A and ESXi-B. 101 03:50.914 --> 03:53.820 Now another option to see the same information 102 03:53.820 --> 03:56.280 would be the command, get logical-switches. 103 03:56.280 --> 03:58.585 So we'll type in, get logical-switches, press enter, 104 03:58.585 --> 04:00.750 and that'll give us the same output. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 104 03:58.585 --> 04:00.750 and that'll give us the same output. 105 04:00.750 --> 04:02.850 And then furthermore, if we wanna see the MAC address table 106 04:02.850 --> 04:05.430 associated with either of these segments, 107 04:05.430 --> 04:07.080 we can type in, get segment, 108 04:07.080 --> 04:09.990 and let's take a look at the MAC address table 109 04:09.990 --> 04:11.460 for Segment 20 Pink. 110 04:11.460 --> 04:13.800 So I'm gonna go ahead and just copy that VNI, 111 04:13.800 --> 04:15.060 paste it down here below 112 04:15.060 --> 04:17.190 and then follow it up with mac-table, 113 04:17.190 --> 04:19.500 and that will show us the MAC address table 114 04:19.500 --> 04:22.230 for all the VMs associated and active now 115 04:22.230 --> 04:24.870 on that logical broadcast domain, 116 04:24.870 --> 04:28.890 in our case it's segment 20, which has the VNI of 73728. 117 04:28.890 --> 04:30.000 So we'll press enter, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 118 04:30.000 --> 04:31.770 and here's the MAC address table information, 119 04:31.770 --> 04:33.600 and lemme go ahead and put this side by side. 120 04:33.600 --> 04:35.970 So here's the command we just issued regarding 121 04:35.970 --> 04:39.540 that specific segment, 73728, which is our pink segment. 122 04:39.540 --> 04:41.400 So here in the output of get segment, 123 04:41.400 --> 04:42.660 and this is the VNI number, 124 04:42.660 --> 04:43.950 our virtual network identifier, 125 04:43.950 --> 04:46.830 for the pink segment followed by mac-table, 126 04:46.830 --> 04:49.170 is showing us MAC addresses, layer two addresses 127 04:49.170 --> 04:50.040 and how they're reachable. 128 04:50.040 --> 04:52.878 So in the case of ESXi-A, if it needed to reach 129 04:52.878 --> 04:56.910 this MAC address right here ending in C9 D3, 130 04:56.910 --> 04:57.930 it knows that MAC address 131 04:57.930 --> 04:59.610 for this segment is reachable 132 04:59.610 --> 05:02.460 through this tunnel endpoint, 22.22.22.22. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 132 04:59.610 --> 05:02.460 through this tunnel endpoint, 22.22.22.22. 133 05:02.460 --> 05:04.890 So if we needed to forward frame to that, specifically, 134 05:04.890 --> 05:06.900 to the address, ESXi-B would say, you know what, 135 05:06.900 --> 05:09.030 I'm gonna encapsulate the data and ship it over 136 05:09.030 --> 05:11.182 through the tunnel to 22.22.22.22, 137 05:11.182 --> 05:13.710 which is the tunnel endpoint for ESXi-B. 138 05:13.710 --> 05:16.170 And over here on ESXi-B it knows that if it needs 139 05:16.170 --> 05:19.200 to forward traffic to this MAC address ending in 5D AC, 140 05:19.200 --> 05:20.730 that it would go ahead and forward it 141 05:20.730 --> 05:23.130 to the tunnel endpoint 11.11.11.11, et cetera, 142 05:23.130 --> 05:24.510 and that address is the tunnel endpoint 143 05:24.510 --> 05:26.490 over here for ESXi-A. 144 05:26.490 --> 05:29.250 So that's all courtesy of the control plane 145 05:29.250 --> 05:32.880 that's being managed and maintained by our NSX Manager WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 145 05:29.250 --> 05:32.880 that's being managed and maintained by our NSX Manager 146 05:32.880 --> 05:35.760 and being kept up to date on these two transport nodes. 147 05:35.760 --> 05:37.470 So that answers question number two here. 148 05:37.470 --> 05:38.550 We can use the command, get, 149 05:38.550 --> 05:41.880 either get segment, the VNI number and mac-table, 150 05:41.880 --> 05:44.430 or we can use the command, get logical-switch, 151 05:44.430 --> 05:47.460 with the UUID number followed by the option MAC table 152 05:47.460 --> 05:50.400 to see the MAC address table for a given overlay segment. 153 05:50.400 --> 05:51.990 So then we move on to question number three, 154 05:51.990 --> 05:54.690 and that's asking us which device would make 155 05:54.690 --> 05:59.010 the routing decisions for packets from VM-3 over here 156 05:59.010 --> 06:02.070 that are being sent over to VM-2 over here? WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 156 05:59.010 --> 06:02.070 that are being sent over to VM-2 over here? 157 06:02.070 --> 06:04.260 So these two VMs are on two different hosts 158 06:04.260 --> 06:06.270 and they're on two different subnets. 159 06:06.270 --> 06:08.820 So who would make the routing decision for that? 160 06:08.820 --> 06:10.890 And a great way to verify that packet flow is to go 161 06:10.890 --> 06:12.720 to Traceflow and take a look. 162 06:12.720 --> 06:14.460 So let's go to the graphical user interface 163 06:14.460 --> 06:16.410 on the NSX Manager and we'll ask it, 164 06:16.410 --> 06:18.360 Hey, can you tell us about reachability, 165 06:18.360 --> 06:20.280 first of all, from VM-3 to VM-2, 166 06:20.280 --> 06:22.605 and as a result of that output, it'll also confirm 167 06:22.605 --> 06:24.870 who is making the routing decisions 168 06:24.870 --> 06:26.640 and what we'd expect to have happen. 169 06:26.640 --> 06:29.730 Because ESXi-A is closest to the source for VM-3, 170 06:29.730 --> 06:32.550 it should be making all the routing decisions logically WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 170 06:29.730 --> 06:32.550 it should be making all the routing decisions logically 171 06:32.550 --> 06:35.700 through the gateway between subnet 1010 172 06:35.700 --> 06:37.110 and subnet 1020, 173 06:37.110 --> 06:39.647 which are being used on segment 10 and segment 20. 174 06:39.647 --> 06:42.750 So let's head over to the NSX Manager and verify that. 175 06:42.750 --> 06:44.460 So here in the NSX Manager, 176 06:44.460 --> 06:47.550 we'll go to the Plan & Troubleshoot tab right there, 177 06:47.550 --> 06:50.220 and on the left we'll click on traffic analysis. 178 06:50.220 --> 06:51.720 And then here in the window for Traceflow, 179 06:51.720 --> 06:53.280 we'll click on Get Started. 180 06:53.280 --> 06:56.460 And if we wanna trace the traffic from VM-3 as a source, 181 06:56.460 --> 06:59.340 we'll simply go ahead and select VM-3 right there. 182 06:59.340 --> 07:02.460 And for the target, we want the target to be VM-2, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 182 06:59.340 --> 07:02.460 And for the target, we want the target to be VM-2, 183 07:02.460 --> 07:03.907 so we'll select VM-2. 184 07:03.907 --> 07:05.040 We're also gonna scroll down a little bit 185 07:05.040 --> 07:07.920 and just confirm the actual IP addresses involved 186 07:07.920 --> 07:09.900 and also make a note of the layer two address 187 07:09.900 --> 07:11.400 for the target, which is VM-2. 188 07:11.400 --> 07:13.455 So VM-2 is at 10.20.0.20, 189 07:13.455 --> 07:16.184 and there's this MAC address ending in 5D AC. 190 07:16.184 --> 07:18.540 So we'll go ahead and click on Trace 191 07:18.540 --> 07:21.690 and that'll actually inject the traffic for this test, 192 07:21.690 --> 07:23.130 and it also give us the results 193 07:23.130 --> 07:24.540 of did it make it or did it not, 194 07:24.540 --> 07:26.820 and it also gives us the logical path it took. 195 07:26.820 --> 07:28.680 So I'm gonna go ahead and collapse the left side here 196 07:28.680 --> 07:30.420 to give us a little bit more room. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 196 07:28.680 --> 07:30.420 to give us a little bit more room. 197 07:30.420 --> 07:33.000 And just for a moment, lemme go ahead and take this topology 198 07:33.000 --> 07:34.440 and make it full screen. 199 07:34.440 --> 07:35.460 Let me rearrange a little bit 200 07:35.460 --> 07:37.298 to make it a little bit bigger. 201 07:37.298 --> 07:38.131 Fantastic. 202 07:38.131 --> 07:39.420 So here's where the traffic started. 203 07:39.420 --> 07:40.740 It went through the yellow segment, 204 07:40.740 --> 07:42.330 went through the logical router, 205 07:42.330 --> 07:43.710 went down through the pink segment, 206 07:43.710 --> 07:45.750 and then finally it was delivered here to VM-2. 207 07:45.750 --> 07:47.670 So if we click right here on this icon for the host, 208 07:47.670 --> 07:49.410 it'll show us which host is involved initially. 209 07:49.410 --> 07:50.490 So this is ESXi-B, 210 07:50.490 --> 07:52.920 which is the compute resource for that VM. 211 07:52.920 --> 07:53.753 Fantastic. 212 07:53.753 --> 07:57.210 And as the traffic went through the segment 10 yellow, 213 07:57.210 --> 07:59.295 it was also ESXi-B logically moving 214 07:59.295 --> 08:01.380 the traffic through that segment. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 214 07:59.295 --> 08:01.380 the traffic through that segment. 215 08:01.380 --> 08:04.350 And then if we click here on the host icon that's associated 216 08:04.350 --> 08:07.560 with the gateway function, it's once again ESXi-B 217 08:07.560 --> 08:09.630 that's now making the routing decision 218 08:09.630 --> 08:11.730 between the 1010 network over here 219 08:11.730 --> 08:14.163 and the 1020 network over here. 220 08:14.163 --> 08:16.020 And then we go down further down through the pink subnet. 221 08:16.020 --> 08:19.560 This is also still the job of ESXi-B. 222 08:19.560 --> 08:21.810 So that's its complete routing decision. 223 08:21.810 --> 08:24.240 And at this point, ESXi-B said, you know what, 224 08:24.240 --> 08:27.180 I need to forward this over to the tunnel endpoint 225 08:27.180 --> 08:29.280 which has ownership or responsibility 226 08:29.280 --> 08:31.050 for the MAC address I'm trying to reach, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 226 08:29.280 --> 08:31.050 for the MAC address I'm trying to reach, 227 08:31.050 --> 08:33.120 at which point ESXi-B encapsulated the traffic, 228 08:33.120 --> 08:36.540 sent it through the tunnel over to ESXi-A 229 08:36.540 --> 08:37.650 who de-encapsulated it 230 08:37.650 --> 08:39.570 and then forwarded on to the final VM. 231 08:39.570 --> 08:42.330 We can verify that last piece here by clicking on the icon 232 08:42.330 --> 08:46.290 of the host next to VM-2, which shows this is ESXi-A 233 08:46.290 --> 08:47.700 who did the final delivery. 234 08:47.700 --> 08:51.120 So the routing was all done logically by the device closest 235 08:51.120 --> 08:54.930 to the source, which is ESXi-B, and then the final traffic 236 08:54.930 --> 08:58.350 was delivered to host A who then delivered that to the VM. 237 08:58.350 --> 09:00.510 If we press escape, we can also verify that WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 237 08:58.350 --> 09:00.510 If we press escape, we can also verify that 238 09:00.510 --> 09:02.280 in the output right here, 239 09:02.280 --> 09:04.740 which logically shows the traffic going 240 09:04.740 --> 09:07.620 through ESXi-B, being logically routed, 241 09:07.620 --> 09:09.840 and then right here showing that traffic being sent 242 09:09.840 --> 09:12.653 through the tunnel from ESXi-B over to ESXi-A, 243 09:12.653 --> 09:16.380 and then ESXi-A received it and then forward it to the VM. 244 09:16.380 --> 09:17.550 So for question number three, 245 09:17.550 --> 09:19.230 which device would make the routing decisions 246 09:19.230 --> 09:22.140 for the packets from VM-3 to VM-2, 247 09:22.140 --> 09:24.450 it's gonna be the transport node closest to the source, 248 09:24.450 --> 09:26.695 and in our topology that is our host transport node 249 09:26.695 --> 09:28.607 we know and love as ESXi-B 250 09:28.607 --> 09:30.990 that made those routing decisions. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 250 09:28.607 --> 09:30.990 that made those routing decisions. 251 09:30.990 --> 09:32.880 And then the fourth question we've already answered, 252 09:32.880 --> 09:33.960 but let's review it as well. 253 09:33.960 --> 09:36.750 And that is how does the device performing the IP routing, 254 09:36.750 --> 09:39.510 which is in our topology here for this traffic flow, 255 09:39.510 --> 09:42.750 ESXi-B, how does it have access to the routing table 256 09:42.750 --> 09:44.400 for the logical router? 257 09:44.400 --> 09:46.890 And the answer to that is these ESXi transport nodes 258 09:46.890 --> 09:50.160 have a living, breathing copy, if you will, 259 09:50.160 --> 09:51.510 of that distributed router. 260 09:51.510 --> 09:54.000 So ESXi-A has it, it knows all the routing 261 09:54.000 --> 09:57.390 for that logical router, and ESXi-A also has a copy 262 09:57.390 --> 10:00.150 and that's how it knows about how to route. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 262 09:57.390 --> 10:00.150 and that's how it knows about how to route. 263 10:00.150 --> 10:03.450 And that's all controlled and managed via the NSX Manager 264 10:03.450 --> 10:06.960 as it interacts and keeps these two ESXi-A hosts up to date. 265 10:06.960 --> 10:08.460 So if we add a new gateway 266 10:08.460 --> 10:10.590 or we connect a new segment to a gateway, 267 10:10.590 --> 10:12.120 we're doing that on the NSX Manager 268 10:12.120 --> 10:13.500 via the management plane, 269 10:13.500 --> 10:15.480 and then the NSX Manager is educating 270 10:15.480 --> 10:17.970 and updating all of our transport nodes that need 271 10:17.970 --> 10:19.350 that information so they can have 272 10:19.350 --> 10:21.840 that updated distributed router information as well. 273 10:21.840 --> 10:24.690 So for question number five then, after routing, 274 10:24.690 --> 10:26.430 and we're talking about ESXi-B here 275 10:26.430 --> 10:29.190 for this traffic flow, after it made the routing decision 276 10:29.190 --> 10:32.970 that the traffic sourced on segment 10 needs to be routed WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 276 10:29.190 --> 10:32.970 that the traffic sourced on segment 10 needs to be routed 277 10:32.970 --> 10:36.360 to the segment 20 before it can be delivered to this client, 278 10:36.360 --> 10:39.750 after that routing decision's done, how does ESXi-B know 279 10:39.750 --> 10:41.850 that the destination layer to address associated 280 10:41.850 --> 10:44.940 with that target is reachable, for example, over here? 281 10:44.940 --> 10:46.890 And we looked at that also earlier 282 10:46.890 --> 10:50.010 in the command line interface for NSX on each of our hosts, 283 10:50.010 --> 10:51.660 and that was looking at the actual segment. 284 10:51.660 --> 10:55.500 So for this segment right here, the NSX control plane 285 10:55.500 --> 10:58.980 provided by the NSX Manager is updating the MAC addresses 286 10:58.980 --> 11:00.840 associated with that segment. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 286 10:58.980 --> 11:00.840 associated with that segment. 287 11:00.840 --> 11:03.450 So once ESXi-B said, oh, I need to forward this 288 11:03.450 --> 11:06.870 to this layer two MAC address based on the MAC address table 289 11:06.870 --> 11:10.410 for that segment, ESXi-B knew it had to encapsulate that 290 11:10.410 --> 11:13.230 and ship it over to its good buddy, ESXi-A, 291 11:13.230 --> 11:15.840 at the tunnel endpoint of 11.11.11.11, 292 11:15.840 --> 11:18.330 at which point when ESXi-A receives that, 293 11:18.330 --> 11:20.520 it de-encapsulated it and then forwarded it directly 294 11:20.520 --> 11:23.430 to the VM-2 which owns that MAC address. 295 11:23.430 --> 11:26.220 So when it comes to forwarding traffic on an IP network, 296 11:26.220 --> 11:28.490 the first consideration is layer three, for example, 297 11:28.490 --> 11:30.630 what network do we need to forward this to WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 297 11:28.490 --> 11:30.630 what network do we need to forward this to 298 11:30.630 --> 11:31.830 from a routing perspective 299 11:31.830 --> 11:33.780 and then it's gonna be layer two. 300 11:33.780 --> 11:35.970 Now that layer two question could be, okay, 301 11:35.970 --> 11:37.770 for the next hop in this path, 302 11:37.770 --> 11:39.690 what is the layer two address for the next router, 303 11:39.690 --> 11:42.270 or in the case of our segment, segment 20, 304 11:42.270 --> 11:44.310 where ESXi-B is already connected to that, 305 11:44.310 --> 11:47.070 the layer two question is, okay, how do I reach 306 11:47.070 --> 11:48.990 that layer two address on that segment? 307 11:48.990 --> 11:51.720 So in this case, ESXi-B, knowing from the control plane 308 11:51.720 --> 11:55.530 that the MAC address for VM-2 is reachable via ESXi-A, 309 11:55.530 --> 11:58.020 that would cause ESXi-B to encapsulate the traffic, 310 11:58.020 --> 12:00.330 ship it over to ESXi-A who de-encapsulates WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 310 11:58.020 --> 12:00.330 ship it over to ESXi-A who de-encapsulates 311 12:00.330 --> 12:02.280 and then forward it to VM-2. 312 12:02.280 --> 12:03.960 So thanks for joining me in this video 313 12:03.960 --> 12:06.420 and in the skill regarding setting up 314 12:06.420 --> 12:10.740 a single virtual router as a gateway within NSX. 315 12:10.740 --> 12:13.590 And we'll have more opportunities to practice and play 316 12:13.590 --> 12:16.470 and understand IP routing in the world of NSX 317 12:16.470 --> 12:18.150 as we take a look at the next skill 318 12:18.150 --> 12:20.730 where we'll add a couple additional routers 319 12:20.730 --> 12:22.530 to do the routing and forwarding 320 12:22.530 --> 12:24.150 for not only east-west traffic, 321 12:24.150 --> 12:26.370 but also eventually for north-south traffic, 322 12:26.370 --> 12:28.680 for VMs like these guys right here 323 12:28.680 --> 12:29.760 that may need to communicate 324 12:29.760 --> 12:32.250 with external networks such as the internet WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 324 12:29.760 --> 12:32.250 with external networks such as the internet 325 12:32.250 --> 12:33.390 or other data centers. 326 12:33.390 --> 12:36.360 So I look forward to seeing you in those skills as well. 327 12:36.360 --> 12:39.000 Until then, I hope this has been informative 328 12:39.000 --> 12:41.523 and I'd like to thank you for viewing.