WEBVTT 1 00:00.000 --> 00:04.960 The primary consideration with this topology challenge is to make sure we 2 00:04.960 --> 00:06.320 remember that we 3 00:06.320 --> 00:10.970 perform load balancing in our distribution and access layers, especially 4 00:10.970 --> 00:11.560 traditional 5 00:11.560 --> 00:16.200 layer 2 ones, by making sure that our spanning tree roots are split up between 6 00:16.200 --> 00:17.200 the distribution 7 00:17.200 --> 00:24.200 switches and we align the FHRP active with those specific switches. 8 00:24.200 --> 00:27.300 Now normally we would just say all the VLens are about the same traffic so we 9 00:27.300 --> 00:27.640 're going 10 00:27.640 --> 00:31.490 to evenly divide them but this challenge did throw a little bit of a curveball WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 10 00:27.640 --> 00:31.490 to evenly divide them but this challenge did throw a little bit of a curveball 11 00:31.490 --> 00:32.840 at us. 12 00:32.840 --> 00:40.050 So let's say again that we're going to set the root to the active on the left 13 00:40.050 --> 00:40.400 and the 14 00:40.400 --> 00:46.430 root to the active on the right but we're going to do this for the odd VLens 15 00:46.430 --> 00:48.400 over here and 16 00:48.400 --> 00:51.560 the even VLens on the right. 17 00:51.560 --> 00:55.580 And to some extent that could be the end of our conversation but it was 18 00:55.580 --> 00:56.520 specifically 19 00:56.520 --> 01:04.800 called out that VLens 55 and 63 should be split up essentially. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 19 00:56.520 --> 01:04.800 called out that VLens 55 and 63 should be split up essentially. 20 01:04.800 --> 01:08.150 It was said that these were the heavy loaded VLens and we don't want both of 21 01:08.150 --> 01:08.940 them on one 22 01:08.940 --> 01:13.400 side because that will more heavily load one of the links. 23 01:13.400 --> 01:14.400 So let's split those up. 24 01:14.400 --> 01:17.560 But if we're going to split them up then we should probably move one of the 25 01:17.560 --> 01:18.560 other VLens 26 01:18.560 --> 01:21.360 over to the odd from the events. 27 01:21.360 --> 01:29.270 So maybe we just take the very first one and say I'm going to run 50 and 55 28 01:29.270 --> 01:29.600 which is an 29 01:29.600 --> 01:36.310 odd and then all the VLens on one side, 63 and all the other VLens besides 50 WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 29 01:29.600 --> 01:36.310 odd and then all the VLens on one side, 63 and all the other VLens besides 50 30 01:36.310 --> 01:37.280 on the other. 31 01:37.280 --> 01:40.900 However you divided this up is largely fine so long as we recognize sort of 32 01:40.900 --> 01:41.480 what we're 33 01:41.480 --> 01:45.120 trying to accomplish with the load balancing element. 34 01:45.120 --> 01:50.330 And the idea here is that now that we have a root and an active on one of these 35 01:50.330 --> 01:51.040 doesn't 36 01:51.040 --> 01:54.720 matter which one pick VLens 50 at this point. 37 01:54.720 --> 01:58.650 Well because of the way spanning tree works I'm going to have a better path 38 01:58.650 --> 01:59.320 this way than 39 01:59.320 --> 02:03.920 through the other switch and so I will block this link. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 39 01:59.320 --> 02:03.920 through the other switch and so I will block this link. 40 02:03.920 --> 02:07.480 Same thing with this switch will block this link. 41 02:07.480 --> 02:10.860 And this will ensure that as traffic comes in destined for the gateway that it 42 02:10.860 --> 02:11.320 arrives 43 02:11.320 --> 02:13.120 directly on the active. 44 02:13.120 --> 02:17.170 If the active was over here then we'd have to go this way to get to it which is 45 02:17.170 --> 02:18.080 inefficient. 46 02:18.080 --> 02:23.280 And so we take the most direct path to the gateways and we are ideally load 47 02:23.280 --> 02:24.280 balancing all 48 02:24.280 --> 02:28.470 of these links as best we can by dividing up the VLens and also dividing up the 49 02:28.470 --> 02:29.120 heaviest 50 02:29.120 --> 02:29.920 loaded ones.