WEBVTT 1 00:00.000 --> 00:04.710 Well, big takeaway from this skill should be that we understand how traffic 2 00:04.710 --> 00:05.720 flows among 3 00:05.720 --> 00:09.910 the different virtual machines that exist inside of a single virtual host or a 4 00:09.910 --> 00:10.720 hypervisor, 5 00:10.720 --> 00:16.890 and then also between different hypervisor, different vswitches, and talking to 6 00:16.890 --> 00:17.400 devices 7 00:17.400 --> 00:20.560 out on the rest of the network, including a default gateway. 8 00:20.560 --> 00:23.240 So let's go ahead and go through these challenges. 9 00:23.240 --> 00:26.770 And we need to keep in mind, first and foremost, that there is going to be pin 10 00:26.770 --> 00:27.520 ning involved 11 00:27.520 --> 00:28.800 here. 12 00:28.800 --> 00:32.030 And so we might just want to take a moment to decide where these VMs are going WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 12 00:28.800 --> 00:32.030 And so we might just want to take a moment to decide where these VMs are going 13 00:32.030 --> 00:32.360 to be 14 00:32.360 --> 00:33.360 pinned. 15 00:33.360 --> 00:37.220 Now we weren't told this, but they are going to get pinned to one of these 16 00:37.220 --> 00:37.800 links. 17 00:37.800 --> 00:40.120 Now they could both get pinned to the same link. 18 00:40.120 --> 00:42.040 That is certainly an option as well. 19 00:42.040 --> 00:45.900 So maybe we just do that here in this situation, and then VMC it could be to 20 00:45.900 --> 00:47.120 either one of these 21 00:47.120 --> 00:48.600 uplinks. 22 00:48.600 --> 00:53.080 So now that we've established the pinning, let's go through these challenges. 23 00:53.080 --> 00:57.200 So first of all, VMA sends a packet to VMB. 24 00:57.200 --> 01:00.440 So once again, we're talking about downstream switching. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 24 00:57.200 --> 01:00.440 So once again, we're talking about downstream switching. 25 01:00.440 --> 01:02.240 This is going to act like any other switch. 26 01:02.240 --> 01:06.820 It's going to directly switch and allow VMA and VMB to communicate with each 27 01:06.820 --> 01:07.760 other without 28 01:07.760 --> 01:10.560 ever sending packets off of the box. 29 01:10.560 --> 01:13.670 Now interestingly, this can be a challenge because we might have network 30 01:13.670 --> 01:14.440 monitoring up 31 01:14.440 --> 01:17.360 here, and we want to know what that traffic looks like. 32 01:17.360 --> 01:22.080 And so this can make it so we have a hard time seeing that traffic. 33 01:22.080 --> 01:23.080 But it is a reality. 34 01:23.080 --> 01:27.870 Now we could possibly set up span on the virtual switch and send information 35 01:27.870 --> 01:29.120 about that traffic 36 01:29.120 --> 01:30.280 off of the box. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 36 01:29.120 --> 01:30.280 off of the box. 37 01:30.280 --> 01:34.480 But by default, the native switching of this V switch is going to make it so 38 01:34.480 --> 01:35.160 that this 39 01:35.160 --> 01:38.520 switch up here never sees those packets. 40 01:38.520 --> 01:41.800 And so if we have security policy up here as well, that's going to get 41 01:41.800 --> 01:42.960 completely bypassed 42 01:42.960 --> 01:47.240 by the fact that again, our physical network never sees the packet, which is 43 01:47.240 --> 01:47.840 interesting, 44 01:47.840 --> 01:52.320 especially if the network team is in charge of the physical network, but the 45 01:52.320 --> 01:53.040 server team 46 01:53.040 --> 01:54.360 is in charge of this network. 47 01:54.360 --> 01:59.360 Well, that as you can imagine might cause a little bit of conflict there. 48 01:59.360 --> 02:03.350 Now moving on to the next one, virtual machine, a sent a packet to virtual WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 48 01:59.360 --> 02:03.350 Now moving on to the next one, virtual machine, a sent a packet to virtual 49 02:03.350 --> 02:04.800 machine C. Well, 50 02:04.800 --> 02:06.920 I can't bridge this gap. 51 02:06.920 --> 02:10.720 There is a air gap between the two virtual switches. 52 02:10.720 --> 02:14.010 I guess if we want to use air quotes for air gap, there we might want to do 53 02:14.010 --> 02:14.480 that. 54 02:14.480 --> 02:18.350 It's all in software after all, but we do see that there's traffic isolation 55 02:18.350 --> 02:18.880 here. 56 02:18.880 --> 02:23.710 So for a VM a to communicate to VMC, we're going to need to go off of its 57 02:23.710 --> 02:24.680 pinned link 58 02:24.680 --> 02:28.160 here or through its pinned link up to the switch. 59 02:28.160 --> 02:32.710 The switch will get will take that packet, check its cam table and see that the WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 59 02:28.160 --> 02:32.710 The switch will get will take that packet, check its cam table and see that the 60 02:32.710 --> 02:33.320 MAC address 61 02:33.320 --> 02:37.340 lives out this port, it's pinned link, and that will eventually get to virtual 62 02:37.340 --> 02:37.840 machine 63 02:37.840 --> 02:38.840 C. 64 02:38.840 --> 02:44.280 So this traffic isolation are these is going to be achieved by deploying 65 02:44.280 --> 02:46.120 multiple V switches, 66 02:46.120 --> 02:50.260 but we also get the traffic to show up on the physical switching infrastructure 67 02:50.260 --> 02:50.520 . 68 02:50.520 --> 02:55.750 So that's another way that we could do that in order to see the traffic on our 69 02:55.750 --> 02:56.520 network. 70 02:56.520 --> 02:59.280 Now next virtual machine, a sent a packet to its gateway. 71 02:59.280 --> 03:00.640 Let me change colors here. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 71 02:59.280 --> 03:00.640 Let me change colors here. 72 03:00.640 --> 03:02.040 We're trying to send to our gateway. 73 03:02.040 --> 03:04.640 Well, once again, we are going to go out our pinned link. 74 03:04.640 --> 03:06.280 We don't have any other choice here. 75 03:06.280 --> 03:08.200 That's the definition of pinning. 76 03:08.200 --> 03:11.980 So I'm going to send it up to the switch and that'll get switched over to the 77 03:11.980 --> 03:12.720 appropriate 78 03:12.720 --> 03:15.840 port and sent out to the gateway. 79 03:15.840 --> 03:17.920 And by the way, VMB would do the same thing. 80 03:17.920 --> 03:21.800 It would send out the same pinned link as we see and it would get sent to the 81 03:21.800 --> 03:22.360 gateway 82 03:22.360 --> 03:23.920 this direction. 83 03:23.920 --> 03:28.030 So we've got multiple virtual machines that can all access their default gate 84 03:28.030 --> 03:28.600 ways. 85 03:28.600 --> 03:31.600 Now lastly, virtual machine A sends a broadcast packet. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 85 03:28.600 --> 03:31.600 Now lastly, virtual machine A sends a broadcast packet. 86 03:31.600 --> 03:37.040 Our diagram is getting a little bit busy here, but if I send a broadcast packet 87 03:37.040 --> 03:37.320 now into 88 03:37.320 --> 03:39.160 the virtual switch, what happens? 89 03:39.160 --> 03:42.200 Well, a virtual switch is going to do what any other switch would do. 90 03:42.200 --> 03:48.060 It's going to send a copy of that packet to all of the other virtual machines 91 03:48.060 --> 03:48.520 that 92 03:48.520 --> 03:51.280 might be attached to that V switch. 93 03:51.280 --> 03:54.960 But notice that VMC here doesn't receive it from the V switch. 94 03:54.960 --> 03:57.000 It's not attached to that V switch. 95 03:57.000 --> 03:58.680 So does it get a copy of it? 96 03:58.680 --> 04:03.510 Well, yes, because like all these other packets, we're going to send a copy up WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 96 03:58.680 --> 04:03.510 Well, yes, because like all these other packets, we're going to send a copy up 97 04:03.510 --> 04:05.880 to our pinned 98 04:05.880 --> 04:06.960 up link. 99 04:06.960 --> 04:12.700 And so the switch is going to send that flooded traffic out all of the other 100 04:12.700 --> 04:13.520 links. 101 04:13.520 --> 04:17.000 Now is it a problem that it got sent back down to the same virtual switch? 102 04:17.000 --> 04:23.110 Well, no, because it's going to show up on a pinned link that all these other 103 04:23.110 --> 04:23.880 virtual 104 04:23.880 --> 04:26.560 machines have already received a copy of that. 105 04:26.560 --> 04:29.320 And so we're going to prevent that from happening. 106 04:29.320 --> 04:32.090 And then same thing over here, we're going to prevent this from going anywhere, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 106 04:29.320 --> 04:32.090 And then same thing over here, we're going to prevent this from going anywhere, 107 04:32.090 --> 04:32.480 but this 108 04:32.480 --> 04:35.980 one since it hits the pinned up link is going to follow the pinned up link and 109 04:35.980 --> 04:36.520 make sure 110 04:36.520 --> 04:41.410 our copy does get to virtual machine C. So what we see here is that our pinned 111 04:41.410 --> 04:42.080 traffic 112 04:42.080 --> 04:47.040 is a great way to achieve load balancing and redundancy, but it doesn't cause 113 04:47.040 --> 04:47.840 looping. 114 04:47.840 --> 04:50.850 And we don't have to run spanning tree, which is the most beautiful thing at 115 04:50.850 --> 04:51.280 all. 116 04:51.280 --> 04:54.680 Of all, now it does have to exist at the very edge of our networks. 117 04:54.680 --> 04:58.750 We can't run pinning in the middle of our networks, but because we have so many 118 04:58.750 --> 04:59.760 of these 119 04:59.760 --> 05:02.790 hypervisors and virtual hosts in our data center, as well as, like I said, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000 119 04:59.760 --> 05:02.790 hypervisors and virtual hosts in our data center, as well as, like I said, 120 05:02.790 --> 05:03.680 technology like 121 05:03.680 --> 05:04.680 UCS. 122 05:04.680 --> 05:10.240 We do see that pinning is important inside of data center networking. 123 05:10.240 --> 05:12.760 I hope this has been informative for you and I'd like to thank you for viewing.