1 00:00:06,490 --> 00:00:11,230 So on the subnet 1 9 2 1 6 8 1 128 slash 26. 2 00:00:11,260 --> 00:00:16,030 We've been told to configure the router with the last IP address in the subnet. 3 00:00:16,030 --> 00:00:19,000 Now the next subnet is 192 4 00:00:19,030 --> 00:00:27,070 so the broadcast address for the subnet will be 191 which means that this router can be configured with 5 00:00:27,070 --> 00:00:28,810 190 6 00:00:28,810 --> 00:00:31,970 Have a look at the previous videos in this series. 7 00:00:32,049 --> 00:00:40,860 If you're not sure how I worked that out, so IP address 192 168 1, 192 is the next subnet 1 8 00:00:40,860 --> 00:00:49,720 91 is the broadcast, 190 is the last IP address in the subnet, subnet mask is that and we know 9 00:00:49,720 --> 00:00:58,310 that from our previous calculations, the switch needs to use the second IP address in the subnet. The 10 00:00:58,310 --> 00:01:08,720 router is configured with 190 so the switch, I'll change the name to switch 2 we'll simply use IP address 11 00:01:09,010 --> 00:01:18,660 192 168 1 189 so 1 less than the router 12 00:01:21,290 --> 00:01:26,680 no shut the interface so ping 192 168 1 189. 13 00:01:26,940 --> 00:01:28,770 That's our local IP address. 14 00:01:28,770 --> 00:01:30,680 Can we ping the router? 15 00:01:30,780 --> 00:01:32,360 Yes, we can. 16 00:01:32,360 --> 00:01:43,680 I'll also configure a default gateway on the switch pointing to the router, switch is configured, so the 17 00:01:43,680 --> 00:01:47,160 switch once again is using 189. 18 00:01:47,160 --> 00:01:49,930 The DNS server should use 188 19 00:01:53,150 --> 00:02:02,330 one less than the switch, so static IP address of the DHCP server is 192 168 188 subnet mask is 255 20 00:02:02,360 --> 00:02:16,340 255 255 192, default gateway is the router 192 168 1 190 again that's the IP address of the router DNS 21 00:02:16,360 --> 00:02:18,680 server will be Google. 22 00:02:19,050 --> 00:02:26,890 So on the server, can we ping the router, type that right. 23 00:02:27,920 --> 00:02:29,120 Yes, we can. 24 00:02:29,120 --> 00:02:31,910 Can we ping the switch? 25 00:02:31,910 --> 00:02:33,380 Yes, we can. 26 00:02:33,380 --> 00:02:33,860 Can we 27 00:02:33,860 --> 00:02:37,630 ping the DNS server? 28 00:02:37,760 --> 00:02:43,540 Not at the moment because we need to configure the serial interface of the router. 29 00:02:43,670 --> 00:02:52,970 But now let's configure the DHCP server, so DHCP I'll enable the DHCP service default gateway is gonna 30 00:02:52,970 --> 00:03:03,110 be 192 so 1, so 192 168 1 190 DNS server is Google, IP addresses that we'll allocate 31 00:03:03,360 --> 00:03:06,230 are 192 168 1. 32 00:03:06,230 --> 00:03:07,760 Now you need to be careful. 33 00:03:07,880 --> 00:03:13,750 The first host is one more than the subnet, so it's 129. 34 00:03:14,210 --> 00:03:15,460 Maximum number of hosts 35 00:03:15,470 --> 00:03:19,670 I'll allocate is 50 and I'll save that configuration. 36 00:03:19,880 --> 00:03:24,490 You could allocate more IP addresses in your pool or less if you wanted to so. 37 00:03:24,530 --> 00:03:29,990 So for instance only allocate 10, just depends how many IP addresses in your subnet you want to have 38 00:03:30,470 --> 00:03:32,040 for static IP addresses. 39 00:03:32,120 --> 00:03:41,930 How many IP addresses you want for dynamic IP addresses. So on the PC, IP config, IP address has been 40 00:03:41,930 --> 00:03:42,770 allocated. 41 00:03:42,950 --> 00:03:46,560 Ping 192 168 1 190. 42 00:03:46,640 --> 00:03:48,320 That's the router, 43 00:03:48,320 --> 00:03:51,880 that's the switch, that's the DNS server. 44 00:03:51,950 --> 00:03:53,480 What about PC 5 45 00:03:53,540 --> 00:03:55,160 just do one more here. 46 00:03:55,340 --> 00:03:59,830 IP config, IP address has been allocated. 47 00:03:59,990 --> 00:04:02,680 So can we ping the router? 48 00:04:03,260 --> 00:04:04,430 Yes, we can. 49 00:04:04,430 --> 00:04:06,320 What about switch? 50 00:04:06,350 --> 00:04:07,670 Yes, we can. 51 00:04:07,670 --> 00:04:09,710 What about DNS server? 52 00:04:09,710 --> 00:04:10,960 Yes, we can. 53 00:04:11,000 --> 00:04:15,490 We won't be able to ping 192 168 1.1 54 00:04:15,680 --> 00:04:22,910 PC in the other subnet because we still need to configure this serial link, so let's configure the 55 00:04:22,910 --> 00:04:31,820 serial link the IP address of this router on the serial interface is gonna be one more than the subnet. 56 00:04:34,100 --> 00:04:36,520 So show IP interface brief. 57 00:04:36,830 --> 00:04:47,060 This serial interface needs to be configured with IP address 192 168 1 subnet is 192. 58 00:04:47,060 --> 00:04:53,390 So, first IP address will be 193 with that subnet mask. 59 00:04:53,510 --> 00:04:57,170 So can we ping 192 168 1 193. 60 00:04:57,170 --> 00:05:04,730 It won't work at this point because we need to configure the other side. So on this router show IP interface 61 00:05:04,730 --> 00:05:12,770 brief we still need to configure the zero interface it's currently down, so no shut that. IP address 62 00:05:12,770 --> 00:05:21,950 will be 192 168 1 and this is a little bit more difficult to work out the broadcast for the subnet. 63 00:05:22,160 --> 00:05:31,610 Again you just populate the host portion with binary ones and what you'll notice is it's full of ones. 64 00:05:31,820 --> 00:05:39,320 So that would equal 255, so one less than the broadcast is 254. 65 00:05:39,320 --> 00:05:49,380 So 254 subnet mask is that no shut the interface again so show IP interface brief according to this 66 00:05:49,380 --> 00:05:51,570 it's still down. 67 00:05:51,590 --> 00:05:54,800 Let's make sure that I've configured it right. 68 00:05:54,800 --> 00:05:56,480 Show IP interface brief, 69 00:06:00,250 --> 00:06:07,320 I may have connected the wrong serial interface in this network and that looks like what I've done, wrong 70 00:06:07,320 --> 00:06:08,970 serial interface. 71 00:06:09,090 --> 00:06:12,120 So what I'll do is delete that serial interface. 72 00:06:12,120 --> 00:06:15,060 I'll fix it in your lab so you don't have that problem. 73 00:06:16,470 --> 00:06:27,120 That serial should be connected to that serial, so show IP interface brief this interface is up up 74 00:06:27,810 --> 00:06:31,120 so can we ping 192 168 1 254 75 00:06:31,170 --> 00:06:31,920 Yes, we can. 76 00:06:32,430 --> 00:06:41,040 So router 2 can ping the Internet router, so hopefully, these PCs can now ping the Internet which 77 00:06:41,040 --> 00:06:49,650 they can, notice they can ping cisco.com as an example and they can ping facebook.com. 78 00:06:49,650 --> 00:06:57,540 So going to the web browser on PC 3, can this PC get to cisco.com? 79 00:06:57,540 --> 00:06:58,950 Yes, it can. 80 00:06:58,980 --> 00:07:00,930 Can it get to facebook.com? 81 00:07:00,930 --> 00:07:02,400 Yes, it can. 82 00:07:02,400 --> 00:07:07,470 What about PC 5, web browser on PC 5. 83 00:07:07,470 --> 00:07:09,570 Can we get to cisco.com? 84 00:07:09,570 --> 00:07:10,950 Yes, we can. 85 00:07:10,950 --> 00:07:13,120 Can we get to facebook.com? 86 00:07:13,140 --> 00:07:14,290 Yes, we can. 87 00:07:14,340 --> 00:07:17,820 We can access these servers on the Internet. 88 00:07:17,910 --> 00:07:21,150 We've had to do quite a lot here, as a last test. 89 00:07:21,150 --> 00:07:29,640 Can the PCs in the 1 subnet ping PCs in the other subnet, so can we ping 192 168 1. 90 00:07:29,640 --> 00:07:30,310 1? 91 00:07:30,360 --> 00:07:31,080 Yes, we can. 92 00:07:31,410 --> 00:07:32,700 What about 1.2? 93 00:07:32,700 --> 00:07:33,990 Yes, we can. 94 00:07:33,990 --> 00:07:43,440 And if we trace to that, we are essentially sending traffic to router 2 then to the Internet router 95 00:07:43,770 --> 00:07:48,890 then to router 1 and then to the PC in the other subnet. 96 00:07:49,120 --> 00:07:54,250 Okay, so this was quite a complex lab we had to do a lot of things here, but I'm hoping it's helped you 97 00:07:54,250 --> 00:08:01,620 understand subnetting and way you use subnetting and how to use subnetting in a practical lab.