1 00:00:00,690 --> 00:00:09,570 Before setting up our NTP service, the first thing we want to do is set our time closer to the real 2 00:00:09,570 --> 00:00:14,190 time so that NTP synchronizes quicker. At the moment 3 00:00:15,740 --> 00:00:23,420 router 2 as an example, still believes that it's in the year 2030, router 2 is in the year and 4 00:00:23,420 --> 00:00:29,960 router 3 is in the year 2002. 5 00:00:30,650 --> 00:00:39,200 Before setting time, however, we want to set a time zone and set summer time because that will affect 6 00:00:39,290 --> 00:00:45,010 the time and the devices some of the time clock and specify a time zone. 7 00:00:45,620 --> 00:00:53,720 This can be any name I'm going to specify GMT in this example, there is no hours or minutes offset 8 00:00:53,720 --> 00:00:54,920 from UTC. 9 00:00:55,460 --> 00:01:02,210 Fortunately, it's a lot simpler in the UK because Greenwich is based in the UK and other time zones 10 00:01:02,420 --> 00:01:07,070 are derived from GMT or Greenwich Meridian Time. 11 00:01:07,820 --> 00:01:14,780 If you are living in the US as an example and let's say you were on the East Coast, you might specify 12 00:01:14,780 --> 00:01:19,850 EST and the offset would be minus 5 hours. 13 00:01:20,390 --> 00:01:27,200 EST is five hours behind UTC or universal coordinated time. 14 00:01:27,860 --> 00:01:30,770 So I'm going to set GMT as my time zone 15 00:01:31,370 --> 00:01:35,060 but what I need to do now is specify summer time. 16 00:01:35,780 --> 00:01:38,090 It's summer at the moment in the UK. 17 00:01:39,700 --> 00:01:47,200 I'm going to specify a name which I'll just specify as British Summer, you can specify when summertime 18 00:01:47,200 --> 00:01:53,830 starts and stops by using either a date, which is an absolute date, or you can specify a recurring 19 00:01:53,830 --> 00:01:54,340 value. 20 00:01:54,850 --> 00:02:02,320 So I'm going to specify recurring being the last Sunday in March 21 00:02:04,140 --> 00:02:15,810 and summertime will start at 1:00 a.m. and will end in the last Sunday in October at 1:00 a.m.. 22 00:02:18,370 --> 00:02:26,110 So what you'll notice is the time is updated because it's summertime. So what I've done is 23 00:02:31,010 --> 00:02:36,680 specify the time zone and specify the summer time. 24 00:02:37,340 --> 00:02:43,730 Now, what's interesting is these two commands are done in global config on a router but the clock is 25 00:02:43,730 --> 00:02:45,650 set in privilege mode. 26 00:02:46,190 --> 00:02:55,400 So the correct time at the moment approximately is 23:19 on the 16th of August 2016. 27 00:02:56,750 --> 00:02:57,830 So show clock 28 00:03:00,090 --> 00:03:04,860 shows me that date and time now to simplify things. 29 00:03:04,890 --> 00:03:16,440 I'm going to copy and paste the clock time zone and summertime into the other routers. 30 00:03:19,400 --> 00:03:30,140 So both router 2 and router 3 are now configured with summertime and a time zone. 31 00:03:32,600 --> 00:03:36,080 So there we go, router 2, router 3 32 00:03:41,580 --> 00:03:43,020 and router 1 are configured. 33 00:03:46,980 --> 00:03:51,360 What I do need to do on both router 2 and router 3 is specify the time. 34 00:03:54,000 --> 00:03:55,370 Set it to 21 35 00:03:57,660 --> 00:04:01,980 16TH of August 2016 36 00:04:06,170 --> 00:04:08,950 and I'll do that on router 3 as well. So there's the clock 37 00:04:08,990 --> 00:04:16,029 on router 3, here's the clock on router 2 and there's the clock on router 1. 38 00:04:16,730 --> 00:04:20,630 Now, the clocks are slightly out, so that's close enough for what we're gonna do. 39 00:04:21,260 --> 00:04:25,760 What I want to do is set up router 3 now as a NTP master. 40 00:04:27,170 --> 00:04:32,360 So we would do that by using the command NTP master and specifying a stratum level. 41 00:04:32,930 --> 00:04:35,110 I'm just going to specify stratum level of ten 42 00:04:35,660 --> 00:04:44,960 and in this example, I'm going to specify the loopback as the source of time, loopbacks are good because 43 00:04:44,960 --> 00:04:47,600 once again, loopback interfaces don't go down. 44 00:04:48,470 --> 00:04:56,090 So show IP Interface brief shows me that the router has a loopback configured on quadruple 3 and I've specified 45 00:04:56,090 --> 00:05:01,280 that NTP use that as the source of time. 46 00:05:02,580 --> 00:05:11,100 So show NTP associations at the moment, the local router is associated with itself. 47 00:05:11,730 --> 00:05:14,520 This is just a loopback address on the local router 48 00:05:15,210 --> 00:05:22,710 as we can see, it's configured and at the moment it's synchronized with the master. 49 00:05:23,100 --> 00:05:27,150 In other words, itself, show NTP status. 50 00:05:30,820 --> 00:05:37,870 We can see that the clock is synchronized with a stratum 10 device, which is the local device, show 51 00:05:37,870 --> 00:05:43,060 NTP status on router 2 shows us that NTP is not enabled. 52 00:05:43,930 --> 00:05:49,750 So we could use the command NTP server and point it to router 3 53 00:05:51,980 --> 00:05:55,370 and now we can use the command show NTP status. 54 00:05:56,730 --> 00:05:58,800 At the moment, the clock is unsynchronized. 55 00:06:00,030 --> 00:06:10,350 The local stratum is 16, it has no reference clock show NTP associations, it has now associated with 56 00:06:10,390 --> 00:06:11,210 quadruple three. 57 00:06:11,880 --> 00:06:14,960 You can see that it is synchronized. 58 00:06:15,570 --> 00:06:17,590 So let's look at status again. 59 00:06:18,210 --> 00:06:18,770 There you go. 60 00:06:18,780 --> 00:06:19,920 The clock is synchronized. 61 00:06:20,400 --> 00:06:25,770 The local router has a stratum of 11 because we configured 62 00:06:29,580 --> 00:06:36,960 router 3 with a stratum of 10, the reference device is quadruple 3 we can see what the time is 63 00:06:37,380 --> 00:06:43,440 and we can see that we are using British summertime. On router 1 show NTP status, 64 00:06:46,010 --> 00:06:53,860 NTP is not configured, what I'll do here, however, is tell this router to get its time from router 2 not 65 00:06:53,870 --> 00:06:57,140 router 3. So router 3 got a stratum of 10 66 00:06:57,320 --> 00:06:58,790 this will have a stratum of 11 67 00:06:59,210 --> 00:07:01,130 and this will have a stratum of 12. 68 00:07:01,550 --> 00:07:08,600 Router 1 is getting time from router 2 and router 2 is getting time from router 3, so NTP server 2. 69 00:07:08,600 --> 00:07:13,640 2.2.2 show NTP status. 70 00:07:16,200 --> 00:07:17,910 Clock is still unsynchronized. 71 00:07:19,880 --> 00:07:24,020 Let's look at associations at the moment it's configured 72 00:07:26,200 --> 00:07:27,460 but it's not synchronized. 73 00:07:28,830 --> 00:07:36,510 But there you go, it's now synchronized with the master device, so if we look at the status, we can 74 00:07:36,510 --> 00:07:38,040 see that the clock is synchronized. 75 00:07:38,670 --> 00:07:40,920 Stratum is now 12 as expected, 76 00:07:41,250 --> 00:07:43,680 reference device is router 2. 77 00:07:45,070 --> 00:07:46,630 So show clock, 78 00:07:48,400 --> 00:07:58,390 show clock, we can see that the time is very close between these devices, just depends how quickly 79 00:07:58,390 --> 00:07:59,140 I can type 80 00:08:01,050 --> 00:08:08,700 but we can see that the time is good on the devices, the time is very close. 81 00:08:09,480 --> 00:08:15,450 So notice 11:25, 11:25, 11:25 which is great. 82 00:08:16,750 --> 00:08:22,390 Seconds are a little bit odd because I'm typing a bit slow, but you can see that they're very close 83 00:08:22,390 --> 00:08:23,050 to one another. 84 00:08:23,530 --> 00:08:26,290 So that's an example of how to set up an NTP server 85 00:08:26,500 --> 00:08:34,870 and NTP clients that receive time from an NTP server router 2 is acting as an NTP client and 86 00:08:35,080 --> 00:08:36,220 and NTP server.