1 00:00:00,000 --> 00:00:03,500 [VIDEO LOGO] 2 00:00:03,500 --> 00:00:13,000 3 00:00:13,000 --> 00:00:16,000 So now, let's jump into trouble ticket 2. 4 00:00:16,000 --> 00:00:19,870 This one again is going to be on OSPF topology 3. 5 00:00:19,870 --> 00:00:23,830 But this time, we're looking towards router 5. 6 00:00:23,830 --> 00:00:28,180 It says router 5 currently has no OSPF routes 7 00:00:28,180 --> 00:00:29,870 in its routing table. 8 00:00:29,870 --> 00:00:33,520 So we're going to have to jump over here and look at router 5. 9 00:00:33,520 --> 00:00:35,620 Looking at our diagram, it looks like we're 10 00:00:35,620 --> 00:00:38,560 going to be basically troubleshooting between router 11 00:00:38,560 --> 00:00:40,210 5 and router 4. 12 00:00:40,210 --> 00:00:42,940 So we'll check to see if router 4 has routes 13 00:00:42,940 --> 00:00:44,860 and that sort of thing as well, but it 14 00:00:44,860 --> 00:00:46,930 seems like the problem is generally 15 00:00:46,930 --> 00:00:48,520 going to be in this area. 16 00:00:48,520 --> 00:00:49,600 Maybe not. 17 00:00:49,600 --> 00:00:52,030 Maybe router 4 doesn't have the routes either. 18 00:00:52,030 --> 00:00:54,640 But let's just go ahead and check the situation here 19 00:00:54,640 --> 00:00:58,920 and see what this situation looks like. 20 00:00:58,920 --> 00:01:01,910 So let's start here on router 5, verifying the ticket. 21 00:01:01,910 --> 00:01:04,340 Let's just do a show IP route OSPF. 22 00:01:04,340 --> 00:01:06,720 And well, we can see that we do, in fact, 23 00:01:06,720 --> 00:01:10,220 have no routes in the routing table on router 5. 24 00:01:10,220 --> 00:01:13,370 So let's see if we have a neighborship with router 4. 25 00:01:13,370 --> 00:01:15,690 We said that that might be an issue. 26 00:01:15,690 --> 00:01:18,410 So let's do a show IP OSPF neighbor. 27 00:01:18,410 --> 00:01:21,390 And as we can see, we have no neighbors either. 28 00:01:21,390 --> 00:01:24,780 So this appears to be another neighborship issue. 29 00:01:24,780 --> 00:01:28,730 So let's also take a look at our show IP OSPF interface brief. 30 00:01:28,730 --> 00:01:31,040 And here we see a situation where 31 00:01:31,040 --> 00:01:34,250 it appears that we only have our loopback 0 32 00:01:34,250 --> 00:01:37,460 interface in the OSPF process. 33 00:01:37,460 --> 00:01:40,520 Now, just to expand on this show IP OSPF interface 34 00:01:40,520 --> 00:01:44,060 brief a little bit or show some alternatives, 35 00:01:44,060 --> 00:01:48,980 there's also show OSPF interface brief. 36 00:01:48,980 --> 00:01:51,260 But we need to be a little bit careful here. 37 00:01:51,260 --> 00:01:56,000 Notice that this is showing me gigabit 2 and loopback 0, 38 00:01:56,000 --> 00:02:00,230 but these are actually for the address family IPv6. 39 00:02:00,230 --> 00:02:04,670 If you actually say show OSPF question mark, what we're 40 00:02:04,670 --> 00:02:09,229 actually typing is show OSPFv3. 41 00:02:09,229 --> 00:02:16,130 So what's interesting about this is if I were to say show OSPF-- 42 00:02:16,130 --> 00:02:20,030 and by the way, there's a choice here for IPv4. 43 00:02:20,030 --> 00:02:24,440 But if I say IPv4 interface brief, 44 00:02:24,440 --> 00:02:27,020 this still won't show our interfaces 45 00:02:27,020 --> 00:02:34,640 because this would be OSPF version 3 IPv4 enabled 46 00:02:34,640 --> 00:02:35,850 interfaces. 47 00:02:35,850 --> 00:02:39,110 Now, if we were to change IPv4 to IPv6. 48 00:02:39,110 --> 00:02:42,110 Well, this is the same command we typed earlier essentially. 49 00:02:42,110 --> 00:02:44,450 We just left out the IPv6. 50 00:02:44,450 --> 00:02:48,350 So this will show us the IPv6 enabled interfaces 51 00:02:48,350 --> 00:02:53,780 or more specifically, the OSPFv3 enabled interfaces. 52 00:02:53,780 --> 00:02:55,670 But again, in our case, we're trying 53 00:02:55,670 --> 00:02:58,760 to run OSPF version 2 for this and we 54 00:02:58,760 --> 00:03:01,850 don't have any interfaces enabled for IPv4 55 00:03:01,850 --> 00:03:04,400 for OSPF version 3 anyway. 56 00:03:04,400 --> 00:03:07,020 57 00:03:07,020 --> 00:03:09,780 But this brings us back to the fundamental problem 58 00:03:09,780 --> 00:03:16,110 that gigabit 2 is, in fact, not enabled for OSPF version 2. 59 00:03:16,110 --> 00:03:19,600 So this is what we're going to need to fix. 60 00:03:19,600 --> 00:03:22,990 Now, this is another situation where we have a couple of ways 61 00:03:22,990 --> 00:03:24,460 that we could fix this. 62 00:03:24,460 --> 00:03:26,800 We could, of course, use a network statement 63 00:03:26,800 --> 00:03:30,340 under the OSPF process or we could enable it 64 00:03:30,340 --> 00:03:31,900 under the interface. 65 00:03:31,900 --> 00:03:34,870 I personally generally prefer to configure it 66 00:03:34,870 --> 00:03:36,160 under the interface. 67 00:03:36,160 --> 00:03:39,320 It's a little bit more exact, a little more precise control. 68 00:03:39,320 --> 00:03:41,600 So that's what we'll go ahead and do. 69 00:03:41,600 --> 00:03:44,370 So we'll simply go into interface, gigabit 2. 70 00:03:44,370 --> 00:03:48,300 We'll say IP OSPF 1 area 0. 71 00:03:48,300 --> 00:03:51,550 Exit configuration. 72 00:03:51,550 --> 00:03:53,570 Let's look at our interfaces again. 73 00:03:53,570 --> 00:03:57,310 We see that now gigabit 2 is, in fact, 74 00:03:57,310 --> 00:03:59,740 enabled for OSPF version 2. 75 00:03:59,740 --> 00:04:03,050 We also see out here it's listing a neighbor, 76 00:04:03,050 --> 00:04:06,220 so let's verify that as well. 77 00:04:06,220 --> 00:04:08,440 We do our show IP OSPF neighbor. 78 00:04:08,440 --> 00:04:11,950 We see that, in fact, neighbor 4 is now up. 79 00:04:11,950 --> 00:04:14,850 And if we do a show IP route OSPF, 80 00:04:14,850 --> 00:04:20,940 we see that we now have a couple routes in our routing table. 81 00:04:20,940 --> 00:04:25,140 Now, again, the routing table isn't real populous just yet. 82 00:04:25,140 --> 00:04:26,930 We have just the two routes. 83 00:04:26,930 --> 00:04:29,250 But before, we had none. 84 00:04:29,250 --> 00:04:31,580 So this should be the problem that was being 85 00:04:31,580 --> 00:04:33,080 referenced in this ticket. 86 00:04:33,080 --> 00:04:35,690 It really looks like we solved it because we do now 87 00:04:35,690 --> 00:04:38,090 have routes on router 5. 88 00:04:38,090 --> 00:04:41,630 So here, we saw an example of simply not having 89 00:04:41,630 --> 00:04:45,890 the correct interfaces enabled for the correct protocol. 90 00:04:45,890 --> 00:04:47,960 I hope this has been informative for you, 91 00:04:47,960 --> 00:04:51,070 and I'd like to thank you for viewing. 92 00:04:51,070 --> 00:04:54,000