1 00:00:00,683 --> 00:00:08,030 In the previous video, we already create topology with 2 router, now in this video we are going to 2 00:00:08,030 --> 00:00:18,886 configure ospf in this topology. The concept of ospf is same as eigrp, which is each router must 3 00:00:18,886 --> 00:00:27,170 advertise their connected network. So for example here router 1 must be have 2 connected network, 4 00:00:27,418 --> 00:00:42,032 which is 10.10.10.0/24 connected to fa0/0, and 192.168.1.0/24 connected to fa0/1. 5 00:00:44,007 --> 00:00:47,330 Router 2 must be have 2 connected network, 6 00:00:48,354 --> 00:01:00,760 10.10.10.0/24 connected to fa0/0 and 192.168.2.0/24 connected to fa0/1. 7 00:01:01,460 --> 00:01:05,928 So router 1 and router 2 must advertise 2 network. 8 00:01:06,642 --> 00:01:16,890 Let’s start configuring router 1, the command is router ospf, if we use eigrp, 9 00:01:16,890 --> 00:01:25,840 we must define autonomous system number, but in ospf, we must define ospf process id. 10 00:01:26,844 --> 00:01:28,920 Here let’s exit first. 11 00:01:30,746 --> 00:01:39,396 And then router ospf and question mark, here we can see that we need to define ospf process id. 12 00:01:40,180 --> 00:01:48,454 In the eigrp, the autonomous system number must be same on all routers, but in ospf, 13 00:01:48,580 --> 00:01:55,922 because this is only ospf process id, so the number can be different in each router. 14 00:01:56,548 --> 00:02:04,260 Let’s say in router 1, we use router ospf 1, in router 2 we use router ospf 2, 15 00:02:04,524 --> 00:02:10,238 and in router 3 we use router ospf 3, this is will work. 16 00:02:10,976 --> 00:02:17,174 Or if we use same ospf process id in all router, this is also work. 17 00:02:18,402 --> 00:02:20,930 Okay, let’s say here we use 1, 18 00:02:22,318 --> 00:02:30,996 Next we need to advertise all of connected network. Let’s advertise 10.10.10.0/24, 19 00:02:31,748 --> 00:02:43,592 so network 10.10.10.0, in the eigrp, the command is just like this and we can enter, but in ospf, 20 00:02:43,592 --> 00:02:48,586 we need to add some argument, question mark, 21 00:02:48,896 --> 00:02:51,678 Here we need to define wildcard bits, 22 00:02:52,058 --> 00:02:57,900 what is wildcard bits? Wildcard bits is the reverse of subnetmask. 23 00:02:58,458 --> 00:03:06,256 We know that for prefix /24, the subnetmask is 255.255.255.0. 24 00:03:10,000 --> 00:03:20,266 And then, to calculate wildcard bits, the formula is 255.255.255.255 minus by subnetmask. 25 00:03:20,924 --> 00:03:30,850 In this case, the prefix is /24, and the subnetmask for prefix /24 is 255.255.255.0. 26 00:03:32,390 --> 00:03:41,877 So here 255 minus by 0 is 255, 255 minus by 255 is 0, 27 00:03:41,877 --> 00:03:49,220 255 minus by 255 is 0 and 255 minus by 255 again is also 0. 28 00:03:49,894 --> 00:03:57,310 So the wildcard bits for prefix /24 is 0.0.0.255 29 00:03:59,160 --> 00:04:02,722 Okay, this is how we calculate wildcard bits. 30 00:04:07,668 --> 00:04:10,280 Now let’s back to the configuration, 31 00:04:10,854 --> 00:04:21,860 so here the wildcard bits is 0.0.0.255. And then question mark again, here we need to define area, 32 00:04:24,346 --> 00:04:32,866 and then question mark, we must define the area number. For now, let’s just use area 0. 33 00:04:33,800 --> 00:04:38,942 Okay now we have done advertise network 10.10.10.0. 34 00:04:39,512 --> 00:04:44,218 Next, let’s advertise the network that connected to pc 1. 35 00:04:44,848 --> 00:04:54,734 So here, network 192.168.1.0 0.0.0.255 area 0. 36 00:04:56,360 --> 00:05:04,440 Okay now we have done configuring ospf on router 1, next let’s configure on router 2. 37 00:05:06,172 --> 00:05:13,338 Enable, configure terminal, and then router ospf, remember that 38 00:05:13,338 --> 00:05:21,724 here we need to define ospf process id, and ospf process id doesn’t have to be same. 39 00:05:22,542 --> 00:05:29,568 In the router 1 we use process id 1, let’s say here we will use process id 2. 40 00:05:30,562 --> 00:05:43,206 Next, let’s advertise the network, network 10.10.10.0 0.0.0.255 area 0. 41 00:05:44,228 --> 00:05:58,110 Next let’s advertise the network that connected to pc 2, so network 192.168.2.0 0.0.0.255 area 0. 42 00:06:00,694 --> 00:06:05,666 Okay now we have done configuring ospf on router 1 and router 2. 43 00:06:06,016 --> 00:06:16,892 Let’s verify it, do show ip ospf neighbor, here we can see that now we have ospf neighbor, 44 00:06:17,206 --> 00:06:22,858 and the status is full. This is means that the ospf is UP. 45 00:06:24,788 --> 00:06:32,954 Let’s also check the routing table, do show ip route, here we can see that from router 2, 46 00:06:32,954 --> 00:06:43,640 we have route to 192.168.1.0/24, the label is O, this is means ospf. 47 00:06:46,388 --> 00:06:50,812 Let’s also check on router 1, do show ip route, 48 00:06:51,968 --> 00:07:01,316 here we can see that router 1 also have a route to 192.168.2.0/24 and the label is o. 49 00:07:02,002 --> 00:07:13,018 So now pc 1 and pc 2 should be able to communicate each others. Let’s try, failed, let’s test again, 50 00:07:14,608 --> 00:07:16,232 and here success. 51 00:07:16,712 --> 00:07:21,536 Okay so now we have done configuring dynamic routing ospf. 52 00:07:22,058 --> 00:07:29,520 I think enough for this video, in the next video, we are going to add 1 more router to our topology. 53 00:07:30,000 --> 00:07:33,408 Thank you for watching and see you on the next video.