WEBVTT 00:09.060 --> 00:15.190 Hello friends welcome back in this section we're going to talk about different ways to protest or do 00:15.190 --> 00:15.690 so. 00:15.700 --> 00:18.910 OK we're going to learn different ways to protect our work. 00:18.910 --> 00:23.240 So we're against hacker attacks or against an art that is Rexus. 00:23.360 --> 00:23.860 OK. 00:24.250 --> 00:31.450 So in this lesson I'm going to show you how to set up and you have w firewall by setting up your firewall 00:31.450 --> 00:33.390 you can't protect your server. 00:33.550 --> 00:34.020 OK. 00:34.180 --> 00:36.940 From an advisory or IP addresses. 00:36.970 --> 00:37.360 OK. 00:37.450 --> 00:41.600 Or you can allow all the connections for only particular ports. 00:41.620 --> 00:42.090 OK. 00:42.370 --> 00:46.640 So let's see practically hope to set up a new firewall. 00:47.180 --> 00:51.010 OK you know stands for uncomplicate firewall OK. 00:51.010 --> 00:54.580 It is the most popular firewall in the school. 00:54.940 --> 00:59.440 And that's why it comes by default in Linux distributions. 00:59.450 --> 00:59.930 OK. 01:00.190 --> 01:06.820 So you don't need to install in this Ubuntu server distribution by default it comes in this package 01:07.110 --> 01:13.870 only in some cases if you want to install it just takes sudo is stolen. 01:14.010 --> 01:18.170 You have to install the firewall. 01:18.460 --> 01:21.360 You can only see how to use this firewall. 01:21.850 --> 01:26.280 OK first of all you should check the status of the firewall. 01:26.560 --> 01:33.530 So check the status this type Sudol w status. 01:33.730 --> 01:34.030 OK. 01:34.060 --> 01:40.250 Right now it says actually this will shows you the current status of the blue firewall. 01:40.280 --> 01:41.130 OK. 01:42.340 --> 01:48.400 If you want to disable the firewall in some situations then you can simply disable it by sudo. 01:48.400 --> 01:52.750 You have to disable it it takes some time. 01:53.100 --> 01:53.420 OK. 01:53.440 --> 01:55.780 And not the status. 01:56.290 --> 01:58.310 OK right now it is inactive. 01:58.720 --> 02:07.230 And if you want to enable it then just type in invoke again take the status. 02:07.820 --> 02:12.860 Right now it's easy to get in this way you can disable enable the firewall. 02:12.950 --> 02:13.450 OK. 02:13.550 --> 02:17.820 In some situation you need to reload all the rules of the firewall. 02:17.870 --> 02:18.190 OK. 02:18.200 --> 02:25.500 So in those situations you just need to simply type sudo with W reload key. 02:25.560 --> 02:30.270 It didn't and now it says firewall reloaded. 02:30.350 --> 02:36.180 OK in this way you can perform these basic operations with this new firewall. 02:36.680 --> 02:44.310 The next operation that I would like to show you is how to allow calls or IP addresses from the firewall. 02:44.870 --> 02:45.380 OK. 02:45.710 --> 02:53.510 Let's talk about if you want to allow some particular ports on your server OK if you follow some connections 02:53.810 --> 02:55.170 on a particular call. 02:55.270 --> 02:55.860 OK. 02:56.130 --> 03:01.560 Then in this condition you use to type sudo if you have to do a lot. 03:01.730 --> 03:02.240 OK. 03:02.420 --> 03:06.600 And I want to allow the connections on what we're going get to. 03:06.620 --> 03:08.790 People generally used by. 03:08.930 --> 03:09.590 OK. 03:09.650 --> 03:14.670 All we learned in the last lessons about how to set up the assets is OK. 03:14.860 --> 03:18.620 So I want connections outside connections on this board. 03:18.710 --> 03:23.070 Then I can simply type like this and hit enter. 03:23.500 --> 03:24.030 OK. 03:24.330 --> 03:28.470 And after adding in this rule you can check the status. 03:29.190 --> 03:29.600 OK. 03:29.660 --> 03:32.830 After writing the rule you can see we got a different status. 03:33.020 --> 03:33.570 OK. 03:33.680 --> 03:38.430 In this way you can check the rules by status. 03:38.480 --> 03:38.980 OK. 03:39.980 --> 03:45.480 OK like the port number we can also add in particular IP address to connect on our server. 03:45.740 --> 03:51.050 So for that just helps slow if you allow from. 03:51.100 --> 03:54.690 OK if I want a connection from 1 9. 03:54.780 --> 04:01.610 Got 1 6 8 0 0 0 1 true added. 04:02.240 --> 04:04.090 Then check the status. 04:04.630 --> 04:04.950 OK. 04:04.970 --> 04:08.870 Now here you can see at line number two we have over rule. 04:09.010 --> 04:09.380 OK. 04:09.410 --> 04:17.270 That means this IP addresses are allowed on our server to connect OK like this we can't allow an particular 04:17.360 --> 04:20.840 IP address a no particular order only. 04:21.050 --> 04:21.440 OK. 04:21.530 --> 04:29.980 So what you need to do for that Sudol w love from. 04:30.770 --> 04:41.030 1 9 2 you got 1 6 8 0 1 and I want this IP address to connect only for granted. 04:41.240 --> 04:41.520 OK. 04:41.540 --> 04:53.230 So just like any port 22 this IP is allowed only on port number 22 after this rule did did the status. 04:54.090 --> 04:58.000 This way we cannot allow any IP addresses in this V. 04:58.300 --> 04:58.740 OK. 04:59.030 --> 05:00.750 And after allowing. 05:00.980 --> 05:04.740 We can also deny support or IP addresses. 05:05.030 --> 05:08.440 So you deny in particular for just pipes. 05:08.480 --> 05:10.860 You have to keep the key. 05:10.940 --> 05:16.550 And if I want to deny Port Authority or give partner we're used to private service we're talking all 05:16.550 --> 05:20.000 we have learned in the previous lesson. 05:20.010 --> 05:22.250 He to OK. 05:22.280 --> 05:26.940 He says really did exist sturgeons. 05:27.050 --> 05:27.730 OK. 05:29.900 --> 05:33.540 And you can also deny in particular IP. 05:33.590 --> 05:44.110 So for that just the night from 1 9 4 1 6 0 1 0 0 0 Google kid. 05:45.630 --> 05:47.440 His rule added means. 05:47.450 --> 05:54.640 Suppose there is some hacker who was trying to hack a server and then you can grab that hackers IP address 05:54.640 --> 06:00.700 and you can block that hacker from connecting to a surrogate by this one. 06:01.030 --> 06:01.560 OK. 06:01.690 --> 06:08.260 Alavi and denying the IP and port numbers I want to show you how good the lead the rules that we have 06:08.470 --> 06:09.680 added. 06:10.090 --> 06:14.930 So there are movies by which you can delete the rules in the firewall. 06:15.010 --> 06:17.750 OK number one is with the help off number. 06:18.130 --> 06:19.960 And number two is Vittal off. 06:19.990 --> 06:20.590 Come on. 06:20.710 --> 06:21.010 OK. 06:21.010 --> 06:23.700 So let's see how you do this. 06:23.750 --> 06:30.710 OK first just type sudo status number one. 06:31.080 --> 06:35.020 OK get this view uses the numbers for each room. 06:35.050 --> 06:35.360 OK. 06:35.380 --> 06:39.190 So the numbers from 1 to 7 for each rule. 06:39.280 --> 06:39.780 OK. 06:40.060 --> 06:41.740 And I want to delete. 06:41.740 --> 06:44.770 Rule number two here so read that. 06:44.810 --> 06:55.660 So you have to delete and enter the number here in Atlanta to my Ok it is related. 06:55.660 --> 06:57.680 Again take the status. 06:57.990 --> 07:02.470 Now we have only six rules here with six numbers. 07:02.680 --> 07:03.250 OK. 07:03.430 --> 07:06.700 This is the first mail by which we can delete it rule. 07:06.910 --> 07:07.220 OK. 07:07.250 --> 07:12.950 The second way is from common means so you need to know how you entered the command. 07:12.940 --> 07:13.550 OK. 07:13.990 --> 07:21.630 So to delete I suppose who'll hear sudo if you get delete. 07:21.720 --> 07:22.630 You need to type that. 07:22.630 --> 07:29.670 Come on I mean suppose we have added allowing port number 22 for IP address 1 9 2 and 6. 07:30.070 --> 07:38.970 So here sudo you have w delete allow from one line. 07:39.130 --> 07:41.430 Once you've got 0 1 07:45.400 --> 07:49.800 we're going to hit enter again later. 07:49.930 --> 07:53.480 This is the second way for deleting the rule in the file. 07:53.560 --> 07:56.930 Ok you need to have that come on like this. 07:57.230 --> 07:58.400 OK. 07:58.930 --> 07:59.230 OK. 07:59.230 --> 08:04.140 In this way you can add the rules or delete the rules looking in the firewall. 08:04.160 --> 08:04.700 OK. 08:04.720 --> 08:08.940 All this depends on your requirement for a server. 08:09.160 --> 08:11.930 What you want to do with your server. 08:12.490 --> 08:19.660 Ok after doing all this there are some situations where you need to reset your firewall background you 08:19.680 --> 08:20.490 know status. 08:20.500 --> 08:21.160 OK. 08:21.190 --> 08:31.740 So in such situations what you need to do is just pseudo cop you can type reset and you don't get into 08:31.750 --> 08:37.500 why look at this reset the firewall back group's original status. 08:37.630 --> 08:46.540 In this way you can use this firewall and secure your Ubuntu server from that has real users OK or an 08:46.610 --> 08:48.740 authorized IP addresses.