0 1 00:00:00,870 --> 00:00:10,310 Cisco IOS (originally Internetwork 1 2 00:00:10,390 --> 00:00:11,950 operating system. 2 3 00:00:11,960 --> 00:00:20,770 is a family of software used on most Cisco Systems routers and current Cisco network switches.(Earlier switches ran CatOS.) 3 4 00:00:20,910 --> 00:00:30,890 IOS is a package of routing, switching, internetworking and telecommunications functions integrated 4 5 00:00:30,950 --> 00:00:34,470 into multitasking operating system. 5 6 00:00:34,760 --> 00:00:37,680 And let's take a look to the IOS features. 6 7 00:00:37,680 --> 00:00:43,010 Cisco IOS is located in flash 7 8 00:00:43,070 --> 00:00:55,560 Can be updated Copied to valotile RAM Provides software – hardware communication 8 9 00:00:55,650 --> 00:01:06,450 The Cisco IOS command-line interface (CLI) is the primary user interface used for configuring, monitoring, 9 10 00:01:06,540 --> 00:01:15,040 and maintaining Cisco devices. CLI can be accessed using ; 10 11 00:01:15,210 --> 00:01:21,060 Console Telnet SSH AUX 11 12 00:01:21,330 --> 00:01:31,350 Every Cisco router or a switch has a console port (also known 12 13 00:01:31,350 --> 00:01:35,580 as the management port) on its back side. 13 14 00:01:35,640 --> 00:01:46,620 As in here Console port is used to connect a computer directly to a router or switch and manage 14 15 00:01:46,620 --> 00:01:49,200 the router or switch since there is no display 15 16 00:01:49,200 --> 00:01:50,470 device for 16 17 00:01:50,490 --> 00:01:53,480 or switch . Normally router 17 18 00:01:53,520 --> 00:01:54,740 Console port 18 19 00:01:54,780 --> 00:02:00,720 is a RJ45 port. A special type of cable, 19 20 00:02:00,720 --> 00:02:12,490 known as roll over cable is used to connect the Serial/COM port of the computer to the router 20 21 00:02:12,580 --> 00:02:24,030 or switch console port. One end of the cable is RJ49 type and a DB9 to RJ45 21 22 00:02:24,040 --> 00:02:27,660 converter is molded on the other end. 22 23 00:02:27,770 --> 00:02:33,610 And let's go with the telnet, an access method to CLI. 23 24 00:02:33,830 --> 00:02:41,860 Telnet is a protocol that allows you to connect to remote devices over a  network. Using telnet 24 25 00:02:41,860 --> 00:02:44,440 client software on your computer, 25 26 00:02:44,590 --> 00:02:49,530 you can make a connection to a remote device. In most cases, 26 27 00:02:49,550 --> 00:02:57,970 you'll need to log into the remote host, which requires that you have an account on that system. By default, 27 28 00:02:58,270 --> 00:03:07,420 telnet does not encrypt any data sent over the connection including passwords. Because of serious security 28 29 00:03:07,420 --> 00:03:08,220 concerns. 29 30 00:03:08,230 --> 00:03:22,380 it is recommended to use SSH instead of Telnet.SSH, also known as Secure Shell, is a network 30 31 00:03:22,440 --> 00:03:30,980 that provides administrators with a secure way to access a remote networking device. Secure 31 32 00:03:31,000 --> 00:03:39,090 Shell provides strong authentication and secure encrypted data communication between two network 32 33 00:03:39,150 --> 00:03:40,270 devices 33 34 00:03:40,440 --> 00:03:45,400 Because of that it is always preferred over Telnet. 34 35 00:03:48,370 --> 00:03:58,620 Terminal emulation programs are Used for accessing to a device using console port, telnet or SSH. 35 36 00:03:58,870 --> 00:04:08,920 Popular programs are ; Putty Secure CRT Hyper Terminal 36 37 00:04:08,920 --> 00:04:16,810 Here is Putty window, if you want to for example communicate to a device you enter 37 38 00:04:16,810 --> 00:04:25,810 the host name or the IP address of the device and you choose the connection type in here whether its 38 39 00:04:26,140 --> 00:04:30,960 Telnet, SSH ,serial etc. 39 40 00:04:31,030 --> 00:04:41,310 Then you click the open and communicate with device. 40 41 00:04:41,430 --> 00:04:52,260 IOS has four different mod guys and they are ; User EXEC Privileged Global Configuration specific configuration 41 42 00:04:52,380 --> 00:05:03,450 User EXEC Mode is the first mode a user has access to 42 43 00:05:03,480 --> 00:05:11,290 after logging into the router. The user mode can be identified by the > 43 44 00:05:11,350 --> 00:05:14,930 prompt following the router name. 44 45 00:05:15,210 --> 00:05:23,460 This mode allows the user to execute only the basic commands, such as those that show the system's status.  45 46 00:05:23,730 --> 00:05:34,410 Privileged mode mode allows users to view the system configuration, restart 46 47 00:05:34,500 --> 00:05:40,000 the system, and enter router configuration mode. Privileged mode 47 48 00:05:40,140 --> 00:05:42,980 also allows all the commands 48 49 00:05:42,980 --> 00:05:50,710 that are available in user mode 49 50 00:05:51,060 --> 00:06:00,600 Global Configuration mode mode allows users to modify the running system configuration 50 51 00:06:00,690 --> 00:06:10,530 this mod has various submodes, starting with global configuration mode, and they are known as specific 51 52 00:06:10,650 --> 00:06:17,950 configuration modes.If you want to navigate between defferent IOS modes 52 53 00:06:17,990 --> 00:06:28,790 We have some options, for example if you're in the user exec mode and want to navigate to 53 54 00:06:29,120 --> 00:06:34,580 privilege exec mode we're using the Enable command. 54 55 00:06:34,830 --> 00:06:44,510 If you're in the Enable mode and if you want to switch to the config mod we're using the conf t 55 56 00:06:44,520 --> 00:06:52,270 configure terminal command and we're in the global config 56 57 00:06:52,300 --> 00:07:00,880 And if you want to switch to your specific interface configuration mode for example you type interface 57 58 00:07:00,970 --> 00:07:11,380 and the interfaces name on the config mode basically and you get into the config interface mode. Note : 58 59 00:07:11,650 --> 00:07:17,680 exit command is used for passing to the upper mode always. 59 60 00:07:17,700 --> 00:07:26,810 So let's take a look to the IOS features . IOS provides context sensitive help. 60 61 00:07:26,900 --> 00:07:33,560 Please keep in mind that question mark is your best friend always. 61 62 00:07:33,590 --> 00:07:42,020 All right let's take a look to the screen and let's say that we are trying to type clock set command 62 63 00:07:42,770 --> 00:07:44,810 instead of typing clock 63 64 00:07:44,840 --> 00:07:55,370 If I type for example C L O and k Ios is warning us and saying ask that this is an unknown command 64 65 00:07:55,380 --> 00:08:03,740 for example. for example if you could not remember the commands clock 65 66 00:08:03,800 --> 00:08:14,330 But if you just remind CL if you type C L and put a question mark IOS shows you the commands 66 67 00:08:14,330 --> 00:08:23,990 that you can use in that IOS mode. for example if you type clock the command is right now. 67 68 00:08:24,060 --> 00:08:24,990 it is OK. 68 69 00:08:25,070 --> 00:08:33,960 And if you just hit the enter it again warns you that that is an incomplete command because we're 69 70 00:08:33,980 --> 00:08:41,130 going to use the clock set as you know for example after cloak and you type. 70 71 00:08:41,150 --> 00:08:49,970 The question mark and hit enter it's showing us that what commands more we can use after that command 71 72 00:08:50,180 --> 00:08:58,390 for example it's offering us the set command and giving us some clues what the command is doing rightly. 72 73 00:08:58,430 --> 00:09:05,110 And it's saying that set the time and they for example. 73 74 00:09:05,250 --> 00:09:09,130 So let's go ahead with the context sensitive help 74 75 00:09:09,150 --> 00:09:12,830 And for example we type clock set 75 76 00:09:12,930 --> 00:09:26,130 And the clock for example, then if we had the question mark again, it's also saying us that we can use the 76 77 00:09:26,130 --> 00:09:31,640 day of the month or we can type month. 77 78 00:09:31,770 --> 00:09:35,020 keyword, All right clock set 78 79 00:09:35,070 --> 00:09:44,150 ... 79 80 00:09:44,940 --> 00:09:58,320 ... 80 81 00:09:58,410 --> 00:10:04,030 ... 81 82 00:10:04,050 --> 00:10:12,690 ... 82 83 00:10:12,690 --> 00:10:16,690 ... 83 84 00:10:18,050 --> 00:10:26,480 And we have some shortcuts and hotkeys that we can use in IOS. 84 85 00:10:26,480 --> 00:10:29,750 ... 85 86 00:10:29,750 --> 00:10:36,560 ... 86 87 00:10:36,560 --> 00:10:42,710 .... 87 88 00:10:42,710 --> 00:10:51,750 ... 88 89 00:10:54,600 --> 00:11:02,590 ... 89 90 00:11:02,680 --> 00:11:13,630 .. 90 91 00:11:13,940 --> 00:11:21,690 ... 91 92 00:11:21,770 --> 00:11:28,750 ... 92 93 00:11:28,960 --> 00:11:29,700 ... 93 94 00:11:29,830 --> 00:11:35,440 ... 94 95 00:11:35,440 --> 00:11:42,870 ... 95 96 00:11:42,880 --> 00:11:47,400 ... 96 97 00:11:48,780 --> 00:11:55,820 ... 97 98 00:11:55,820 --> 00:11:59,970 ... 98 99 00:11:59,970 --> 00:12:05,130 ... 99 100 00:12:05,160 --> 00:12:11,690 ... 100 101 00:12:11,700 --> 00:12:24,050 ... 101 102 00:12:24,070 --> 00:12:25,090 ... 102 103 00:12:25,180 --> 00:12:30,610 ... 103 104 00:12:30,670 --> 00:12:38,670 ... 104 105 00:12:38,770 --> 00:12:44,370 ... 105 106 00:12:44,560 --> 00:12:54,000 ... 106 107 00:12:54,130 --> 00:12:58,950 ... 107 108 00:12:59,050 --> 00:13:08,680 ... 108 109 00:13:09,550 --> 00:13:19,140 ... 109 110 00:13:19,240 --> 00:13:28,920 ... 110 111 00:13:29,110 --> 00:13:35,660 ... 111 112 00:13:35,690 --> 00:13:46,030 ... 112 113 00:13:46,030 --> 00:13:48,210 ... 113 114 00:13:48,230 --> 00:13:52,560 ... 114 115 00:13:52,590 --> 00:14:07,870 ... 115 116 00:14:07,890 --> 00:14:08,670 ... 116 117 00:14:08,670 --> 00:14:12,420 ... 117 118 00:14:12,450 --> 00:14:14,980 ... 118 119 00:14:15,850 --> 00:14:23,560 ... 119 120 00:14:23,710 --> 00:14:32,180 ... 120 121 00:14:32,290 --> 00:14:37,730 ... 121 122 00:14:38,620 --> 00:14:43,580 ... 122 123 00:14:43,670 --> 00:14:49,470 ... 123 124 00:14:49,490 --> 00:14:51,740 ... 124 125 00:14:53,630 --> 00:15:03,380 If you want to encrypt all your passwords in your show run output we have a great command. we can use 125 126 00:15:03,590 --> 00:15:06,820 service password encryption. 126 127 00:15:06,830 --> 00:15:15,970 This command to encrypt all passwords on the show run out for example in here. 127 128 00:15:15,970 --> 00:15:25,550 ... 128 129 00:15:25,640 --> 00:15:33,170 ... 129 130 00:15:33,500 --> 00:15:37,390 ... 130 131 00:15:37,410 --> 00:15:46,760 ... 131 132 00:15:46,910 --> 00:15:50,060 ... 132 133 00:15:50,210 --> 00:15:53,500 ... 133 134 00:15:53,720 --> 00:15:57,300 ... 134 135 00:15:57,350 --> 00:16:02,370 ... 135 136 00:16:04,660 --> 00:16:07,750 ... 136 137 00:16:07,900 --> 00:16:17,500 ... 137 138 00:16:17,500 --> 00:16:18,470 ... 138 139 00:16:18,730 --> 00:16:28,720 ... 139 140 00:16:28,810 --> 00:16:32,760 ... 140 141 00:16:32,800 --> 00:16:44,170 ... 141 142 00:16:44,170 --> 00:16:53,870 ... 142 143 00:16:54,180 --> 00:16:59,970 ... 143 144 00:16:59,970 --> 00:17:10,360 ... 144 145 00:17:10,360 --> 00:17:13,490 ... 145 146 00:17:13,990 --> 00:17:25,850 ... 146 147 00:17:25,850 --> 00:17:30,750 ... 147 148 00:17:30,860 --> 00:17:33,070 ... 148 149 00:17:33,140 --> 00:17:45,650 ... 149 150 00:17:45,710 --> 00:17:55,900 ... 150 151 00:17:56,090 --> 00:18:04,910 ... 151 152 00:18:04,910 --> 00:18:14,180 ... 152 153 00:18:14,180 --> 00:18:20,340 ... 153 154 00:18:20,540 --> 00:18:23,340 ... 154 155 00:18:23,350 --> 00:18:31,150 .... 155 156 00:18:31,460 --> 00:18:39,170 ... 156 157 00:18:39,340 --> 00:18:47,760 ... 157 158 00:18:47,770 --> 00:18:57,390 ... 158 159 00:18:57,690 --> 00:19:07,950 ... 159 160 00:19:08,010 --> 00:19:11,540 ... 160 161 00:19:11,610 --> 00:19:15,450 ...