{"id":1990,"date":"2019-06-21T18:03:31","date_gmt":"2019-06-21T18:03:31","guid":{"rendered":"http:\/\/wiki.thomasandsofia.com\/?p=1990"},"modified":"2020-05-06T11:57:46","modified_gmt":"2020-05-06T11:57:46","slug":"section-4-the-cisco-ios-operating-system","status":"publish","type":"post","link":"https:\/\/wiki.thomasandsofia.com\/?p=1990","title":{"rendered":"Section 4: The Cisco IOS Operating System"},"content":{"rendered":"<p><a href=\"http:\/\/wiki.thomasandsofia.com\/?p=1980\">&lt; Section 3<\/a> | <a href=\"\/course-introduction\/\">Home<\/a> | <a href=\"http:\/\/wiki.thomasandsofia.com\/?p=2002\">Section 5 &gt;<\/a><\/p>\n<h1>17. Introduction<\/h1>\n<p><a href=\"https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589308#questions\" target=\"_blank\" rel=\"noopener\">https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589308#questions<\/a><\/p>\n<h1>18. Cisco Operating Systems<\/h1>\n<p><a href=\"https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589310#questions\" target=\"_blank\" rel=\"noopener\">https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589310#questions<\/a><\/p>\n<p>Not required for the Exam<\/p>\n<ul>\n<li>Cisco started with Routers in 1984<\/li>\n<li>IOS is the OS<\/li>\n<li>Original OS was CatOS<\/li>\n<\/ul>\n<h2>NEW Operating Systems<\/h2>\n<ul>\n<li>NX-OS: Cisco Nexus and MDS data center swietch products<\/li>\n<li>IOS-XR: NCS, CRS, ASR9000 and XR12000 series routers<\/li>\n<li>ISO-XE: ASR1000 series routers<\/li>\n<li>Command line for these are nearly identical to IOS<\/li>\n<\/ul>\n<h1>19. Making the initial connection to a Cisco device<\/h1>\n<p><a href=\"https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589312#questions\">https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589312#questions<\/a><\/p>\n<ul>\n<li>For day to day management, you&#8217;ll use SSH (Secure Shell) to connect to the management IP<\/li>\n<li>For enterprise networks, secure login will typically be enforced through integration with a centralised AAA (Authentication, Authorization and Accounting) server.<\/li>\n<li>Cisco devices do not have a default IP, so one needs to be setup.<\/li>\n<li>To setup the initial IP, you&#8217;ll need to console the device\n<ul>\n<li>Requires a special console cable.<\/li>\n<li>Connects to your serial port and to the devices with an RJ-45 connector<\/li>\n<li>Since most computers do not include a serial port anymore, you&#8217;ll need a USB to Serial port adapter.\n<ul>\n<li>This will require a driver before it will work<\/li>\n<\/ul>\n<\/li>\n<li>Newer Cisco devices now come with a special USB to Mini USB cable.\n<ul>\n<li>You&#8217;ll still need a drive<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>Connecting with Putty<\/h2>\n<ul>\n<li>Select &#8216;Serial&#8217; connection<\/li>\n<li>Speed: 9600 baud<\/li>\n<li>Serial Line: Com1 (or whatever com port you&#8217;re using.)<\/li>\n<\/ul>\n<p>Why use the Console Cable<\/p>\n<ul>\n<li>Initial configuration<\/li>\n<li>Required if the devices IP becomes unresponsive\n<ul>\n<li>Stolen?<\/li>\n<\/ul>\n<\/li>\n<li>Can be used to troubleshoot the boot process.\n<ul>\n<li>You can view the device booting from the console connection<\/li>\n<li>You cannot do this via SSH since the system must be booted prior to connecting<\/li>\n<\/ul>\n<\/li>\n<li>Can be used for Out of Band Management\n<ul>\n<li>This is where you use a different path (other than production network) to connect to the device for management.<\/li>\n<li>if you have an issue with the Production network, you can still access the router or switch\n<ul>\n<li>This is usually accomplished using a Terminal Server that is often another router.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h1>20. Navigating the Cisco IOS Operating System Part 1<\/h1>\n<p><a href=\"https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589316#questions\" target=\"_blank\" rel=\"noopener\">https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589316#questions<\/a><\/p>\n<p>Initial Boot:<\/p>\n<pre>Would you like to enter the initial configuration dialog? [yes\/no]: no\r\nWould you like to terminat autoinstall? [yes\/no] : yes<\/pre>\n<p>After boot, you&#8217;ll be in User Exec mode.<\/p>\n<h2>User Exec mode<\/h2>\n<pre>Router&gt;<\/pre>\n<ul>\n<li>Designated by &#8216;Hostname&gt;&#8217;<\/li>\n<li>Very limited commands available<\/li>\n<li>Press &#8216;?&#8217; to see a list of available commands<\/li>\n<li>&#8212;More&#8212; means there are additional commands to see\n<ul>\n<li>[Enter] Scroll line by line<\/li>\n<li>[ _ ] (Space) scroll page by page.\n<ul>\n<li>Recommended to set Putty scroll back to 2000<\/li>\n<\/ul>\n<\/li>\n<li>Press [Ctrl] [C] to stop scrolling<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>Privileged Exec mode<\/h2>\n<pre>Router&gt;enable\r\nRouter#<\/pre>\n<ul>\n<li>aka &#8216;The Enable prompt&#8217;<\/li>\n<li>Type &#8216;enable&#8217; to access\n<ul>\n<li>Type &#8216;disable&#8217; to return to User Exec mode<\/li>\n<\/ul>\n<\/li>\n<li>Designated by &#8216;Hostname#&#8217;<\/li>\n<\/ul>\n<h3>Using command abbreviation<\/h3>\n<ul>\n<li>Enter the first few characters of the command.\u00a0 If a unique match is found, you can just use it.\n<ul>\n<li>enable = &#8216;en&#8217;<\/li>\n<\/ul>\n<\/li>\n<li>if a unique command is not found:\n<ul>\n<li>ex: &#8216;di&#8217;<\/li>\n<li>Ambiguous command: &#8216;di&#8217;<\/li>\n<li>Press &#8216;?&#8217; to see a list of possible matching commands<\/li>\n<li>Continue typing until you&#8217;re reached a unique string that can only apply to the command you&#8217;re looking for.<\/li>\n<\/ul>\n<\/li>\n<li>To finds options for a specific command\n<ul>\n<li>Type the command (or unique abbreviation) [ _ ] [ ? ]\n<ul>\n<li>show ?<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li>press [Tab] to auto complete a command.<\/li>\n<li>If the list of commands ends with &lt;cr&gt; (Carriage Return) any other commands are optional.<\/li>\n<\/ul>\n<h4>Difference between &#8216;show&#8217; and &#8216;debug&#8217;<\/h4>\n<ul>\n<li>Show will show the current state as you pressed [Enter]<\/li>\n<li>Debug will continue to update as changes are encountered.<\/li>\n<\/ul>\n<h2>Global Configuration mode<\/h2>\n<pre>Router configure terminal\r\nRouter(config)#<\/pre>\n<ul>\n<li>Abbreviation: &#8216;conf t&#8217;<\/li>\n<\/ul>\n<h1>21. Navigating the Cisco IOS Operating System Part 2<\/h1>\n<p><a href=\"https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589318#questions\" target=\"_blank\" rel=\"noopener\">https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589318#questions<\/a><\/p>\n<h2>Command History<\/h2>\n<p>[Ctrl] buttons are a bit messed up with minicom usb adaptor!<\/p>\n<ul>\n<li>[ UpArrow ] &#8211; Previous command\n<ul>\n<li>Only shows commands for the current &#8216;exec&#8217; mode.<\/li>\n<\/ul>\n<\/li>\n<li>[ Ctrl ] [A] &#8211; Start of the line<\/li>\n<li>[ Ctrl ] [Z] &#8211; End of line<\/li>\n<\/ul>\n<p>To run Privilege Exec commands at the Global Configuration mode<\/p>\n<ul>\n<li>do (rest of command)\n<ul>\n<li>do show ip interface brief<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Global Configuration level is used to configure items globally.\u00a0 To edit specific items, you must first enter their mode&#8230;<\/p>\n<pre>Router(config)#interface fastethernet 0\/0\r\nRouter(config-if)#<\/pre>\n<p>To return back to Global Config level<\/p>\n<ul>\n<li>exit<\/li>\n<\/ul>\n<pre>Router(config-if)#exit\r\nRouter(config)#exit\r\nRouter#exit\r\nRouter&gt;<\/pre>\n<p>To drop all the way back to the Privileged Exec mode<\/p>\n<ul>\n<li>end<\/li>\n<\/ul>\n<pre>Router(config-if)#end\r\nRouter#<\/pre>\n<h2>Most Common Commands<\/h2>\n<h3>show ip interface brief<\/h3>\n<ul>\n<li>Shows all interfaces on the router<\/li>\n<li>State of the interface (up or down)<\/li>\n<li>IP address configured on the interface.<\/li>\n<\/ul>\n<h3>show running-config<\/h3>\n<ul>\n<li>Shows the entire configuration on the router<\/li>\n<li>Several pages of data.<\/li>\n<\/ul>\n<p>There are filters to only show specific sections of the running config.<\/p>\n<h4>show run int fast 0\/0<\/h4>\n<ul>\n<li>only shows the config for Interface FastEthernet 0\/0<\/li>\n<\/ul>\n<p>Reg Ex<\/p>\n<ul>\n<li>show run | begin hostname\n<ul>\n<li>starts from the first line that has hostname<\/li>\n<\/ul>\n<\/li>\n<li>show run | include host\n<ul>\n<li>shows all lines that include the word host<\/li>\n<li>show run | include Host\n<ul>\n<li>Fails!\u00a0 This is case sensitive!!<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li>show run | exclude interface\n<ul>\n<li>show all lines excluding interface<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>show startup-config<\/h3>\n<ul>\n<li>Shows the configuration loaded at boot time.<\/li>\n<li>Changes to the running config must be saved here, or they will all be lost on next reboot.<\/li>\n<\/ul>\n<h3>copy running-config startup-config<\/h3>\n<ul>\n<li>Copies the running config to the startup configuration.<\/li>\n<\/ul>\n<h3>copy run flash:&lt;filename&gt;<\/h3>\n<ul>\n<li>Copies the running config to flash disk space.<\/li>\n<\/ul>\n<h3>show flash<\/h3>\n<ul>\n<li>Displays files on the flash drive.<\/li>\n<\/ul>\n<h3>reload<\/h3>\n<ul>\n<li>Reboot the router<\/li>\n<\/ul>\n<h1>22. Cisco IOS Configuration Management<\/h1>\n<p>https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589322#questions<\/p>\n<h2>Configuring the Router<\/h2>\n<ul>\n<li>Any changes made go into effect immediately and are recorded in the running-config.<\/li>\n<li>These changes are NOT saved to the start up config unless you explicitly copy them there.<\/li>\n<\/ul>\n<pre>Router&gt;enable\r\nRouter#configure terminal\r\nRouter(config)#<\/pre>\n<p>Set the hostname<\/p>\n<pre>Router(config)#hostname r1\r\nr1(config)#<\/pre>\n<h3>copy running-config startup-config<\/h3>\n<ul>\n<li>Copies the running config to the startup configuration.<\/li>\n<\/ul>\n<h3>copy run flash:&lt;filename&gt;<\/h3>\n<ul>\n<li>Copies the running config to flash disk space.<\/li>\n<\/ul>\n<h3>show flash<\/h3>\n<ul>\n<li>Displays files on the flash drive.<\/li>\n<\/ul>\n<h4>To restore the running config \/ startup config from the flash backup<\/h4>\n<ul>\n<li>Erase the startup config\n<ul>\n<li>#erase start<\/li>\n<\/ul>\n<\/li>\n<li>Copy the back up to the new startup\n<ul>\n<li>copy flash:&lt;filename&gt; startup-config<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>File Storage Locations<\/h2>\n<ul>\n<li>IOS is stored in Flash<\/li>\n<li>Startup Config in NVRAM\n<ul>\n<li>Persistent across reboots<\/li>\n<\/ul>\n<\/li>\n<li>Running Config in RAM\n<ul>\n<li>Loaded from the running config during boot<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h1>23. Lab Exercises<\/h1>\n<p><a href=\"http:\/\/wiki.thomasandsofia.com\/wp-content\/uploads\/2019\/06\/04-The-IOS-Operating-System-Lab-Exercises.pdf\">04 The IOS Operating System &#8211; Lab Exercises<\/a><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>&lt; Section 3 | Home | Section 5 &gt; 17. Introduction https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589308#questions 18. Cisco Operating Systems https:\/\/www.udemy.com\/cisco-icnd1\/learn\/lecture\/8589310#questions Not required for the Exam Cisco started with Routers in 1984 IOS is the OS Original OS was CatOS NEW Operating Systems NX-OS: Cisco Nexus and MDS data center swietch products IOS-XR: NCS, CRS, ASR9000 and XR12000 series ..<\/p>\n<div class=\"clear-fix\"><\/div>\n<p><a href=\"https:\/\/wiki.thomasandsofia.com\/?p=1990\" title=\"read more...\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[45],"tags":[],"class_list":["post-1990","post","type-post","status-publish","format-standard","hentry","category-icnd1-ccent"],"_links":{"self":[{"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=\/wp\/v2\/posts\/1990","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1990"}],"version-history":[{"count":9,"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=\/wp\/v2\/posts\/1990\/revisions"}],"predecessor-version":[{"id":2853,"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=\/wp\/v2\/posts\/1990\/revisions\/2853"}],"wp:attachment":[{"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1990"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1990"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wiki.thomasandsofia.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1990"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}