{"id":8348,"date":"2022-07-20T12:36:55","date_gmt":"2022-07-20T10:36:55","guid":{"rendered":"https:\/\/tekmart.co.za\/t-blog\/?p=8348"},"modified":"2022-07-20T12:45:20","modified_gmt":"2022-07-20T10:45:20","slug":"upgrading-or-downgrading-the-ios-on-an-isr-or-similar-router-a-simple-how-to-step-by-step-guide","status":"publish","type":"post","link":"https:\/\/tekmart.co.za\/t-blog\/upgrading-or-downgrading-the-ios-on-an-isr-or-similar-router-a-simple-how-to-step-by-step-guide\/","title":{"rendered":"Upgrading or downgrading the IOS on an ISR (or similar) router; a simple how-to step by step guide."},"content":{"rendered":"<span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading Time-approximately:<\/span> <span class=\"rt-time\"> 2<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span>\n<h2 class=\"wp-block-heading\"><strong>You can use these steps to either upgrade or downgrade the IOS on an ISR router. We have used the Cisco 2800 Series Integrated Services Router (ISR) in this example.<\/strong><\/h2>\n\n\n\n<p><strong>By Tekmart Africa Enterprise Support<\/strong><\/p>\n\n\n\n<p><strong>First up, you must make sure you have done the following ready :<\/strong><\/p>\n\n\n\n<p>1) Get the new IOS to the router<\/p>\n\n\n\n<p>2) Verify the integrity of the new IOS binary<\/p>\n\n\n\n<p>3) Change the boot statements to ensure that the correct IOS loads after restart<\/p>\n\n\n\n<p>4) Save configuration changes<\/p>\n\n\n\n<p>5) Reload the device and verify that the correct IOS has loaded<\/p>\n\n\n\n<p><strong>Why change IOS versions:<\/strong><\/p>\n\n\n\n<p>The most frequent reasons that one would change the IOS on a router are:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>New version has new features<\/li><li>New version fixes or avoids triggering a bug<\/li><li>Security patching\/compliance (ex PCI compliance)<\/li><\/ul>\n\n\n\n<figure class=\"wp-block-pullquote alignleft has-text-align-left\"><blockquote><p><strong>Potential Caveats:<\/strong><\/p><p>Usually these would only affect older routers but the main caveats would be ensuring there is enough system memory (RAM) and also flash to store the new IOS.<\/p><\/blockquote><\/figure>\n\n\n\n<p><strong>Step 1: Get the new IOS to the router.<\/strong><\/p>\n\n\n\n<p>If you are onsite then often the simplest way to get the new IOS to the router is to copy the IOS to a flash card, or on newer ISR G2s, USB thumb drive.<\/p>\n\n\n\n<p>Otherwise you would copy the file to the router using TFTP, FTP, etc.&nbsp; Detailed instructions for this step are out of scope but an example would be:<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>copy ftp: flash:\u00a0\u00a0\u00a0<\/em>\u00a0\u00a0\u00a0 <\/strong><\/pre>\n\n\n\n<p>(Follow the prompts for server IP and file name.)<\/p>\n\n\n\n<p><strong>Step 2: Verify the integrity of the new IOS binary<\/strong><\/p>\n\n\n\n<p>The next step we take is to verify that the IOS was not corrupted during transit or copying.<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>verify flash:c2800nm-advsecurityk9-mz.150-1.M8.bin<\/em><\/strong><\/pre>\n\n\n\n<p>Success will show that the calculated MD5 hash is the same as the embedded hash.<\/p>\n\n\n\n<p><strong>Step 3: Change the boot statements to ensure that the correct IOS loads after restart<\/strong><\/p>\n\n\n\n<p>We need to remove the old boot statement(s) and add the new one.&nbsp; (There are other ways to select which IOS to run but this is the simplest method.)<\/p>\n\n\n\n<p>a. examine the current boot statement(s)<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>show run | include bootboot-start-markerboot system flash:c2800nm-advsecurityk9-mz.12.4-15.T3.binboot-end-marker<\/em><\/strong><\/pre>\n\n\n\n<p>b. remove the old boot statement&nbsp; (Output in step a)<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>config tno boot system flash:c2800nm-advsecurityk9-mz.12.4-15.T3.bin<\/em><\/strong><\/pre>\n\n\n\n<p>c. add the new boot statement&nbsp; (this will include the file name of the new binary)<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>boot system flash:c2800nm-advsecurityk9-mz.15.0-1-M8.bin<\/em><\/strong><\/pre>\n\n\n\n<p><strong>Step 4: Save configuration changes<\/strong><\/p>\n\n\n\n<p>While still in configuration mode from before:<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>endwrite memoryshow start | include bootboot-start-markerboot system flash:c2800nm-advsecurityk9-mz.15.0-1-M8.binboot-end-marker<\/em><\/strong><\/pre>\n\n\n\n<p>To recap all of the commands (in this example) would then be:<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><strong><em>show run | include bootconfig tno boot system flash:c2800nm-advsecurityk9-mz.12.4-15.T3.binboot system flash:c2800nm-advsecurityk9-mz.15.0-1-M8.binendwrite memoryshow start | include boot<\/em><\/strong><\/pre>\n\n\n\n<p><strong>Step 5: Reload the device and verify that the correct IOS has loaded<\/strong><\/p>\n\n\n\n<p>For normal ISR&#8217;s the only way to change the IOS is to reload the device.&nbsp; (ISSU, In-Service Software Upgrade, is not currently supported.)<\/p>\n\n\n\n<p>After the device has reloaded please do a &#8220;show version&#8221; and confirm that the router is now running the correct version of IOS.&nbsp;<\/p>\n\n\n\n<p>Then you are done.<\/p>\n","protected":false},"excerpt":{"rendered":"<p><span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading Time-approximately:<\/span> <span class=\"rt-time\"> 2<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span>You can use these steps to either upgrade or downgrade the IOS on an ISR router. We have used the Cisco 2800 Series Integrated Services Router (ISR) in this example. By Tekmart Africa Enterprise Support First up, you must make sure you have done the following ready : 1) Get the new IOS to the router 2) Verify the integrity<\/p>\n<p><a class=\"more-link\" href=\"https:\/\/tekmart.co.za\/t-blog\/upgrading-or-downgrading-the-ios-on-an-isr-or-similar-router-a-simple-how-to-step-by-step-guide\/\">Read More<\/a><\/p>\n","protected":false},"author":113,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,207,302,36,4,30,16,3,103,12,196],"tags":[],"class_list":["post-8348","post","type-post","status-publish","format-standard","hentry","category-data-center-hardware","category-data-center-networking","category-data-center-storage-and-networking","category-data-center-systems-management","category-datacenter-news","category-expert-advise-and-opinion","category-how-tos-and-other-useful-tips-and-tricks","category-industry-news-and-expert-advise","category-research-results-and-trends","category-tekmart-enterprise-hardware-tips","category-tekmart-support-storage-systems-implementation-tutorials"],"_links":{"self":[{"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/posts\/8348","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/users\/113"}],"replies":[{"embeddable":true,"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/comments?post=8348"}],"version-history":[{"count":7,"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/posts\/8348\/revisions"}],"predecessor-version":[{"id":8358,"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/posts\/8348\/revisions\/8358"}],"wp:attachment":[{"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/media?parent=8348"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/categories?post=8348"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tekmart.co.za\/t-blog\/wp-json\/wp\/v2\/tags?post=8348"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}