{"id":874,"date":"2014-02-06T17:00:42","date_gmt":"2014-02-06T17:00:42","guid":{"rendered":"http:\/\/www.balajibandi.com\/?p=874"},"modified":"2019-05-06T17:17:17","modified_gmt":"2019-05-06T16:17:17","slug":"how-to-recover-a-cisco-switch-from-boot-loader-3560-3750","status":"publish","type":"post","link":"https:\/\/www.balajibandi.com\/?p=874","title":{"rendered":"How-To Recover a Cisco Switch from Boot Loader 3560\/3750"},"content":{"rendered":"\n

Recovering from a Software Failure<\/h2>\n\n\n\n

Method 1: Transferring IOS image using TFTP<\/strong><\/h2>\n\n\n\n

\nSwitch software can be corrupted during an \nupgrade, by downloading the wrong file to the switch, and by deleting \nthe image file. In all of these cases, the switch does not pass the \npower-on self-test (POST), and there is no connectivity.<\/p>\n\n\n\n

\nThis procedure uses boot loader commands and TFTP to recover from a corrupted or wrong image file.<\/p>\n\n\n\n

This recovery procedure requires that you have physical access to the switch.<\/p>\n\n\n\n

You need 2 Cables – 1. Console Cable and 1 Ethernet Cable<\/p>\n\n\n\n

Step 1:<\/strong> Console into the Switch.<\/p>\n\n\n\n

Step 2:<\/strong> Connect your Labtop\/PC (or TFTP Server<\/a>) to the back port of the Switch (10\/100TX, next to console\/serial port) via Straight cable..<\/em><\/p>\n\n\n\n

Power on the Switch<\/p>\n\n\n\n

Step 3:<\/strong> Initialize flash:<\/p>\n\n\n\n

switch: flash_init<\/pre>\n\n\n\n
Step4:<\/strong> Initialize Management Interface<\/p>\n\n\n\n
switch: mgmt_init<\/pre>\n\n\n\n
Step5:<\/strong> Assign IP address\/Subnet Mask of the Management Interface<\/strong> (Not TFTP Server<\/strong>,\n which is mentioned in the Cisco documentation and is an error.) and \ndefault gateway. Make sure the variable are set in the same format \nbelow.<\/p>\n\n\n\n
Example:  
switch: set IP_ADDR 192.168.1.2\/255.255.255.0 
switch: set DEFAULT_ROUTER 192.168.1.1

Note : My PC IP address 192.168.1.1 ( which is connected to one of the Switch Port)

 
Step6:<\/strong> Once the correct image placed in TFTP Folder, To Transfer the image to Switch from Laptop\/TFTP server you can enter: 

Example:  
switch: copy tftp:\/\/192.168.1.1\/ 
c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong> flash:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong> <\/pre>\n\n\n\n
After completion of Transfer you see  successfully copied to “flash:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong>“<\/p>\n\n\n\n
 Step 7: Boot up the newly downloaded Cisco IOS image. <\/p>\n\n\n\n
switch: boot flash:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong><\/p>\n\n\n\n
Once boot success setup boot variable :<\/p>\n\n\n\n
Step 8 :
switch: set BOOT flash:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong> 

Save and reload and test.<\/pre>\n\n\n\n
Method 2: Transferring IOS image using USB Flash drive.<\/strong><\/h2>\n\n\n\n
Before creating this post I didn\u2019t know the Boot Loader (Rommon) mode  supports USB flash drive -The steps as as  below.<\/p>\n\n\n\n
Step 1:<\/strong>\u00a0Take a USB of any size, format it using FAT16<\/strong>.<\/p>\n\n\n\n
Step 2:<\/strong> Copy a valid IOS to the USB drive.<\/p>\n\n\n\n
Step 3:<\/strong> Insert USB to your Router\/Switch.<\/p>\n\n\n\n
Step 4:<\/strong> Reset you Router\/Switch.<\/p>\n\n\n\n
Step 5:<\/strong> Enter following comman<\/p>\n\n\n\n
switch: dir usbflash0:<\/pre>\n\n\n\n
Step 6:<\/strong> Once you verify that it has detected the flash you can boot router\/Switch using the following command<\/p>\n\n\n\n
switch: boot usbflash0:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong> 

Step 7: Boot up the newly downloaded Cisco IOS image. 
 switch: boot flash:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong>
 
 Once boot success setup boot variable :
 
 Step 8 :
switch: set BOOT flash:c3560e-ipbasek9-mz.122-55.SE12.bin<\/strong> 

Save and reload and test. <\/pre>\n","protected":false},"excerpt":{"rendered":"
Recovering from a Software Failure Method 1: Transferring IOS image using TFTP Switch software can be corrupted during an upgrade, by downloading the wrong file to the switch, and by deleting the image file. In all of these cases, the switch does not pass the power-on self-test (POST), and there is no connectivity. This procedure […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10,2],"tags":[],"class_list":["post-874","post","type-post","status-publish","format-standard","hentry","category-ccie-rns","category-cisco"],"_links":{"self":[{"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=\/wp\/v2\/posts\/874","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=874"}],"version-history":[{"count":1,"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=\/wp\/v2\/posts\/874\/revisions"}],"predecessor-version":[{"id":875,"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=\/wp\/v2\/posts\/874\/revisions\/875"}],"wp:attachment":[{"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=874"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=874"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.balajibandi.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=874"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}