7.5 Perform device maintenance

7.5 Perform device maintenance

  • 7.5.a Cisco IOS upgrades and recovery (SCP, FTP, TFTP, and MD5 verify)

To use MD5 to verify an image:

R1#verify /md5 flash0:<imagename> <md5sum>

To send an image via SCP (secure copy over SSH):

Run this command from your Linux/BSD machine:

desktop$ scp <imagename> <username>@<host>:flash0:<imagename>

To copy via FTP/TFTP:

R1#: copy ftp://username:pass@<host>/path flash

R1#: copy ftpt://<host>/path flash
  • 7.5.b Password recovery and configuration register


1.) Remove power

2.) Remove flash memory

3.) Turn on router

4.) Configure ROMMON

rommon 1> 0x2142

5.) Turn off router

6.) Restore flash and power

7.) Router will boot with no config:

Router> enable

Router#copy startup-config running-config

R1#configure terminal

R1(config)#enable secret password

R1(config)#config-reg 0x2102


8.) copy new password to startup-config

R1# copy running-config startup-config


  • 7.5.c File system management


To copy files to a USB drive:

R1# copy running-config usbflash1:copy-of-run-config

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