I have a Cisco router, and I want to remove a few lines from startup-config. How could I do it? Do I need to copy it over to a PC, edit it there, then copy it back, or can I do it through the serial console somehow?
Cisco Startup-Config – Editing Startup-Config on Cisco Devices
ciscocisco-ios
Best Answer
Edit: Karl Billington's method is superior and should be used when possible
The other (extremely painful) way is:
Setup a console connection if you don't already have one. The rest of the steps below are over the console connection
Reboot the switch, stop it at the rommon/bootloader (usually Control-C or break)
Configure the rommon/bootloader to ignore the startup Boot the IOS. It should come up with a default config after ignoring the startup-config
Run
show startup-config
. This will print the entire startup-config, including the undesirable lines that you want to remove.Now do a
conf term
and start pasting the output ofshow startup-config
, excluding the undesirable lines that you want to excludeIssue the command
wr mem
. This will save your edited config.Reboot. This time configure the rommon/bootloader to not ignore the startup-config
As you can see this is extremely messy, and is error-prone especially if your config is large. But if the real solution (editing it off-box and then copying it to the device) won't work for whatever reason, and you're in a "desperate times call for desperate measures" situation, you can give this a shot.