Hi - so you want to wipe the JUNOS configuration and start again? One option I thought about was to go into configuration mode and delete everything:
root@cpe0-mx5# delete
This will delete the entire configuration
Delete everything under this level? [yes,no] (no) yes

But when I tried to commit that change I got told...no way

[edit]
root@cpe0-mx5# commit
error: cannot commit an empty configuration

So I tried to load the factory default configuration:

root@cpe0-mx5# load factory-default ?
Possible completions:
  <[Enter]>            Execute this command
  |                    Pipe through a command
[edit]
root@cpe0-mx5# load factory-default   
warning: activating factory configuration

But then again I was told that I needed to sat the root authentication password etc.

root@cpe0-mx5# commit
[edit]
  'system'
    Missing mandatory statement: 'root-authentication'
error: commit failed: (missing statements)

[edit]

So it's not quite a factory default config because I now need to set the root password! Bad news is you can't even choose a basic password like 'password' or toor or root because it has a minimum digits of 6 and requires a change of case and punctuation plus numbers!

Damn - hosed.

so how do you REALLY remove all the configuration? Well it turns out you have to go into the underlying filesystem and use the BSD binaries. so first of all come out of configuration mode. It'll ask you if you want to leave without commiting the changes - you can say yes


So now lets start the CLI for BSD.



Go to the config directory using the 'cd' (Change Directory) command

root@cpe0-mx5% cd /config


Here is a listing of the files in there before we delete them.



So now lets delete (remove - rm) the config files. It'll maybe error about one file because we don't have the rights to delete it...thats a good thing.



Now lets take a look...files gone?

root@cpe0-mx5% ls
.snap           usage.db

OK we're good lets do a reboot and hopefully it'll be a vanilla config now.

root@cpe0-mx5% reboot

So when the router comes back we're looking to see if it has forgotten everything and become an Amnesiac?

----output truncated-----
root@%

Job Done!