None of the LEAF variants has a userid pre-defined for use with PPP. I prefer to add such a dedicated userid, because doing so makes it unnecessary to give dial-in PPP users shell access to the router itself. Instead, you can provide dial-in users with access to the LAN and/or the Internet, but keep the router itself invisible to the dial-up PPP user, hence more secure.

Creating the user is tricky due to the inherent lack of the 'useradd' command in the LEAF variants. Lack of this utility mandates that you create the user by hand. I am using the example user 'ppp' in this configuration, however this will need to be modified for the username that is desired to be logged in with over the dial-in connection. The process of creating the user by hand is as follows:

Add this line to the '/etc/passwd' file:

ppp:x:101:101:ppp:/home/ppp:/usr/sbin/pppd

Add this line to the '/etc/shadow' file:

ppp:*:10091:0:99999:7:::

If you would like to set the password for this user, use the command:

passwd ppp

The method of using 'pppd' for the login shell directly starts the connection automatically and does not give shell access to the user.