System Administration Guide: Network Services

/etc/ppp/chap-secrets File

The CHAP database is implemented in the /etc/ppp/chap-secrets file. Machines on both sides of the PPP link must have each others' CHAP credentials in their /etc/ppp/chap-secrets files for successful authentication.


Note –

Unlike PAP, the shared secret must be in the clear on both peers. You cannot use crypt, PAM, or the PPP login option with CHAP.


The /etc/ppp/chap-secrets file has the following syntax.


myclient myserver secret5748 *

The parameters have the following meanings:

myclient

CHAP user name of the caller. This name can be the same as or different from the caller's UNIX user name.

myserver

Name of the remote machine, often a dial-in server.

secret5748

Caller's CHAP secret.


Note –

Unlike PAP passwords, CHAP secrets are never sent over the link. Rather, CHAP secrets are used when the local machines compute the response.


*

IP address that is associated with the caller. Use an asterisk (*) to indicate any IP address.