If you are connecting to the Internet via a dialup connection, a configuration file is necessary for the interface.
PPP interface files are named using the following format:
ifcfg-pppX
where X
is a unique number corresponding to a specific interface.
The PPP interface configuration file is created automatically when wvdial
, the Network Administration Tool or Kppp is used to create a dialup account. It is also possible to create and edit this file manually.
The following is a typical ifcfg-ppp0
file:
DEVICE=ppp0
NAME=test
WVDIALSECT=test
MODEMPORT=/dev/modem
LINESPEED=115200
PAPNAME=test
USERCTL=true
ONBOOT=no
PERSIST=no
DEFROUTE=yes
PEERDNS=yes
DEMAND=no
IDLETIMEOUT=600
Serial Line Internet Protocol (
SLIP) is another dialup interface, although it is used less frequently. SLIP files have interface configuration file names such as
ifcfg-sl0
.
Other options that may be used in these files include:
-
DEFROUTE
=answer
where answer
is one of the following:
DEMAND
=answer
where answer
is one of the following:
IDLETIMEOUT
=value
where value
is the number of seconds of idle activity before the interface disconnects itself.
INITSTRING
=string
where string
is the initialization string passed to the modem device. This option is primarily used in conjunction with SLIP interfaces.
LINESPEED
=value
where value
is the baud rate of the device. Possible standard values include 57600
, 38400
, 19200
, and 9600
.
MODEMPORT
=device
where device
is the name of the serial device that is used to establish the connection for the interface.
MTU
=value
where
value
is the
Maximum Transfer Unit (
MTU) setting for the interface. The MTU refers to the largest number of bytes of data a frame can carry, not counting its header information. In some dialup situations, setting this to a value of
576
results in fewer packets dropped and a slight improvement to the throughput for a connection.
NAME
=name
where name
is the reference to the title given to a collection of dialup connection configurations.
PAPNAME
=name
where
name
is the username given during the
Password Authentication Protocol (
PAP) exchange that occurs to allow connections to a remote system.
PERSIST
=answer
where answer
is one of the following:
yes
— This interface should be kept active at all times, even if deactivated after a modem hang up.
no
— This interface should not be kept active at all times.
REMIP
=address
where address
is the IP address of the remote system. This is usually left unspecified.
-
WVDIALSECT
=name
where name
associates this interface with a dialer configuration in /etc/wvdial.conf
. This file contains the phone number to be dialed and other important information for the interface.