Configure PPP dial-in mode for a serial port

The serial port is enabled by default. To disable, toggle off Enable.

(Optional) For Label, enter a label that will be used when referring to this port.

For Baud rate, select the baud rate used by the device to which you want to connect. The default is 9600.

For Flow control, select the type of flow control used by the device to which you want to connect. The default is None.

For Idle timeout, type the amount of time that the active session can be idle before the session is disconnected.

Allowed values are any number of weeks, days, hours, minutes, or seconds, and take the format number{w|d|h|m|s}.

For example, to set Idle timeout to ten minutes, enter 10m or 600s.

Click to expand PPP dial-in.

For Local IP address, type the IP address assigned to this interface.

For Remote IP address, type the IP address assigned to the remote peer.

For Metric, set the priority of routes associated with this interface. If there are multiple active routes that match a destination, then the route with the lowest metric will be used.

For Default route, toggle to control whether a default route gets added for the PPP interface. This feature is disabled by default.

For Zone, select the firewall zone for this interface. This can be used by packet filtering rules and access control lists to restrict network traffic on this interface.

For Authentication method, select the method used to authenticate the remote peer. Allowed values are:

• None: No authentication is required.

• Automatic: Attempt to authenticate using CHAP first, and then PAP.

• CHAP: Use Challenge Handshake Authentication Protocol (CHAP) to authenticate.

• PAP: Use Password Authentication Protocol (PAP) to authenticate.

If Automatic, CHAP, or PAP are selected, type the Username and Password used to authenticate the remote peer.

(Optional) Configure the serial port to use a custom PPP configuration file:

1. Click to expand Custom PPP configuration.

2. Click Enable to enable the use of a custom PPP configuration file.

3. Click Override to override the default PPP configuration and only use the custom configuration file.

   If Override is not enabled, the custom PPP configuration file is used in addition to the default configuration.

4. For Configuration file, paste or type the configuration data in the format of a pppd options file. Because the options are passed directly to the pppd command line, they should all be entered on a single line. For example:

   debug lcp-echo-interval 10 lcp-echo-failure 2

(Optional) Configure a script that will be run to prepare the link before PPP negotiations are started:

1. Click to expand Connect script.

2. Click Enable to enable the use of a connection script.

3. For Connect script filename, type the name of the script. Scripts are located in the /etc/config/serial directory. An example script, windows_dun.sh is provided.

   Example windows_dun.sh file:

   #!/bin/sh
   
   # Example connect script for connecting from a PC using a Windows dial-up
   # networking connection with built-in standard 33600 bps modem driver and phone
   # number 123.
   
   # The shell's 'read' builtin breaks on newline, so translate incoming carriage-
   # return to newline, and outgoing newline to carriage-return-newline.
   stty icrnl onlcr opost
   
   # Read input from the serial port, one line at a time.
   while read -r line; do
       case "$line" in
           ATDT123)
               echo "CONNECT" # instruct the peer to start PPP
               exit 0 # start up the local PPP session
               ;;
           AT*)
               echo "OK" # passively accept any other AT command
               ;;
       esac
   done

Depending on your device configuration, you may be presented with an Access selection menu. Type admin to access the Admin CLI.

> config
(config)>

(config)> serial port1 enable false
(config)>

(config)> serial port1 mode ppp_dialin
(config)>

(config)> serial port1  label label
(config)>

(config)> serial port1 baudrate rate
(config)>

(config)> serial port1 flow value
(config)>

where value is one of:

• none

• rts/cts

• xon/xoff

Set the amount of time that the active session can be idle before the session is disconnected:

(config)> serial port1 idle_timeout value
(config)>

where value is any number of weeks, days, hours, minutes, or seconds, and takes the format number{w|d|h|m|s}.

For example, to set idle_timeout to ten minutes, enter either 10m or 600s:

(config)> serial port1 idle_timeout 600s
(config)> 

(config)> serial port1 ppp_dialin local_address IPv4_address
(config)>

(config)> serial port1 ppp_dialin remote_address IPv4_address
(config)>

(config)> serial port1 ppp_dialin default_route true
config)>

Set the authentication method used to authenticate the remote peer:

(config)> serial port1 ppp_dialin auth value
(config)>

where value is one of:

• none: No authentication is required.

• auto: Attempt to authenticate using CHAP first, and then PAP.

• chap: Use Challenge Handshake Authentication Protocol (CHAP) to authenticate.

• pap: Use Password Authentication Protocol (PAP) to authenticate.

The default is none.

If auto, chap, or pap are set, set the username and password used to authenticate the remote peer:

(config)> serial port1 ppp_dialin username username
(config)> serial port1 ppp_dialin password password
(config)>

Set the priority of routes associated with this interface. If there are multiple active routes that match a destination, then the route with the lowest metric will be used.

(config)> serial port1 ppp_dialin metric int
(config)>

The default is 10.

Set the firewall zone for this interface. This can be used by packet filtering rules and access control lists to restrict network traffic on this interface.

1. Use the ? to determine available zones:

   (config)> serial port1 ppp_dialin zone ?
   
   Zone: The firewall zone assigned to this interface. This can be used by packet
   filtering rules and access control lists to restrict network traffic on this
   interface.
   Format:
     any
     dynamic_routes
     edge
     external
     internal
     ipsec
     loopback
     setup
   Default value: internal
   Current value: internal
   
   (config)> 

2. Set the zone:

   (config)> serial port1 ppp_dialin zone zone
   (config)> 

(Optional) Configure the serial port to use a custom PPP configuration file:

1. Enable the use of a custom PPP configuration file:

   (config)> serial port1 ppp_dialin custom enable true
   (config)> 

2. Enable override to override the default PPP configuration and only use the custom configuration file:

   (config)> serial port1 ppp_dialin custom override true
   (config)> 

   If override is not enabled, the custom PPP configuration file is used in addition to the default configuration.

3. Paste or type the configuration data in the format of a pppd options file:

   (config)> serial port1 ppp_dialin custom config_file data
   (config)> 

   where data are one or more pppd command line options. Because the options are passed directly to the pppd command line, they should all be entered on a single line. For example:

   (config)> serial port1 ppp_dialin custom config_file "debug lcp-echo-interval 10 lcp-echo-failure 2"
   (config)> 

(Optional) Configure a script that will be run to prepare the link before PPP negotiations are started:

1. Enable the use of a connection script.

   (config)> serial port1 ppp_dialin connect enable true
   (config)> 

2. Set the name of the script:

   (config)> serial port1 ppp_dialin connect script filename
   (config)> 

   Scripts are located in the /etc/config/serial directory. An example script, windows_dun.sh is provided.

   Example windows_dun.sh file:

   #!/bin/sh
   
   # Example connect script for connecting from a PC using a Windows dial-up
   # networking connection with built-in standard 33600 bps modem driver and phone
   # number 123.
   
   # The shell's 'read' builtin breaks on newline, so translate incoming carriage-
   # return to newline, and outgoing newline to carriage-return-newline.
   stty icrnl onlcr opost
   
   # Read input from the serial port, one line at a time.
   while read -r line; do
       case "$line" in
           ATDT123)
               echo "CONNECT" # instruct the peer to start PPP
               exit 0 # start up the local PPP session
               ;;
           AT*)
               echo "OK" # passively accept any other AT command
               ;;
       esac
   done

(config)> save
Configuration saved.
>

Depending on your device configuration, you may be presented with an Access selection menu. Type quit to disconnect from the device.