Where to Find Sample /etc/ppp/peers/peer-name Files

Table 36-4 Examples of /etc/ppp/peers/peer-name Files

Configuring Modems for a Dial-up Link

This section contains information about configuring modems.

Configuring the Modem Speed

A major issue in modem configuration is designating the speed at which the modem should operate. The following guidelines apply to modems that are used with Sun Microsystems computers:

• Older SPARC systems - Check the hardware documentation that accompanies the system. Many SPARCstation™ machines require modem speed not to exceed 38400 bps.

• UltraSPARC™ machines - Set the modem speed to 115200 bps, which is useful with modern modems and fast enough for a dial-up link. If you plan to use a dual-channel ISDN TA with compression, you need to increase the modem speed. The limit on an UltraSPARC is 460800 bps for an asynchronous link.

For a dial-out machine, set the modem speed in the PPP configuration files, such as /etc/ppp/peers/peer-name, or by specifying the speed as an option for pppd.

For a dial-in server, you need to set the speed by using the ttymon facility or admintool, as described in "Configuring Devices on the Dial-in Server".

Defining the Conversation on the Dial-up Link

The dial-out machine and its remote peer communicate across the PPP link by negotiating and exchanging various instructions. When configuring a dial-out machine, you need to determine what instructions are required by the local and remote modems. Then you create a file that is called a chat script that contains these instructions. This section discusses information about configuring modems and creating chat scripts.

Contents of the Chat Script

Each remote peer that the dial-out machine needs to connect to probably requires its own chat script.

Note - Chat scripts are typically used only on dial-up links. Leased-line links do not use chat scripts unless an asynchronous interface is used that requires startup configuration.

The contents of the chat script are determined by the requirements of your modem model or ISDN TA, and the remote peer. These contents appear as a set of expect-send strings that the dial-out machine and its remote peers exchange as part of the communications initiation process.

An expect string contains characters that the dial-out host machine expects to receive from the remote peer to initiate conversation. A send string contains characters that the dial-out machine sends to the remote peer after receiving the expect string.

Information in the chat script usually includes the following:

• Modem commands (often referred to as AT commands), which enable the modem to transmit data over the telephone

• Phone number of the target peer

  This phone number might be the number that is required by your ISP, or a dial-in server at a corporate site, or an individual machine.

• Time-out value, if required

• Login sequence that is expected from the remote peer

• Login sequence that is sent by the dial-out machine

Chat Script Examples

This section contains chat scripts that you can use as a reference for creating your own chat scripts. The modem manufacturer's guide and information from your ISP and other target hosts contain chat requirements for the modem and your target peers. In addition, numerous PPP web sites have sample chat scripts.

Basic Modem Chat Script

The following is a basic chat script that you can use as a template for creating your own chat scripts.

ABORT BUSY ABORT 'NO CARRIER' REPORT CONNECT TIMEOUT 10 "" AT&F1M0&M5S2=255 SAY "Calling myserver\n" TIMEOUT 60 OK "ATDT1-123-555-1212" ogin: pppuser ssword: \q\U % pppd

The next table describes the contents of the chat script.

/etc/ppp/myisp-chat.tmpl Chat Script Template

Solaris PPP 4.0 includes the /etc/ppp/myisp-chat.tmpl, which you can modify for use at your site. /etc/ppp/myisp-chat.tmpl is similar to the basic modem chat script except that it does not include a login sequence.

ABORT   BUSY
ABORT   'NO CARRIER'
REPORT  CONNECT
TIMEOUT 10
""      "AT&F1"
OK      "AT&C1&D2"
SAY     "Calling myisp\n"
TIMEOUT 60
OK      "ATDT1-123-555-1212"
CONNECT \c