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<P>when a PPP client connects to the ppp0 interface, it is automatically given the name srv-ss2 along with the IP address of srv-ss2.
</P>
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<TR><TD><FONT SIZE="+1"><B>Multiple modem</B></FONT>
<BR>If a Linux system has more than one modem connected to it, each modem on which users can dial up should have a separate file <TT>/etc/ppp/options.tty<I>XX</I></TT>, where <TT><I>XX</I></TT> corresponds to the modem’s number (starting with 01).</TABLE>
<H4 ALIGN="LEFT"><A NAME="Heading17"></A><FONT COLOR="#000077">Configuring Getty Devices</FONT></H4>
<P>When a user dials into a Linux system, three actions must be performed before the user can log on:
</P>
<DL>
<DD><B>1.</B> Open tty lines and set their modes.
<DD><B>2.</B> Print the logon prompt.
<DD><B>3.</B> Initiate the logon process for the user.
</DL>
<P>These actions are handled by the <TT>getty</TT> program, which keeps a list of tty lines and their modes and sets the mode of dial-up connection to the appropriate entry in the list. Each individual entry in the list is referred to as a <TT>getty</TT> device. After the line has been set up, <TT>getty</TT> prints the logon prompt and initiates the logon process.</P>
<P>The process of configuring <TT>getty</TT> devices is done by adding entries to the <TT>/etc/gettydefs file</TT>. The default version of this file is fine for most installations, but occasionally, entries for newer or faster modem types must be added.</P>
<P>A sample entry in the <TT>/etc/gettydefs</TT> files looks like this:</P>
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<PRE>
# 19200 fixed-baud modem entry
F19200# B19200 CS8 # B19200 SANE -ISTRIP HUPCL #@S login:
#F19200
</PRE>
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<P><B><TT>gettydefs</TT> file format"</B><BR>The <TT>/etc/gettydefs</TT> file has the same convention as most UNIX configuration files, in that lines starting with the # character or completely blank lines are ignored. All other lines are treated as configuration entries.</P>
<P>Usually a configuration entry consists of two lines. The first line is a description of the entry, and the second is the entry itself. Strictly speaking, only the configuration lines are required, but it is a good idea to include a description for each entry.</P>
<P>Entries are made up of five values separated by the # character.</TABLE>
</P>
<P>The first and the last value in each entry describe the speed of the modem. These must always be the same. In this case, we see that the speed is 19200, which corresponds to a 19.2Kb modem.</P>
<P>The second and third values are called the init flags and the final flags. These are given in this format:</P>
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<PRE>
B[speed] [options]
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<P>Because the speed for this entry is 19200, the init flags are set as <TT>B19200 CS8</TT> and the final flags are set as <TT>B19200 SANE -ISTRIP HUPCL</TT>. Usually the only option specified for init flags is <TT>CS8</TT>. The options that can be specified for the final flags are covered in great detail in the <TT>getty man</TT> page, but the most common options used are the ones listed in this entry.</P>
<P>The fourth entry is the prompt to be issued for the user to log on. This can be set to any value, but the standard is either <TT>login:</TT> or <TT>username:</TT>.</P><P><BR></P>
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