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<UL>

	<LI><A HREF="#Heading1">- 44 -</A>

	<UL>

		<LI><A HREF="#Heading2">UUCP</A>

		<UL>

			<LI><A HREF="#Heading3">UUCP Configuration</A>

			<UL>

				<LI><A HREF="#Heading4">Taylor UUCP Configuration</A>

			</UL>

			<LI><A HREF="#Heading5">NOTE</A>

			<LI><A HREF="#Heading6">NOTE</A>

			<UL>

				<LI><A HREF="#Heading7">HDB UUCP Configuration</A>

			</UL>

			<LI><A HREF="#Heading8">A UUCP Connection</A>

			<LI><A HREF="#Heading9">Direct Connections</A>

			<LI><A HREF="#Heading10">Login Scripts</A>

			<LI><A HREF="#Heading11">Changing Access Times</A>

			<LI><A HREF="#Heading12">UUCP Security</A>

			<LI><A HREF="#Heading13">Using UUCP</A>

			<LI><A HREF="#Heading14">NOTE</A>

			<LI><A HREF="#Heading15">CAUTION</A>

			<UL>

				<LI><A HREF="#Heading16">Sending E-Mail with UUCP</A>

				<LI><A HREF="#Heading17">Transferring Files with UUCP</A>

				<LI><A HREF="#Heading18">Checking on Transfers</A>

			</UL>

			<LI><A HREF="#Heading19">Summary</A>

		</UL>

	</UL>

</UL>



<P>

<HR SIZE="4">



<H2 ALIGN="CENTER"><A NAME="Heading1<FONT COLOR="#000077">- 44 -</FONT></H2>

<H2 ALIGN="CENTER"><A NAME="Heading2<FONT COLOR="#000077">UUCP</FONT></H2>

<P><I>by Tim Parker</I></P>

<P>IN THIS CHAPTER</P>



<UL>

	<LI>UUCP Configuration 

	<P>

	<LI>A UUCP Connection 

	<P>

	<LI>Direct Connections 

	<P>

	<LI>Login Scripts 

	<P>

	<LI>Changing Access Times 

	<P>

	<LI>UUCP Security 

	<P>

	<LI>Using UUCP 

</UL>



<P>UUCP (UNIX to UNIX CoPy) was developed to provide a simple dial-up networking

protocol for UNIX systems. It is most often used today as an e-mail transfer system,

allowing non-networked machines to transfer e-mail easily over a modem connection.

It can also be used for Usenet news and access to similar services that do not require

a dedicated connection. UUCP is a two-machine connection, between your Linux machine

and another machine running UUCP. UUCP cannot be used as a remote system access system

(like FTP or Telnet), nor can it be used as a standard login because the protocols

do not support this type of interactive behavior. UUCP does have security features

that are adequate for most purposes, but UUCP is the primary source of break-ins

for many systems because most system administrators don't bother to set the security

system up properly.</P>



<P>Linux can run any of several different versions of UUCP, most of which are compatible

with each other to a reasonable extent, except when it comes to configuration and

installation procedures. Many Linux versions offer you a choice between the Taylor

UUCP version and the HDB (HoneyDanBer) UUCP. You can use whichever single version

came with your Linux software, or if you have both, you can choose between the two

(or use both versions as the mood strikes you). Many Linux users prefer the Taylor

UUCP implementation, while users who have worked on other UNIX systems prefer HDB

because it is more recent. We'll look at both versions in this chapter. (There are

even more UUCP versions, but we will ignore them because they are seldom used under

Linux.) The first part of the chapter deals with configuring UUCP, while the rest

covers using it.

<H3 ALIGN="CENTER"><A NAME="Heading3<FONT COLOR="#000077">UUCP Configuration</FONT></H3>

<P>Most of the configuration required for UUCP takes place under the <TT>/usr/lib/uucp</TT>

directory. There are several files used by UUCP, most of which need direct administrator

modification to set up properly. While the configuration process can seem awfully

complex to someone who has never done it before, there are really only a few files

that need changing, and only one or two entries in each file.</P>

<P>The configuration process for Taylor UUCP and HDB UUCP are completely different,

so we will look at them separately. However, you don't have to worry which version

of UUCP is being run at the remote end of the connection because both can talk to

each other (at least that's usually the case), as long as the configuration files

are set up properly.</P>

<P>Some versions of Linux have semiautomated UUCP configuration scripts. These are

more common with HDB UUCP than Taylor UUCP, but a few helpful scripts are also available

for the latter. If you have one of these scripts, by all means use it, but do check

the files manually afterwards.</P>

<P>For the configuration processes discussed in the following section, we will assume

that our host machine's name is <TT>merlin</TT>, and we want to connect via UUCP

to another Linux system called <TT>arthur</TT>. As you go through the process, take

care to enter the information in the same format as the examples, but don't mix Taylor

and HDB UUCP information.

<H4 ALIGN="CENTER"><A NAME="Heading4<FONT COLOR="#000077">Taylor UUCP Configuration</FONT></H4>

<P>We can begin with a quick look at the configuration files involved in the Taylor

UUCP system. These are the filenames and their primary purposes:



<UL>

	<LI><TT>/usr/lib/uucp/config</TT>--Defines the local machine name.

	<P>

	<LI><TT>/usr/lib/uucp/sys</TT>--Defines the remote systems and how to call them.

	<P>

	<LI><TT>/usr/lib/uucp/port</TT>--Describes each port for calling out and its parameters.

	<P>

	<LI><TT>/usr/lib/uucp/dial</TT>--Describes the dialers for calling out.

	<P>

	<LI><TT>/usr/lib/uucp/dialcodes</TT>--Used to contain expansions for symbolic dialcodes,

	but is rarely used when a straight-out telephone connection exists.

	<P>

	<LI><TT>/usr/lib/uucp/call</TT>--Can contain the login name and password for remote

	systems, but it is rarely used now.

	<P>

	<LI><TT>/usr/lib/uucp/passwd</TT>--Contains the login names and passwords used when

	remote systems connect to your local machine. Used only when <TT>uucico</TT> is password

	checking instead of using the login process.

</UL>



<P>To make the configuration process easier, we will ignore all the theory and background

information and proceed with a sample configuration. You need only modify the entries

to suit your own names, telephone numbers, device files, and so on, and the configuration

process will be the same. It can then be repeated for as many systems as you want

to connect to.</P>

<P>The first file to modify holds your system name and other general parameters.

The file <TT>/usr/lib/uucp/config</TT> needs a single-line entry for your system

name such as this one:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">nodename     merlin

</FONT></PRE>

<P>The keyword <TT>nodename</TT> must be first on the line followed by whitespace

(spaces or tabs), then your machine name. The information in this file may have been

completed when you installed Linux, but you should manually check the contents to

make sure. If your system's name isn't set correctly, the connection to the remote

system won't work properly.



<DL>

	<DT></DT>

</DL>





<DL>

	<DD>

<HR>

<A NAME="Heading5<FONT COLOR="#000077"><B>NOTE: </B></FONT>To use UUCP, you

	must have a system name. For compatibility with most versions of UUCP, keep the name

	to seven characters or less. Ideally, the UUCP name is the same name you assigned

	to your host during configuration. The name doesn't have to follow a convention (such

	as the system name used by TCP/IP for Internet access), but if you use other network

	protocols, keep a consistent name. If you have a domain name (for TCP/IP access)

	use the first component of the machine's full TCP/IP name as the UUCP name. For example,

	if your full domain name is <TT>merlin.wizards.com</TT>, use the UUCP name <TT>merlin</TT>.

<HR>



</DL>



<P>You also need information about the remote system you want to connect to. The

<TT>/usr/lib/uucp/sys</TT> file holds all the information about remote systems. This

file usually has a few sample entries in it, which you can copy or modify. Make sure

you don't leave comment marks (pound or hash marks) in the first column or the entries

will be ignored. A <TT>/usr/lib/uucp/sys</TT> entry for the remote machine <TT>merlin</TT>

looks like this:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF"># system: arthur (Bill Smallwood's Linux system)

system    arthur

time     Any

phone     [phone]

port     com1

speed      9600

chat     login: merlin password: secret1

</FONT></PRE>

<P>The first line in the preceding extract is a comment line. Most system administrators

like to put a comment line in to identify each system. The next lines identify the

different aspects of the remote system, including its name (<TT>arthur</TT>), times

at which it can be called (<TT>Any</TT> in this case, meaning no restrictions), the

telephone number (including any area code or special digits that have to be dialed),

the serial port to be used for the connection (in this case, <TT>com1</TT>), the

speed at which to connect (9600 baud), and the chat script or login process. In this

case, the chat script tells UUCP to wait until it sees the string <TT>login:</TT>

then to send <TT>merlin</TT>, then wait for the prompt <TT>password:</TT> and then

to send <TT>secret1</TT>.</P>

<P>Most login scripts will require a login and password, and they must be placed

in the configuration file because UUCP doesn't allow interactive sessions. This can

be a bit of a problem because it allows other users on your system to see the login

password for the remote machine, but since it can be used only by UUCP, this is not

a major concern. Also, the file permissions on the UUCP configuration files can be

set to prevent any system users (other than root) from looking into the file.



<DL>

	<DT></DT>

</DL>





<DL>

	<DD>

<HR>

<A NAME="Heading6<FONT COLOR="#000077"><B>NOTE:</B> </FONT>Not all remote sites

	need a password for entry through UUCP. For example, some public archives let you

	log in and retrieve files using the <TT>uucp</TT> login with no password. Some sites

	use readily available passwords, such as <TT>uucp</TT>.

<HR>



</DL>



<P>The port name used in the <TT>/usr/lib/uucp/sys</TT> entry does not have to match

a device name on the Linux system, because another file is used to match the entry