<HTML ><HEAD ><TITLE >Remote Serial Console HOWTO</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="NEXT" TITLE="Introduction" HREF="intro.html"><META NAME="KEYWORD" CONTENT="serial console"><META NAME="KEYWORD" CONTENT="console"><META NAME="KEYWORD" CONTENT="serial"><META NAME="KEYWORD" CONTENT="modem"><META NAME="KEYWORD" CONTENT="RS-232"></HEAD ><BODY CLASS="BOOK" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="BOOK" ><A NAME="REMOTE-SERIAL-CONSOLE-HOWTO" ></A ><DIV CLASS="TITLEPAGE" ><H1 CLASS="TITLE" ><A NAME="AEN2" ></A >Remote Serial Console HOWTO</H1 ><H3 CLASS="AUTHOR" ><A NAME="AEN6" ></A >Glen Turner</H3 ><DIV CLASS="AFFILIATION" ><SPAN CLASS="ORGNAME" >Australian Academic and Research Network<BR></SPAN ><DIV CLASS="ADDRESS" ><P CLASS="ADDRESS" ><TT CLASS="EMAIL" ><<A HREF="mailto:glen.turner+howto@aarnet.edu.au" >glen.turner+howto@aarnet.edu.au</A >></TT ></P ></DIV ></DIV ><H3 CLASS="AUTHOR" ><A NAME="AEN13" ></A >Mark F. Komarinski</H3 ><DIV CLASS="AFFILIATION" ><DIV CLASS="ADDRESS" ><P CLASS="ADDRESS" ><TT CLASS="EMAIL" ><<A HREF="mailto:mkomarinskiATwayga.org" >mkomarinskiATwayga.org</A >></TT ></P ></DIV ></DIV ><P CLASS="PUBDATE" >v2.6 2003-03-31<BR></P ><DIV CLASS="REVHISTORY" ><TABLE WIDTH="100%" BORDER="0" ><TR ><TH ALIGN="LEFT" VALIGN="TOP" COLSPAN="3" ><B >Revision History</B ></TH ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.6</TD ><TD ALIGN="LEFT" >2003-03-31</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Correct opposing CTS/RTS explanations. Use <quote> in markup. TLDP PDF is now good, so remove instructions for rendering PostScript to PDF. Typo in GRUB configuration.</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.5</TD ><TD ALIGN="LEFT" >2003-01-20</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Only one console per technology type. Setting timezone. Use off parameter rather than comments in inittab. Cable lengths.</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.4</TD ><TD ALIGN="LEFT" >2002-10-03</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Kernel flow control bug, more cabling, Debian, Livingston Portmaster, typos (especially those found during translation to Japanese).</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.3</TD ><TD ALIGN="LEFT" >2002-07-11</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Updates for Red Hat Linux 7.3, corrections to serial port speeds and UARTs, ioctlsave.</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.2</TD ><TD ALIGN="LEFT" >2002-05-22</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Minor changes</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.1</TD ><TD ALIGN="LEFT" >2002-05-16</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Corrections to kernel console syntax. Addition of USB and devfs.</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision 2.0</TD ><TD ALIGN="LEFT" >2002-02-02</TD ><TD ALIGN="LEFT" >Revised by: gdt</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >Second edition.</TD ></TR ><TR ><TD ALIGN="LEFT" >Revision ≤1.0</TD ><TD ALIGN="LEFT" >2001-03-20</TD ><TD ALIGN="LEFT" >Revised by: mfk</TD ></TR ><TR ><TD ALIGN="LEFT" COLSPAN="3" >First edition.</TD ></TR ></TABLE ></DIV ><DIV ><DIV CLASS="ABSTRACT" ><A NAME="AEN61" ></A ><P ></P ><P >An <SPAN CLASS="ACRONYM" >RS-232</SPAN > serial console allows <SPAN CLASS="SYSTEMITEM" >Linux</SPAN > to be controlled from a terminal or modem attached to an asynchronous serial port. The monitor, mouse and keyboard are no longer required for system administration. Serial consoles are useful where <SPAN CLASS="SYSTEMITEM" >Linux</SPAN > systems are deployed at remote sites or are deployed in high-density racks.</P ><P >This <I CLASS="CITETITLE" >HOWTO</I > describes how to configure <SPAN CLASS="SYSTEMITEM" >Linux</SPAN > to attach a serial console.</P ><P ></P ></DIV ></DIV ><HR></DIV ><H1 ><A NAME="DEDICATION" ></A >Dedication</H1 ><P >Glen Turner would like to thank his family for allowing him to work on this project for the surprisingly large number of evenings which it took to write this <I CLASS="CITETITLE" >HOWTO</I >. Thank you Karen, Kayla and Ella.</P ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT >1. <A HREF="intro.html" >Introduction</A ></DT ><DD ><DL ><DT >1.1. <A HREF="intro-what.html" >What is a console?</A ></DT ><DT >1.2. <A HREF="intro-why.html" >Why use a serial console?</A ></DT ><DT >1.3. <A HREF="intro-word.html" >Alternative meanings of <SPAN CLASS="QUOTE" >"console"</SPAN ></A ></DT ><DT >1.4. <A HREF="intro-config.html" >Configuration overview</A ></DT ></DL ></DD ><DT >2. <A HREF="preparation.html" >Preparation</A ></DT ><DD ><DL ><DT >2.1. <A HREF="preparation-fallback.html" >Create fallback position</A ></DT ><DT >2.2. <A HREF="preparation-setport.html" >Select a serial port</A ></DT ><DT >2.3. <A HREF="preparation-setspeed.html" >Select a serial speed and parameters</A ></DT ><DT >2.4. <A HREF="preparation-modem.html" >Configure the modem or the null-modem cable</A ></DT ><DT >2.5. <A HREF="preparation-terminal.html" >Configure the terminal or the terminal emulator</A ></DT ></DL ></DD ><DT >3. <A HREF="bios.html" >Optionally configure the <SPAN CLASS="ACRONYM" >BIOS</SPAN ></A ></DT ><DT >4. <A HREF="configure-boot-loader.html" >Configure the boot loader</A ></DT ><DD ><DL ><DT >4.1. <A HREF="configure-boot-loader-lilo.html" >Configure the <SPAN CLASS="APPLICATION" >LILO</SPAN > boot loader</A ></DT ><DT >4.2. <A HREF="configure-boot-loader-grub.html" >Configure the <SPAN CLASS="APPLICATION" >GRUB</SPAN > boot loader</A ></DT ><DT >4.3. <A HREF="configure-boot-loader-syslinux.html" >Configure the <SPAN CLASS="APPLICATION" >SYSLINUX</SPAN > boot loader</A ></DT ></DL ></DD ><DT >5. <A HREF="configure-kernel.html" >Configure <SPAN CLASS="SYSTEMITEM" >Linux</SPAN > kernel</A ></DT ><DD ><DL ><DT >5.1. <A HREF="configure-kernel-lilo.html" >Configure Linux kernel using <SPAN CLASS="APPLICATION" >LILO</SPAN ></A ></DT ><DT >5.2. <A HREF="configure-kernel-grub.html" >Configure Linux kernel using <SPAN CLASS="APPLICATION" >GRUB</SPAN ></A ></DT ><DT >5.3. <A HREF="configure-kernel-syslinux.html" >Configure Linux kernel using <SPAN CLASS="APPLICATION" >SYSLINUX</SPAN ></A ></DT ></DL ></DD ><DT >6. <A HREF="getty.html" >Configure <SPAN CLASS="PRODUCTNAME" >getty</SPAN ></A ></DT ><DD ><DL ><DT >6.1. <A HREF="getty-init.html" ><SPAN CLASS="PRODUCTNAME" >init</SPAN > system</A ></DT ><DT >6.2. <A HREF="getty-getty.html" >Traditional <SPAN CLASS="PRODUCTNAME" >getty</SPAN ></A ></DT ><DT >6.3. <A HREF="getty-agetty.html" ><SPAN CLASS="PRODUCTNAME" >agetty</SPAN ></A ></DT ><DT >6.4. <A HREF="getty-mgetty.html" ><SPAN CLASS="PRODUCTNAME" >mgetty</SPAN ></A ></DT ><DT >6.5. <A HREF="getty-mingetty.html" ><SPAN CLASS="PRODUCTNAME" >mingetty</SPAN ></A ></DT ><DT >6.6. <A HREF="getty-none.html" >No <SPAN CLASS="PRODUCTNAME" >getty</SPAN ></A ></DT ></DL ></DD ><DT >7. <A HREF="misc.html" >Configure incidentals</A ></DT ><DD ><DL ><DT >7.1. <A HREF="misc-securetty.html" >Allow <SPAN CLASS="SYSTEMITEM" >root</SPAN > to login from serial console</A ></DT ><DT >7.2. <A HREF="misc-init.html" >Change <SPAN CLASS="APPLICATION" >init</SPAN > level to textual</A ></DT ><DT >7.3. <A HREF="misc-remove-ioctl-save.html" >Remove saved console settings</A ></DT ><DT >7.4. <A HREF="misc-devmodem.html" >Serial console is not <TT CLASS="FILENAME" >/dev/modem</TT ></A ></DT ><DT >7.5. <A HREF="misc-devsystty.html" >Alter target of <TT CLASS="FILENAME" >/dev/systty</TT ></A ></DT ><DT >7.6. <A HREF="misc-pam.html" >Configure Pluggable Authentication Modules</A ></DT ><DT >7.7. <A HREF="misc-configure-rhl.html" >Configure <SPAN CLASS="PRODUCTNAME" >Red Hat Linux</SPAN ></A ></DT ></DL ></DD ><DT >8. <A HREF="test.html" >Reboot and test</A ></DT ><DD ><DL ><DT >8.1. <A HREF="test-verify.html" >Verify console operation</A ></DT ><DT >8.2. <A HREF="recreate-ioctl-save.html" >Re-create saved console settings</A ></DT ><DT >8.3. <A HREF="test-console.html" >Test the console</A ></DT ><DT >8.4. <A HREF="end.html" >Where to next from here?</A ></DT ></DL ></DD ><DT >9. <A HREF="security.html" >Security</A ></DT ><DD ><DL ><DT >9.1. <A HREF="security-password.html" >Use good passwords</A ></DT ><DT >9.2. <A HREF="security-dtr.html" >Obey Data Terminal Ready and Data Carrier Detect</A ></DT ><DT >9.3. <A HREF="security-dumb.html" >Use or configure a dumb modem</A ></DT ><DT >9.4. <A HREF="security-messages.html" >Restrict console messages</A ></DT ><DT >9.5. <A HREF="security-modem.html" >Modem features to restrict usage</A ></DT ><DT >9.6. <A HREF="security-bios.html" ><SPAN CLASS="ACRONYM" >BIOS</SPAN > features</A ></DT ><DT >9.7. <A HREF="security-bootloader.html" >Use a boot loader password</A ></DT ><DT >9.8. <A HREF="security-rhl-prompt.html" >Non-interactive boot sequence</A ></DT ><DT >9.9. <A HREF="security-sysrq.html" >Magic <B CLASS="KEYCAP" >SysRq</B > key</A ></DT ><DT >9.10. <A HREF="security-ctrlaltdel.html" >Adjust behaviour of <B CLASS="KEYCAP" >Ctrl</B >-<B CLASS="KEYCAP" >Alt</B >-<B CLASS="KEYCAP" >Delete</B ></A ></DT ><DT >9.11. <A HREF="security-log.html" >Log attempted access</A ></DT ><DT >9.12. <A HREF="security-interception.html" >Countering interception of telephony links</A ></DT ></DL ></DD ><DT >10. <A HREF="kernelcompile.html" >Configuring a kernel to support serial console</A ></DT ><DD ><DL ><DT >10.1. <A HREF="kernelcompile-25.html" >Linux kernel version 2.5</A ></DT ><DT >10.2. <A HREF="kernelcompile-24.html" >Linux kernel version 2.4</A ></DT ><DT >10.3. <A HREF="kernelcompile-22.html" ><SPAN CLASS="SYSTEMITEM" >Linux</SPAN > kernel version 2.2</A ></DT ></DL ></DD ><DT >11. <A HREF="serial.html" >Serial cabling</A ></DT ><DD ><DL ><DT >11.1. <A HREF="serial-jargon.html" >Jargon</A ></DT ><DT >11.2. <A HREF="serial-pc-modem.html" >Cable from console port to modem</A ></DT ><DT >11.3. <A HREF="serial-pc-terminal.html" >Cable from console port to terminal (or another PC)</A ></DT ><DT >11.4. <A HREF="serial-distance.html" >Lengths of serial cables</A ></DT ><DT >11.5. <A HREF="serial-manufacture.html" >Making serial cables</A ></DT ></DL ></DD ><DT >12. <A HREF="modem.html" >Modem configuration</A ></DT ><DD ><DL ><DT >12.1. <A HREF="modem-minicom.html" >Using <SPAN CLASS="PRODUCTNAME" >Minicom</SPAN > to give commands to a modem</A ></DT ><DT >12.2. <A HREF="modem-dumb.html" >Configure dumb modem</A ></DT ><DT >12.3. <A HREF="modem-hayes.html" >Configure modem with <SPAN CLASS="ACRONYM" >AT</SPAN > commands</A ></DT ><DT >12.4. <A HREF="modem-internal.html" >Internal modems</A ></DT ><DT >12.5. <A HREF="modem-dsp.html" >WinModems</A ></DT ></DL ></DD ><DT >A. <A HREF="bugs.html" >Bugs and annoyances</A ></DT ><DD ><DL ><DT >A.1. <A HREF="bugs-kernelp.html" >Flow control in <SPAN CLASS="SYSTEMITEM" >Linux</SPAN > kernel</A ></DT ><DT >A.2. <A HREF="bugs-rhl71.html" ><SPAN CLASS="PRODUCTNAME" >Red Hat <SPAN CLASS="SYSTEMITEM" >Linux</SPAN ></SPAN > <SPAN CLASS="PRODUCTNUMBER" >7.1</SPAN > and SysVinit</A ></DT ><DT >A.3. <A HREF="bugs-video.html" ><SPAN CLASS="ACRONYM" >BIOS</SPAN >s, keyboards and video cards</A ></DT ><DT >A.4. <A HREF="bugs-reboot.html" >Modem hangs up upon reboot</A ></DT ><DT >A.5. <A HREF="bugs-monitor.html" ><SPAN CLASS="APPLICATION" >init</SPAN > and <SPAN CLASS="APPLICATION" >syslog</SPAN > output does not display on secondary consoles</A ></DT ><DT >A.6. <A HREF="bugs-whereami.html" >The console is unresponsive after connecting</A ></DT ><DT >A.7. <A HREF="bugs-setserial.html" >Modem hangs up during initialization</A ></DT ><DT >A.8. <A HREF="bugs-bootloaderflow.html" >Boot loader has no flow control</A ></DT ><DT >A.9. <A HREF="bugs-bootloadernoise.html" >Boot loaders are vulnerable to line noise</A ></DT ><DT >A.10. <A HREF="bugs-apm.html" ><SPAN CLASS="PRODUCTNAME" >Advanced Power Management</SPAN ></A ></DT ><DT >A.11. <A HREF="bugs-international.html" >Modems and overseas telecommunications requirements</A ></DT ></DL ></DD ><DT >B. <A HREF="upload.html" >Uploading files from a serial console</A ></DT ><DD ><DL ><DT >B.1. <A HREF="upload-logging.html" >Disable logging to console</A ></DT ><DT >B.2. <A HREF="upload-cat.html" ><SPAN CLASS="ACRONYM" >ASCII</SPAN > upload and <B CLASS="COMMAND" >cat</B ></A ></DT ><DT >B.3. <A HREF="upload-zmodem.html" ><SPAN CLASS="APPLICATION" >Xmodem</SPAN >, <SPAN CLASS="APPLICATION" >Ymodem</SPAN > and <SPAN CLASS="APPLICATION" >Zmodem</SPAN ></A ></DT ><DT >B.4. <A HREF="upload-kermit.html" ><SPAN CLASS="APPLICATION" >Kermit</SPAN ></A ></DT ></DL ></DD ><DT >C. <A HREF="rhl.html" >Upgrading <SPAN CLASS="PRODUCTNAME" >Red Hat Linux</SPAN > from a serial console</A ></DT ><DD ><DL ><DT >C.1. <A HREF="rhl-selectboot.html" >Select boot disk</A ></DT ><DT >C.2. <A HREF="rhl-biosserial.html" >Configure the <SPAN CLASS="ACRONYM" >BIOS</SPAN > to use the serial port</A ></DT ><DT >C.3. <A HREF="rhl-ignoredtr.html" >Configure modem to ignore <SPAN CLASS="ACRONYM" >DTR</SPAN > and assert <SPAN CLASS="ACRONYM" >DCD</SPAN ></A ></DT ><DT >C.4. <A HREF="rhl-preparefloppy.html" >Prepare a network install floppy diskette</A ></DT ><DT >C.5. <A HREF="rhl-preparehttp.html" >Prepare <SPAN CLASS="ACRONYM" >HTTP</SPAN > server</A ></DT ><DT >C.6. <A HREF="rhl-ifconfig.html" >Record network configuration</A ></DT ><DT >C.7. <A HREF="rhl-liloconfig.html" >Record LILO configuration</A ></DT ><DT >C.8. <A HREF="rhl-upgrade.html" >Upgrade Red Hat distribution</A ></DT ><DT >C.9. <A HREF="rhbootdisk.html" >Create boot disk for serial console</A ></DT ><DT >C.10. <A HREF="rhreferences.html" >Further references</A ></DT ></DL ></DD ><DT >D. <A HREF="debian.html" >Upgrading <SPAN CLASS="PRODUCTNAME" >Debian <SPAN CLASS="ACRONYM" >GNU</SPAN >/Linux</SPAN > from a serial console</A ></DT ><DT >E. <A HREF="ts.html" >Terminal server configuration</A ></DT ><DD ><DL ><DT >E.1. <A HREF="ts-buy.html" >Considerations when buying second-hand terminal servers</A ></DT ><DT >E.2. <A HREF="ts-cisco2511.html" ><SPAN CLASS="PRODUCTNAME" >Cisco 2511</SPAN ></A ></DT ><DT >E.3. <A HREF="ts-maxserver.html" >Xyplex/iTouch <SPAN CLASS="PRODUCTNAME" >MAXserver 1600</SPAN ></A ></DT ><DT >E.4. <A HREF="ts-annex.html" >Xylogics/Bay/Nortel <SPAN CLASS="PRODUCTNAME" >Annex</SPAN ></A ></DT ><DT >E.5. <A HREF="ts-pm.html" >Livingston/Lucent <SPAN CLASS="PRODUCTNAME" >Portmaster</SPAN ></A ></DT ></DL ></DD ><DT >F. <A HREF="advice.html" >Gratuitous advice for developers</A ></DT ><DD ><DL ><DT >F.1. <A HREF="advice-bootloader.html" >Advice for boot loader authors</A ></DT ><DT >F.2. <A HREF="advice-bios.html" >Advice for <SPAN CLASS="ACRONYM" >BIOS</SPAN > authors</A ></DT ></DL ></DD ><DT >G. <A HREF="about.html" >About this HOWTO</A ></DT ><DD ><DL ><DT >G.1. <A HREF="about-copyright.html" >Copyright</A ></DT ><DT >G.2. <A HREF="about-disclaimer.html" >Disclaimer</A ></DT ><DT >G.3. <A HREF="about-credits.html" >Acknowledgments</A ></DT ><DT >G.4. <A HREF="about-feedback.html" >Comments and corrections</A ></DT ></DL ></DD ><DT ><A HREF="colophon.html" >Colophon</A ></DT ></DL ></DIV ><DIV CLASS="LOT" ><DL CLASS="LOT" ><DT ><B >List of Tables</B ></DT ><DT >1-1. <A HREF="intro-word.html#INTRO-WORD-CONSOLE" >Different ways of referring to the <SPAN CLASS="QUOTE" >"console"</SPAN ></A ></DT ><DT >2-1. <A HREF="preparation-setport.html#PREPARATION-SETPORT-NAMES-MANY" >Many names for the same serial port</A ></DT ><DT >2-2. <A HREF="preparation-setport.html#PREPARATION-SETPORT-IBMPC" >Interrupts used for <SPAN CLASS="PRODUCTNAME" ><SPAN CLASS="ACRONYM" >IBM</SPAN > <SPAN CLASS="ACRONYM" >PC/AT</SPAN ></SPAN > <SPAN CLASS="ACRONYM" >RS-232</SPAN > ports</A ></DT ><DT >4-1. <A HREF="configure-boot-loader-syslinux.html#CONFIGURE-BOOT-LOADER-SYSLINUX-FLOWCONTROL" ><SPAN CLASS="PRODUCTNAME" >SYSLINUX</SPAN > flow control bitmap</A ></DT ><DT >10-1. <A HREF="kernelcompile-22.html#KERNELCOMPILE-22-DIVISORS" ><SPAN CLASS="ACRONYM" >IBM-PC/AT</SPAN > serial port bit rates and their bit-clock divisors</A ></DT ><DT >11-1. <A HREF="serial-distance.html#SERIAL-MANUFACTURE-DISTANCE" >Data rates and the maximum distances recommended in RS-232</A ></DT ></DL ></DIV ><DIV CLASS="LOT" ><DL CLASS="LOT" ><DT ><B >List of Figures</B ></DT ><DT >2-1. <A HREF="preparation-setport.html#PREPARATION-SETPORT-SETSERIAL" >Using the <B CLASS="COMMAND" >setserial</B > command in <TT CLASS="FILENAME" >/etc/rc.serial</TT >to disable the serial port <TT CLASS="FILENAME" >/dev/ttyS2</TT ></A ></DT ><DT >2-2. <A HREF="preparation-setspeed.html#PREPARATION-SETSPEED-BPS" >Syntax for serial bits per second rate, in extended Backus-Naur form</A ></DT ><DT >2-3. <A HREF="preparation-setspeed.html#PREPARATION-SETSPEED-PARITY" >Syntax for serial parity, in extended Backus-Naur form</A ></DT ><DT >2-4. <A HREF="preparation-setspeed.html#PREPARATION-SETSPEED-DATA" >Syntax for serial data bits, in extended Backus-Naur form</A ></DT ><DT >2-5. <A HREF="preparation-setspeed.html#PREPARATION-SETSPEED-STOP" >Syntax for serial stop bits, in extended Backus-Naur form</A ></DT ><DT >2-6. <A HREF="preparation-setspeed.html#PREPARATION-SETSPEED-FLOW" >Syntax for serial flow control, in extended Backus-Naur form</A ></DT ><DT >2-7. <A HREF="preparation-setspeed.html#PREPARATION-SETSPEED-MODESYNTAX" >Syntax for kernel serial parameters, in extended Backus-Naur form</A ></DT ><DT >4-1. <A HREF="configure-boot-loader-lilo.html#CONFIGURE-BOOT-LOADER-LILO-SYNTAX" >Syntax of <SPAN CLASS="PRODUCTNAME" >LILO</SPAN > <B CLASS="COMMAND" >serial</B > command, in <SPAN CLASS="ACRONYM" >EBNF</SPAN ></A ></DT ><DT >4-2. <A HREF="configure-boot-loader-lilo.html#CONFIGURE-BOOT-LOADER-LILO-EBNF" ><SPAN CLASS="PRODUCTNAME" >LILO</SPAN > <B CLASS="COMMAND" >serial</B > <SPAN CLASS="ACRONYM" >EBNF</SPAN > variables</A ></DT ><DT >4-3. <A HREF="configure-boot-loader-lilo.html#CONFIGURE-BOOT-LOADER-LILO-CONFIGURATION" ><SPAN CLASS="APPLICATION" >LILO</SPAN > boot loader sample configuration</A ></DT ><DT >4-4. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-MD5" >Using <B CLASS="COMMAND" >md5crypt</B > to create a hashed password for <SPAN CLASS="APPLICATION" >GRUB</SPAN ></A ></DT ><DT >4-5. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-PASSWORD" ><SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration to require a password</A ></DT ><DT >4-6. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-SERIAL" ><SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration for serial console</A ></DT ><DT >4-7. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-SERIALCONSOLE" ><SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration for serial console and attached monitor and keybaord console</A ></DT ><DT >4-8. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-PRESS" >GRUB output to default device when configured for serial and attached monior output</A ></DT ><DT >4-9. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-DUMB" ><SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration for command line interface for terminals other than <SPAN CLASS="PRODUCTNAME" >VT100</SPAN ></A ></DT ><DT >4-10. <A HREF="configure-boot-loader-grub.html#CONFIGURE-BOOT-LOADER-GRUB-RUNLEVEL" >Adding a single user mode option to the <SPAN CLASS="APPLICATION" >GRUB</SPAN > menu</A ></DT ><DT >4-11. <A HREF="configure-boot-loader-syslinux.html#CONFIGURE-BOOT-LOADER-SYSLINUX-SERIAL-SYNTAX" >Syntax of <SPAN CLASS="PRODUCTNAME" >SYSLINUX</SPAN > <B CLASS="COMMAND" >serial</B > command, in <SPAN CLASS="ACRONYM" >EBNF</SPAN ></A ></DT ><DT >4-12. <A HREF="configure-boot-loader-syslinux.html#CONFIGURE-BOOT-LOADER-SYSLINUX-EBNF" ><SPAN CLASS="PRODUCTNAME" >SYSLINUX</SPAN > <B CLASS="COMMAND" >serial</B > <SPAN CLASS="ACRONYM" >EBNF</SPAN > variables</A ></DT ><DT >5-1. <A HREF="configure-kernel.html#CONFIGURE-KERNEL-SYNTAX" >Kernel <TT CLASS="LITERAL" >console</TT > syntax, in EBNF</A ></DT ><DT >5-2. <A HREF="configure-kernel.html#CONFIGURE-KERNEL-PARAMETERS-VIDEO" >Recommended kernel parameters, <SPAN CLASS="ACRONYM" >PC</SPAN >s with video card</A ></DT ><DT >5-3. <A HREF="configure-kernel.html#CONFIGURE-KERNEL-PARAMETERS-NOVIDEO" >Recommended kernel parameters, <SPAN CLASS="ACRONYM" >PC</SPAN >s without video card</A ></DT ><DT >5-4. <A HREF="configure-kernel-lilo.html#CONFIGURE-KERNEL-LILO-PARAMETERS" >Recommended kernel parameters, <SPAN CLASS="APPLICATION" >LILO</SPAN > configuration</A ></DT ><DT >5-5. <A HREF="configure-kernel-grub.html#CONFIGURE-KERNEL-GRUB-KERNEL-AFTER" >Recommened kernel parameters, <SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration</A ></DT ><DT >5-6. <A HREF="configure-kernel-syslinux.html#CONFIGURE-KERNEL-SYSLINUX-APPEND" >Recommended kernel parameters, <SPAN CLASS="APPLICATION" >SYSLINUX</SPAN > configuration</A ></DT ><DT >6-1. <A HREF="getty.html#GETTY-TERM" >Interactively altering the connecting terminal's make and model</A ></DT ><DT >6-2. <A HREF="getty.html#GETTY-TZ" >Interactively altering the connecting terminal's time zone</A ></DT ><DT >6-3. <A HREF="getty-init.html#GETTY-INIT-INITTAB" ><SPAN CLASS="APPLICATION" >getty</SPAN > is started by <SPAN CLASS="APPLICATION" >init</SPAN >, based upon an entry in <TT CLASS="FILENAME" >/etc/inittab</TT ></A ></DT ><DT >6-4. <A HREF="getty-getty.html#GETTY-GETTY-GETTYDEFS" >Define <TT CLASS="LITERAL" >CON9600</TT > in <TT CLASS="FILENAME" >gettydefs</TT ></A ></DT ><DT >6-5. <A HREF="getty-getty.html#GETTY-GETTY-GETTYDEFS-SYNTAX" >Syntax of entries in <TT CLASS="FILENAME" >/etc/gettydefs</TT >, in EBNF</A ></DT ><DT >6-6. <A HREF="getty-agetty.html#GETTY-AGETTY-INITTAB" ><TT CLASS="FILENAME" >/etc/inittab</TT > entry for <SPAN CLASS="APPLICATION" >agetty</SPAN ></A ></DT ><DT >6-7. <A HREF="getty-mgetty.html#GETTY-MGETTY-INITTAB" ><TT CLASS="FILENAME" >/etc/inittab</TT > entry for <SPAN CLASS="APPLICATION" >mgetty</SPAN ></A ></DT ><DT >6-8. <A HREF="getty-mgetty.html#AEN1687" ><SPAN CLASS="APPLICATION" >mgetty</SPAN > configuration file <TT CLASS="FILENAME" >mgetty.config</TT ></A ></DT ><DT >6-9. <A HREF="getty-mingetty.html#GETTY-MINGETTY-INITTAB" >Fewer virtual terminals. Removing <SPAN CLASS="APPLICATION" >mingetty</SPAN > entries from <TT CLASS="FILENAME" >/etc/inittab</TT ></A ></DT ><DT >6-10. <A HREF="getty-mingetty.html#GETTY-MINGETTY-DEVTTY" >Fewer virtual terminals. Deallocating unused virtual terminals and removing their device files.</A ></DT ><DT >6-11. <A HREF="getty-none.html#GETTY-NONE-RCSERIAL" >Contents of <TT CLASS="FILENAME" >/etc/rc.serial</TT > to lock console serial port when no <SPAN CLASS="APPLICATION" >getty</SPAN > used</A ></DT ><DT >7-1. <A HREF="misc-securetty.html#MISC-SECRETTY-TTYS0" >Alter <TT CLASS="FILENAME" >securetty</TT > to allow <SPAN CLASS="SYSTEMITEM" >root</SPAN > to log in from the serial console</A ></DT ><DT >7-2. <A HREF="misc-init.html#MISC-INIT-X11-XSERVERS" ><TT CLASS="FILENAME" >Xservers</TT > from Red Hat Linux 7.2</A ></DT ><DT >7-3. <A HREF="misc-init.html#MISC-INIT-X11-GDMCONF" ><TT CLASS="LITERAL" >[servers]</TT > section of <TT CLASS="FILENAME" >gdm.conf</TT > from Red Hat Linux 7.2</A ></DT ><DT >7-4. <A HREF="misc-remove-ioctl-save.html#REMOVE-IOCTL-SAVE-RM" >Removal of <TT CLASS="FILENAME" >ioctl.save</TT > containing the saved console parameters</A ></DT ><DT >7-5. <A HREF="misc-devmodem.html#MISC-DEVMODEM-EXAMPLE" >Remove <TT CLASS="FILENAME" >/dev/modem</TT > if it points to the serial console's port</A ></DT ><DT >7-6. <A HREF="misc-devsystty.html#MISC-DEVSYSTTY-DEFAULT" >Default value of <TT CLASS="FILENAME" >/dev/systty</TT > in <TT CLASS="FILENAME" >/etc/makedev.d/linux-2.4.x</TT ></A ></DT ><DT >7-7. <A HREF="misc-devsystty.html#MISC-DEVSYSTTY-SERIAL" >Alter value of <TT CLASS="FILENAME" >/dev/systty</TT > in <B CLASS="COMMAND" >MAKEDEV</B > configuration file</A ></DT ><DT >7-8. <A HREF="misc-devsystty.html#MISC-DEVSYSTTY-CREATE" >Installing new value of <TT CLASS="FILENAME" >/dev/systty</TT ></A ></DT ><DT >7-9. <A HREF="misc-pam.html#MISC-PAM-DEFAULT-CONSOLE" >Default <TT CLASS="LITERAL" ><console></TT > in <TT CLASS="FILENAME" >console.perms</TT > refers to attached keyboard and screen</A ></DT ><DT >7-10. <A HREF="misc-pam.html#MISC-PAM-DEFAULT-DEV" >Default device listing in <TT CLASS="FILENAME" >console.perms</TT ></A ></DT ><DT >7-11. <A HREF="misc-pam.html#MISC-PAM-SERIAL-DEV" >Devices in <TT CLASS="FILENAME" >console.perms</TT > required for attached keyboard and screen</A ></DT ><DT >7-12. <A HREF="misc-pam.html#MISC-PAM-SERIAL-SCONSOLE" >Add <TT CLASS="LITERAL" ><sconsole></TT > in <TT CLASS="FILENAME" >console.perms</TT > to refer to serial console</A ></DT ><DT >7-13. <A HREF="misc-pam.html#MISC-PAM-SERIAL-SDEV" >Remaining devices in <TT CLASS="FILENAME" >console.perms</TT > altered to refer to serial console</A ></DT ><DT >7-14. <A HREF="misc-configure-rhl.html#MISC-CONFIGURE-RHL-ETC-SYSLINUX-INIT" >Alterations to <TT CLASS="FILENAME" >/etc/sysconfig/init</TT > for <SPAN CLASS="PRODUCTNAME" >Red Hat Linux</SPAN ></A ></DT ><DT >7-15. <A HREF="misc-configure-rhl.html#MISC-CONFIGURE-RHL-ETC-SYSLINUX-KUDZU" >Alterations to <TT CLASS="FILENAME" >/etc/sysconfig/kudzu</TT > for <SPAN CLASS="PRODUCTNAME" >Red Hat Linux</SPAN ></A ></DT ><DT >8-1. <A HREF="recreate-ioctl-save.html#RECREATE-IOCTL-SAVE-IOCTLSAVE" >Using <B CLASS="COMMAND" >ioctlsave</B > to create <TT CLASS="FILENAME" >/etc/ioctl.save</TT > without entering single user mode</A ></DT ><DT >9-1. <A HREF="security.html#SECURITY-LEYDEN" >Extract from Crackers favour war dialling and weak passwords</A ></DT ><DT >9-2. <A HREF="security-messages.html#SECURITY-MESSAGES-SYSLOGCONF" ><TT CLASS="FILENAME" >/etc/syslog.conf</TT > modified to copy log messages to a log server</A ></DT ><DT >9-3. <A HREF="security-messages.html#SECURITY-MESSAGES-SYSCONFIG" >Allowing remote log messages by setting options in <TT CLASS="FILENAME" >/etc/sysconfig/syslog</TT ></A ></DT ><DT >9-4. <A HREF="security-messages.html#SECURITY-MESSAGES-IPTABLES" >Restrict <SPAN CLASS="APPLICATION" >syslog</SPAN > messages to <SPAN CLASS="SYSTEMITEM" >remote.example.edu.au</SPAN ></A ></DT ><DT >9-5. <A HREF="security-messages.html#SECURITY-MESSAGES-NSCD" >Using <SPAN CLASS="APPLICATION" >nscd</SPAN > to cache reverse <SPAN CLASS="ACRONYM" >DNS</SPAN > lookups</A ></DT ><DT >9-6. <A HREF="security-messages.html#SECURITY-MESSAGES-SHLONG" >Restrict sending of messages to console user</A ></DT ><DT >9-7. <A HREF="security-messages.html#SECURITY-MESSAGES-SH" >Restrict sending of messages to console user, <TT CLASS="FILENAME" >/etc/profile.d/mesg.sh</TT ></A ></DT ><DT >9-8. <A HREF="security-messages.html#SECURITY-MESSAGES-CSH" >Restrict sending of messages to console user, <TT CLASS="FILENAME" >/etc/profile.d/mesg.csh</TT ></A ></DT ><DT >9-9. <A HREF="security-messages.html#SECURITY-MESSAGES-INSTALL" >Install files into <TT CLASS="FILENAME" >/etc/profile.d</TT ></A ></DT ><DT >9-10. <A HREF="security-sysrq.html#SECURITY-SYSRQ-SYSCTL" >Using <B CLASS="COMMAND" >sysctl</B > to defeat the magic <B CLASS="KEYCAP" >SysRq</B > key</A ></DT ><DT >9-11. <A HREF="security-sysrq.html#SECURITY-SYSRQ-SYSCTLCONF" >Configuring <TT CLASS="FILENAME" >/etc/sysctl.conf</TT > to defeat the magic <B CLASS="KEYCAP" >SysRq</B > key</A ></DT ><DT >9-12. <A HREF="security-sysrq.html#SECURITY-SYSRQ-MENUCONFIG" >Kernel <B CLASS="COMMAND" >make menuconfig</B > showing disabled <B CLASS="KEYCAP" >SysRq</B > key</A ></DT ><DT >9-13. <A HREF="security-sysrq.html#SECURITY-SYSRQ-DOTCONFIG" >Kernel <TT CLASS="FILENAME" >.config</TT > showing disabled <B CLASS="KEYCAP" >SysRq</B > key</A ></DT ><DT >9-14. <A HREF="security-ctrlaltdel.html#SECURITY-CTRLALTDEL-TELINIT-DEFAULT" >Default handling of <B CLASS="KEYCAP" >Ctrl</B >-<B CLASS="KEYCAP" >Alt</B >-<B CLASS="KEYCAP" >Delete</B > in <TT CLASS="FILENAME" >/etc/inittab</TT ></A ></DT ><DT >9-15. <A HREF="security-ctrlaltdel.html#SECURITY-CTRLALTDEL-TELINIT-IGNORE" >Ignoring <B CLASS="KEYCAP" >Ctrl</B >-<B CLASS="KEYCAP" >Alt</B >-<B CLASS="KEYCAP" >Delete</B > in <TT CLASS="FILENAME" >/etc/inittab</TT ></A ></DT ><DT >9-16. <A HREF="security-ctrlaltdel.html#SECURITY-CTRLALTDEL-TELINIT-HALT" >Shut down cleanly upon <B CLASS="KEYCAP" >Ctrl</B >-<B CLASS="KEYCAP" >Alt</B >-<B CLASS="KEYCAP" >Delete</B > in <TT CLASS="FILENAME" >/etc/inittab</TT ></A ></DT ><DT >10-1. <A HREF="kernelcompile-25.html#KERNELCOMPILE-25-MENUCONFIG" >Kernel configuration for serial console using <B CLASS="COMMAND" >make menuconfig</B ></A ></DT ><DT >10-2. <A HREF="kernelcompile-25.html#KERNELCOMPILE-25-DOTCONFIG" >Kernel configuration for serial console using <TT CLASS="FILENAME" >.config</TT ></A ></DT ><DT >10-3. <A HREF="kernelcompile-25.html#KERNELCOMPILE-25-USB-MENUCONFIG" >Kernel configuration for <SPAN CLASS="ACRONYM" >USB</SPAN > dongle serial console using <B CLASS="COMMAND" >make menuconfig</B ></A ></DT ><DT >10-4. <A HREF="kernelcompile-25.html#KERNELCOMPILE-25-USB-DOTCONFIG" >Kernel configuration for <SPAN CLASS="ACRONYM" >USB</SPAN > dongle serial console using <TT CLASS="FILENAME" >.config</TT ></A ></DT ><DT >10-5. <A HREF="kernelcompile-24.html#KERNELCOMPILE-24-MENUCONFIG" >Kernel configuration for serial console using <B CLASS="COMMAND" >make menuconfig</B ></A ></DT ><DT >10-6. <A HREF="kernelcompile-24.html#KERNELCOMPILE-24-DOTCONFIG" >Kernel configuration for serial console using <TT CLASS="FILENAME" >.config</TT ></A ></DT ><DT >11-1. <A HREF="serial-pc-terminal.html#SERIAL-PC-TERMINAL-CABLE-GOOD1" >Null modem cable with full status and handshaking</A ></DT ><DT >11-2. <A HREF="serial-pc-terminal.html#SERIAL-PC-TERMINAL-CABLE-GOOD2" >Variation on null modem cable with full status and handshaking</A ></DT ><DT >11-3. <A HREF="serial-pc-terminal.html#SERIAL-PC-TERMINAL-CABLE-BAD" >Null modem cable with falsified status and handshaking</A ></DT ><DT >11-4. <A HREF="serial-pc-terminal.html#SERIAL-PC-TERMINAL-CABLE-UGLY1" >Null modem cable with no status or handshaking</A ></DT ><DT >11-5. <A HREF="serial-pc-terminal.html#SERIAL-PC-TERMINAL-CABLE-UGLY2" >One-way null modem cable with no status or handshaking</A ></DT ><DT >12-1. <A HREF="modem-dumb.html#MODEM-DUMB-FRONT" >Front panel of a dumb modem</A ></DT ><DT >12-2. <A HREF="modem-hayes.html#MODEM-HAYES-BPS-ATI" >Testing the modem's port speed</A ></DT ><DT >12-3. <A HREF="modem-hayes.html#MODEM-HAYES-EXAMPLE-CONFIG" >Configure modem using <SPAN CLASS="ACRONYM" >AT</SPAN > commands</A ></DT ><DT >12-4. <A HREF="modem-hayes.html#MODEM-HAYES-ATTENTION-REGAIN" >Resetting a Hayes <SPAN CLASS="ACRONYM" >AT</SPAN >-style modem</A ></DT ><DT >A-1. <A HREF="bugs-kernelp.html#BUGS-KERNELP-CONFIG" >A kernel <TT CLASS="LITERAL" >console</TT > parameter with <SPAN CLASS="ACRONYM" >CTS</SPAN >/<SPAN CLASS="ACRONYM" >RTS</SPAN > flow control</A ></DT ><DT >A-2. <A HREF="bugs-kernelp.html#BUGS-KERNELP-SERIALC" >Kernel source code for console <SPAN CLASS="ACRONYM" >CTS</SPAN >/<SPAN CLASS="ACRONYM" >RTS</SPAN > flow control</A ></DT ><DT >A-3. <A HREF="bugs-setserial.html#BUGS-SETSERIAL-INIT" ><B CLASS="COMMAND" >setserial</B > causes a modem to hang up as the machine initializes</A ></DT ><DT >B-1. <A HREF="upload-logging.html#AEN3363" >Supressing kernel messages to the console in Red Hat Linux</A ></DT ><DT >C-1. <A HREF="rhl-biosserial.html#RHL-BIOSSERIAL-EXAMPLE" >Configuring <SPAN CLASS="ACRONYM" >BIOS</SPAN > to use serial link</A ></DT ><DT >C-2. <A HREF="rhl-biosserial.html#RHL-BIOSSERIAL-BOOTORDER" >Configuring BIOS to boot from hard disk</A ></DT ><DT >C-3. <A HREF="rhbootdisk.html#RHBOOTDISK-MKBOOTDISK-ORIGINAL" >Extract from Red Hat Linux 7.2 <TT CLASS="FILENAME" >mkbootdisk</TT > which creates <TT CLASS="FILENAME" >SYSLINUX.CFG</TT ></A ></DT ><DT >C-4. <A HREF="rhbootdisk.html#RHBOOTDISK-MKBOOTDISK-SERIAL" >Altered extract from <TT CLASS="FILENAME" >mkbootdisk</TT >, which creates a <TT CLASS="FILENAME" >SYSLINUX.CFG</TT > that uses a serial console</A ></DT ><DT >E-1. <A HREF="ts-cisco2511.html#TS-CISCO2511-CONFIG" >Basic configuration for <SPAN CLASS="PRODUCTNAME" >Cisco 2511</SPAN > terminal server to <SPAN CLASS="SYSTEMITEM" >Linux</SPAN > <SPAN CLASS="ACRONYM" >PC</SPAN ></A ></DT ><DT >E-2. <A HREF="ts-pm.html#TS-PM-BASIC" >Portmaster unit configuration</A ></DT ><DT >E-3. <A HREF="ts-pm.html#TS-PM-PORT" >Portmaster port configuration</A ></DT ><DT >F-1. <A HREF="advice-bios.html#ADVICE-BIOS-NVRAMCONFIG" >Configuring /dev/nvram to access the <SPAN CLASS="ACRONYM" >CMOS</SPAN > configuration</A ></DT ><DT >F-2. <A HREF="advice-bios.html#ADVICE-BIOS-NVRAMGET" >Getting the <SPAN CLASS="ACRONYM" >CMOS</SPAN > configuration</A ></DT ><DT >F-3. <A HREF="advice-bios.html#ADVICE-BIOS-NVRAMSET" >Setting the <SPAN CLASS="ACRONYM" >CMOS</SPAN > configuration</A ></DT ></DL ></DIV ><DIV CLASS="LOT" ><DL CLASS="LOT" ><DT ><B >List of Examples</B ></DT ><DT >4-1. <A HREF="configure-boot-loader-lilo.html#CONFIGURE-BOOT-LOADER-LILO-HACK" >Using kernel parameters to avoid access permissions</A ></DT ><DT >5-1. <A HREF="configure-kernel-lilo.html#CONFIGURE-KERNEL-LILO-RHL-VENDOR" >Complete <SPAN CLASS="APPLICATION" >LILO</SPAN > configuration, as installed by vendor</A ></DT ><DT >5-2. <A HREF="configure-kernel-lilo.html#CONFIGURE-KERNEL-LILO-RHL-SERIAL" >Complete <SPAN CLASS="APPLICATION" >LILO</SPAN > configuration, modified for serial console</A ></DT ><DT >5-3. <A HREF="configure-kernel-grub.html#CONFIGURE-KERNEL-GRUB-RHL-VENDOR" >Complete <SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration, as installed by vendor</A ></DT ><DT >5-4. <A HREF="configure-kernel-grub.html#CONFIGURE-KERNEL-GRUB-RHL-SERIAL" >Complete <SPAN CLASS="APPLICATION" >GRUB</SPAN > configuration, modified for serial console</A ></DT ><DT >8-1. <A HREF="test-console.html#TEST-CONSOLE-SESSION" >Dialing into a serial console</A ></DT ><DT >C-1. <A HREF="rhl-ifconfig.html#RHL-IFCONFIG-IFCONFIG" >Displaying the Internet Protocol configuration</A ></DT ><DT >C-2. <A HREF="rhl-liloconfig.html#RHL-LILOCONFIG-LILO" >Displaying the <SPAN CLASS="APPLICATION" >LILO</SPAN > configuration</A ></DT ></DL ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" > </TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="intro.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" > </TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Introduction</TD ></TR ></TABLE ></DIV ></BODY ></HTML >