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OpenBSD Frequently Asked Questions Language: en [teams] cs de fr nl pl Documentation and Frequently Other Documents Asked Questions Upgrade Guide Following -current Commonly Encountered Issues Recent updates Following -stable Port Testing Guide Using AnonCVS This FAQ is supplemental documentation to the man pages, available both Using CVSup in the installed system and online. The FAQ covers the active release of Manual pages OpenBSD, currently v4.4. There are likely features and changes to features in the development version (-current) of OpenBSD that are not covered in Bug Reporting this FAQ. Mailing lists PF User's Guide The FAQ in PDF and plain text form is available in the pub/OpenBSD/ OpenSSH FAQ doc directory from many FTP mirrors, along with archival versions. PDF files OpenBSD FAQ PF User's Guide Text files 1 - Introduction to OpenBSD OpenBSD FAQ PF User's Guide ● 1.1 - What is OpenBSD? Back to OpenBSD ● 1.2 - On what systems does OpenBSD run? ● 1.3 - Is OpenBSD really free? ● 1.4 - Why might I want to use OpenBSD? ● 1.5 - How can I help support OpenBSD? ● 1.6 - Who maintains OpenBSD? ● 1.7 - When is the next release of OpenBSD? ● 1.8 - What is included with OpenBSD? ● 1.9 - What is new in OpenBSD 4.4? ● 1.10 - Can I use OpenBSD as a desktop system? ● 1.11 - Why is/isn't ProductX included? 2 - Getting to know OpenBSD http://www.openbsd.org/faq/index.html (1 of 9)4/29/2009 5:04:22 PM OpenBSD Frequently Asked Questions ● 2.1 - Web Pages ● 2.2 - Mailing Lists ● 2.3 - Manual Pages ● 2.4 - Reporting Bugs 3 - Getting started with OpenBSD ● 3.1 - Buying an OpenBSD CD set ● 3.2 - Buying OpenBSD T-Shirts ● 3.3 - Does OpenBSD provide an ISO image for download? ● 3.4 - Downloading via FTP, HTTP or AFS ● 3.5 - Selecting Hardware ● 3.6 - What is an appropriate "first system" to learn OpenBSD on? 4 - OpenBSD 4.4 Installation Guide ● 4.1 - Overview of the OpenBSD installation procedure. ● 4.2 - Pre-installation checklist ● 4.3 - Creating bootable OpenBSD install media ● 4.4 - Booting OpenBSD install media ● 4.5 - Performing an install ● 4.6 - What files are needed for Installation? ● 4.7 - How much space do I need for an OpenBSD installation? ● 4.8 - Multibooting OpenBSD ● 4.9 - Sending your dmesg to [email protected] after the install ● 4.10 - Adding a file set after install ● 4.11 - What is 'bsd.rd'? ● 4.12 - Common installation problems ● 4.13 - Customizing the install process ● 4.14 - How can I install a number of similar systems? ● 4.15 - How can I get a dmesg(8) to report an install problem? 5 - Building the System from Source ● 5.1 - OpenBSD's Flavors ● 5.2 - Why should I build my system from source? ● 5.3 - Building OpenBSD from source ● 5.4 - Building a release http://www.openbsd.org/faq/index.html (2 of 9)4/29/2009 5:04:22 PM OpenBSD Frequently Asked Questions ● 5.5 - Building X ● 5.6 - Why do I need a custom kernel? ● 5.7 - Building a custom kernel ● 5.8 - Boot-time configuration ● 5.9 - Using config(8) to change your kernel ● 5.10 - Getting more verbose output during boot ● 5.11 - Common Problems when Compiling and Building 6 - Networking ● 6.1 - Before we go any further ● 6.2 - Initial network setup ● 6.3 - How do I filter and firewall with OpenBSD? ● 6.4 - Dynamic Host Configuration Protocol (DHCP) ● 6.5 - Point to Point Protocol ● 6.6 - Tuning networking parameters ● 6.7 - Using NFS ● 6.9 - Setting up a bridge with OpenBSD ● 6.10 - How do I boot using PXE? ● 6.11 - The Common Address Redundancy Protocol (CARP) ● 6.12 - Using OpenNTPD ● 6.13 - What are my wireless networking options? ● 6.14 - How can I do equal-cost multipath routing? 7 - Keyboard and Display Controls ● 7.1 - How do I remap the keyboard? (wscons) ● 7.2 - Is there console mouse support in OpenBSD? ● 7.3 - How do I clear the console each time a user logs out? ● 7.4 - Accessing the console scrollback buffer. (amd64, i386, some Alpha) ● 7.5 - How do I switch consoles? (amd64, i386, Zaurus, some Alpha) ● 7.6 - How can I use a console resolution of 80x50? (amd64, i386, some Alpha) ● 7.7 - How do I use a serial console? ● 7.8 - How do I blank my console? (wscons) ● 7.9 - EVERYTHING I TYPE AT THE LOGIN PROMPT IS IN CAPS! http://www.openbsd.org/faq/index.html (3 of 9)4/29/2009 5:04:22 PM OpenBSD Frequently Asked Questions 8 - General Questions ● 8.1 - I forgot my root password... What do I do! ● 8.2 - X won't start, I get lots of error messages ● 8.3 - Can I use programming language "L" on OpenBSD? ● 8.8 - Is there any way to use my floppy drive if it's not attached during boot? ● 8.9 - OpenBSD Bootloader (i386, amd64 specific) ● 8.10 - Using S/Key on your OpenBSD system ● 8.12 - Does OpenBSD support SMP? ● 8.13 - I sometimes get Input/output error when trying to use my tty devices ● 8.14 - What web browsers are available for OpenBSD? ● 8.15 - How do I use the mg editor? ● 8.16 - Ksh does not appear to read my .profile! ● 8.17 - Why does my /etc/motd file get written over when I modified it? ● 8.20 - Antialiased and TrueType fonts in X ● 8.21 - Does OpenBSD support any journaling filesystems? ● 8.22 - Reverse DNS or Why is it taking so long for me to log in? ● 8.23 - Why do the OpenBSD web pages not conform to HTML4/ XHTML? ● 8.24 - Why is my clock off by twenty-some seconds? ● 8.25 - Why is my clock off by several hours? 9 - Migrating to OpenBSD ● 9.1 - Tips for users of other Unix-like Operating Systems ● 9.2 - Dual boot of Linux and OpenBSD ● 9.3 - Converting your Linux (or other Sixth Edition-style) password file to BSD-style. ● 9.4 - Running Linux binaries on OpenBSD ● 9.5 - Accessing your Linux files from OpenBSD 10 - System Management ● 10.1 - When I try to su to root it says that I'm in the wrong group ● 10.2 - How do I duplicate a filesystem? http://www.openbsd.org/faq/index.html (4 of 9)4/29/2009 5:04:22 PM OpenBSD Frequently Asked Questions ● 10.3 - How do I start daemons with the system? (Overview of rc(8)) ● 10.4 - Why do users get relaying access denied when they are remotely sending mail through my OpenBSD system? ● 10.5 - I've set up POP, but I get errors when accessing my mail through POP. What can I do? ● 10.6 - Why does Sendmail ignore /etc/hosts? ● 10.7 - Setting up a Secure HTTP Server using SSL(8) ● 10.8 - I made changes to /etc/passwd with vi(1), but the changes didn't seem to take place. Why? ● 10.9 - How do I add a user? or delete a user? ● 10.10 - How do I create a ftp-only account? ● 10.11 - Setting up user disk quotas ● 10.12 - Setting up KerberosV Clients and Servers ● 10.13 - Setting up an Anonymous FTP Server ● 10.14 - Confining users to their home directories in ftpd(8). ● 10.15 - Applying patches in OpenBSD. ● 10.16 - Tell me about chroot(2) Apache? ● 10.17 - Can I change the root shell? ● 10.18 - What else can I do with ksh? ● 10.19 - Directory services, in particular YP 11 - The X Window System ● 11.1 - Introduction to X ● 11.2 - Configuring X ● 11.3 - Configuring X on amd64 and i386 ● 11.4 - Starting X ● 11.5 - Customizing X 12 - Hardware and Platform-Specific Questions ● 12.1 - General hardware notes ● 12.2 - DEC Alpha ● 12.3 - AMD 64 ● 12.4 - ARM-based appliances ● 12.5 - HP 9000 series 300, 400 ● 12.6 - HP Precision Architecture (PA-RISC) ● 12.7 - i386 http://www.openbsd.org/faq/index.html (5 of 9)4/29/2009 5:04:22 PM OpenBSD Frequently Asked Questions ● 12.8 - Landisk ● 12.9 - Luna88k ● 12.10 - Mac68k ● 12.11 - MacPPC ● 12.12 - MVME68k ● 12.13 - MVME88k ● 12.14 - SGI ● 12.15 - SPARC ● 12.16 - UltraSPARC ● 12.17 - DEC VAX ● 12.18 - Sharp Zaurus 13 - Multimedia ● 13.1 - How do I configure my audio device? ● 13.2 - Playing different kinds of audio ● 13.3 - How can I play audio CDs in OpenBSD? ● 13.4 - Can I use OpenBSD to record audio samples? ● 13.5 - What can I do if I have audio problems? ● 13.6 - How do I use my MIDI instruments? ● 13.7 - Tell me about Ogg Vorbis and MP3 encoding? ● 13.8 - How can I playback video DVDs in OpenBSD? ● 13.9 - How do I burn CDs and DVDs? ● 13.10 - But I want my media files in format FOO. ● 13.11 - Is it possible to play streaming media under OpenBSD? ● 13.12 - Can I have a Java plugin in my web browser? (i386 & amd64 only) ● 13.13 - Can I have a Flash plugin in my web browser? (i386 only) 14 - Disk Setup ● 14.1 - Using OpenBSD's disklabel(8) ● 14.2 - Using OpenBSD's fdisk(8) ● 14.3 - Adding extra disks in OpenBSD ● 14.4 - How is swap handled? ● 14.5 - Soft Updates ● 14.6 - How does OpenBSD/i386 boot? ● 14.7 - What are the issues regarding large drives with OpenBSD? http://www.openbsd.org/faq/index.html (6 of 9)4/29/2009 5:04:22 PM OpenBSD Frequently Asked Questions ● 14.8 - Installing Bootblocks - i386/amd64 specific ● 14.9 - Preparing for disaster: Backing up and Restoring from tape.
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  • Gigabit Ethernet

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    Ethernet Technologies and Gigabit Ethernet Professor John Gorgone Ethernet8 Copyright 1998, John T. Gorgone, All Rights Reserved 1 Topics • Origins of Ethernet • Ethernet 10 MBS • Fast Ethernet 100 MBS • Gigabit Ethernet 1000 MBS • Comparison Tables • ATM VS Gigabit Ethernet •Ethernet8SummaryCopyright 1998, John T. Gorgone, All Rights Reserved 2 Origins • Original Idea sprang from Abramson’s Aloha Network--University of Hawaii • CSMA/CD Thesis Developed by Robert Metcalfe----(1972) • Experimental Ethernet developed at Xerox Palo Alto Research Center---1973 • Xerox’s Alto Computers -- First Ethernet Ethernet8systemsCopyright 1998, John T. Gorgone, All Rights Reserved 3 DIX STANDARD • Digital, Intel, and Xerox combined to developed the DIX Ethernet Standard • 1980 -- DIX Standard presented to the IEEE • 1980 -- IEEE creates the 802 committee to create acceptable Ethernet Standard Ethernet8 Copyright 1998, John T. Gorgone, All Rights Reserved 4 Ethernet Grows • Open Standard allows Hardware and Software Developers to create numerous products based on Ethernet • Large number of Vendors keeps Prices low and Quality High • Compatibility Problems Rare Ethernet8 Copyright 1998, John T. Gorgone, All Rights Reserved 5 What is Ethernet? • A standard for LANs • The standard covers two layers of the ISO model – Physical layer – Data link layer Ethernet8 Copyright 1998, John T. Gorgone, All Rights Reserved 6 What is Ethernet? • Transmission speed of 10 Mbps • Originally, only baseband • In 1986, broadband was introduced • Half duplex and full duplex technology • Bus topology Ethernet8 Copyright 1998, John T. Gorgone, All Rights Reserved 7 Components of Ethernet • Physical Medium • Medium Access Control • Ethernet Frame Ethernet8 Copyright 1998, John T. Gorgone, All Rights Reserved 8 CableCable DesignationsDesignations 10 BASE T SPEED TRANSMISSION MAX TYPE LENGTH Ethernet8 Copyright 1998, John T.