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OpenBSD Frequently Asked Questions Language: en [teams] de fr nl pl pt Documentation and Frequently Other Documents Asked Questions Upgrade Guide Following -current Commonly Encountered Issues Recent updates Port Testing Guide Using AnonCVS Stable This FAQ is supplemental documentation to the man pages, available both in the installed Using CVSup system and online. The FAQ covers the active release of OpenBSD, currently v3.8. There Manual pages are likely features and changes to features in the development version (-current) of Bug Reporting OpenBSD that are not covered in this FAQ. Mail lists PF User's Guide The FAQ in PDF and plain text form is available in the pub/OpenBSD/doc directory OpenSSH FAQ from the FTP mirrors, along with other documents. PDF files OpenBSD FAQ PF User's Guide 1 - Introduction to OpenBSD Text files ● 1.1 - What is OpenBSD? ● OpenBSD FAQ 1.2 - On what systems does OpenBSD run? ● PF User's Guide 1.3 - Is OpenBSD really free? ● 1.4 - Why might I want to use OpenBSD? ● 1.5 - How can I help support OpenBSD? Back to 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 3.8? ● 1.10 - Can I use OpenBSD as a desktop system? ● 1.11 - Why is/isn't ProductX included? 2 - Other OpenBSD Information Resources ● 2.1 - Web Pages ● 2.2 - Mailing Lists ● 2.3 - Manual Pages ● 2.4 - Reporting Bugs 3 - Obtaining OpenBSD ● 3.1 - Buying an OpenBSD CD set ● 3.2 - Buying OpenBSD T-Shirts ● 3.3 - Does OpenBSD provide an ISO image for download? http://www.openbsd.org/faq/index.html (1 of 7) [19/04/2006 23:03:44] OpenBSD Frequently Asked Questions ● 3.4 - Downloading via FTP, HTTP or AFS ● 3.5 - Obtaining Current Source Code 4 - OpenBSD 3.8 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? ● 4.16 - Upgrading/reinstalling OpenBSD/i386 using bsd.rd-a.out. 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 ● 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 http://www.openbsd.org/faq/index.html (2 of 7) [19/04/2006 23:03:44] OpenBSD Frequently Asked Questions ● 6.13 - What are my wireless networking options? 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) ● 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! 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? ● 8.18 - Why does www.openbsd.org run on Solaris? ● 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 http://www.openbsd.org/faq/index.html (3 of 7) [19/04/2006 23:03:44] OpenBSD Frequently Asked Questions ● 10.2 - How do I duplicate a filesystem? ● 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 file? ● 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() Apache? ● 10.17 - Can I change the root shell? ● 10.18 - What else can I do with ksh? 12 - Platform-Specific Questions ● 12.1 - General hardware notes ● 12.2 - DEC Alpha ● 12.3 - AMD 64 ● 12.4 - CATS ARM development board ● 12.5 - HP 9000 series 300, 400 ● 12.6 - HPPA ● 12.7 - i386 ● 12.8 - Mac68k ● 12.9 - MacPPC ● 12.10 - MVME68k ● 12.11 - MVME88k ● 12.12 - SPARC ● 12.13 - UltraSPARC ● 12.14 - DEC VAX 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 - Tell me about Ogg Vorbis and MP3 encoding? ● 13.6 - How can I playback video DVDs in OpenBSD? ● 13.7 - How do I burn CDs and DVDs? ● 13.8 - But I want my media files in format FOO. ● 13.9 - Is it possible to play streaming media under OpenBSD? ● 13.10 - Can I have Java and/or Flash plugins in my web browser? (i386 only) http://www.openbsd.org/faq/index.html (4 of 7) [19/04/2006 23:03:44] OpenBSD Frequently Asked Questions 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 to swap to a file ● 14.5 - Soft Updates ● 14.6 - How does OpenBSD/i386 boot? ● 14.7 - What are the issues regarding large drives with OpenBSD? ● 14.8 - Installing Bootblocks - i386 specific ● 14.9 - Preparing for disaster: Backing up and Restoring from tape. ● 14.10 - Mounting disk images in OpenBSD ● 14.11 - Help! I'm getting errors with IDE DMA! ● 14.13 - RAID options with OpenBSD ● 14.14 - Why does df(1) tell me I have over 100% of my disk used? ● 14.15 - Recovering partitions after deleting the disklabel ● 14.16 - Can I access data on filesystems other than FFS? ● 14.17 - Can I use a flash memory device with OpenBSD? ● 14.18 - Optimizing disk performance ● 14.19 - Why aren't we using async mounts? 15 - The OpenBSD packages and ports system ● 15.1 - Introduction ● 15.2 - Package management ● 15.3 - Working with ports ● 15.4 - FAQ ● 15.5 - Reporting problems ● 15.6 - Helping us PF User's Guide ● Basic Configuration ❍ Getting Started ❍ Lists and Macros ❍ Tables ❍ Packet Filtering ❍ Network Address Translation ❍ Traffic Redirection (Port Forwarding) ❍ Shortcuts For Creating Rulesets ● Advanced Configuration ❍ Runtime Options ❍ Scrub (Packet Normalization) ❍ Anchors ❍ Packet Queueing and Prioritization ❍ Address Pools and Load Balancing ❍ Packet Tagging (Policy Filtering) ● Additional Topics http://www.openbsd.org/faq/index.html (5 of 7) [19/04/2006 23:03:44] OpenBSD Frequently Asked Questions ❍ Logging ❍ Performance ❍ Issues with FTP ❍ Authpf: User Shell for Authenticating Gateways ❍ Firewall Redundancy with CARP and pfsync ● Example Rulesets ❍ Firewall for Home or Small Office Commonly Encountered Issues ● Common Installation Problems ● How do I upgrade my system? ● Packet Filter ● Should I use Ports or Packages? ● How do I set up a multi-boot system? ● Hard disk DMA errors ● Wireless networking options Recent Updates ● FAQ 8 - Can I use programming language "L" on OpenBSD? - new ● Upgrade Guide - new ● FAQ 15 - Packages and Ports - new ● FAQ 13 - using Java and Flash - new ● FAQ 14 - Can I access data on filesystems other than FFS? - new ● FAQ 14 - Can I use a flash memory device with OpenBSD? - new ● FAQ 13 - Multimedia - new The FAQ maintainers are Nick Holland, Joel Knight, and Steven Mestdagh.
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  • Gigabit Ethernet

    Gigabit Ethernet

    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.