─^≥&╞GS v≡WΦ%â─╕£$ P v≡WΦâ─â~t)Ä∞9&â>^uÄε9&â>`t╕ó$δ6╕º$δ1É╕¼$δ+ÉÄ≡9&÷▓t╕▒$ P v≡WΦ╠â─Ä≡9&÷│Çu╕╢$ P v≡WΦ▒â─╕╗$ P v≡WΦóâ─Ä≥9&â>Σ └≈╪¿t+╕ùÄ└&ÇΣ â~u:&íΣ ╣ùÄ┘#εëFΣ¿t╛δ&É╕ùÄ└δ┘É÷FΣt╛δÉïv■¿t
╛δ&ï6Σ â■└≈╪¿ t ╕╛$δ`É â~t6≈╞t╕├$ P v≡WΦâ─≈╞t╕╚$ P v≡WΦ√â─ï╞¿t3╕═$δ"É≈╞t╕╥$δÉ≈╞t╕╫$δ
Éï╞¿t╕▄$ P v≡WΦ┬â─Ä≡9&÷│Çtâ~tÄ⌠9&â>zu╕ß$ P v≡WΦòâ─╕µ$ P v≡WΦåâ─╕ε$ P v≡WΦwâ─╕≤$ P v≡WΦhâ─Ä÷9&â>j uÄΓ9&─ X&ïç╝&ïù╛δ╕⌡$î┌ëFⁿëV■RPÄ°9& 6⌠Ä·9& 6≥╕÷$ P╕P╕% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦⁿâ─╕% P v≡WΦφâ─Äⁿ9& 6║& 6╕Ä■9& 6╛& 6╝Ä:& 6╢& 6┤╕#% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦBâ─Ä:& 6╞& 6─Ä:& 6╩& 6╚Ä:& 6┬& 6└╕0% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦ⌡â─╕=% P v≡WΦDâ─Ä:&í&&ï(Ç─0ü╥T|RP╕E% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦ â─ v≡WÜ" α â─ï≡Äα9&á£$■P░PÜ╢] â─╟FΩ╕pPÜ╒ â─ëF÷ëV°ëv∞ë~εïv≥ v∞╕O% P v⌠VÜαα â─
─^≥&╞GS v≡WΦ%â─╕£$ P v≡WΦâ─â~t)Ä∞9&â>^uÄε9&â>`t╕ó$δ6╕º$δ1É╕¼$δ+ÉÄ≡9&÷▓t╕▒$ P v≡WΦ╠â─Ä≡9&÷│Çu╕╢$ P v≡WΦ▒â─╕╗$ P v≡WΦóâ─Ä≥9&â>Σ └≈╪¿t+╕ùÄ└&ÇΣ â~u:&íΣ ╣ùÄ┘#εëFΣ¿t╛δ&É╕ùÄ└δ┘É÷FΣt╛δÉïv■¿t
╛δ&ï6Σ â■└≈╪¿ t ╕╛$δ`É â~t6≈╞t╕├$ P v≡WΦâ─≈╞t╕╚$ P v≡WΦ√â─ï╞¿t3╕═$δ"É≈╞t╕╥$δÉ≈╞t╕╫$δ
Éï╞¿t╕▄$ P v≡WΦ┬â─Ä≡9&÷│Çtâ~tÄ⌠9&â>zu╕ß$ P v≡WΦòâ─╕µ$ P v≡WΦåâ─╕ε$ P v≡WΦwâ─╕≤$ P v≡WΦhâ─Ä÷9&â>j uÄΓ9&─ X&ïç╝&ïù╛δ╕⌡$î┌ëFⁿëV■RPÄ°9& 6⌠Ä·9& 6≥╕÷$ P╕P╕% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦⁿâ─╕% P v≡WΦφâ─Äⁿ9& 6║& 6╕Ä■9& 6╛& 6╝Ä:& 6╢& 6┤╕#% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦBâ─Ä:& 6╞& 6─Ä:& 6╩& 6╚Ä:& 6┬& 6└╕0% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦ⌡â─╕=% P v≡WΦDâ─Ä:&í&&ï(Ç─0ü╥T|RP╕E% P v⌠ v≥Üαα â─ v⌠ v≥ v≡WΦ â─ v≡WÜ" α â─ï≡Äα9&á£$■P░PÜ╢] â─╟FΩ╕pPÜ╒ â─ëF÷ëV°ëv∞ë~εïv≥ v∞╕O% P v⌠VÜαα â─
■+└&ëG&ëë╛n Ä┌9&9ptHÄ▄9&9vt=╕PPÄ▐9& 6û& 6öÜ`┘â─╕æ% PÄ▐9& 6û& 6öÜZ┘â─ÜT┘δ╕╡% PÜ|α â─╗TÄ :ë₧■îå■&╟╕╨PÜ╒ â─ëF∞ëVε╕pPÜ╒ â─ëF≡ëV≥+└ëF÷ëF⌠èå{ ■å{ <vΘvâ~uZ 6`# 6^#╕└% P ╢~ VÜαα â─ ╕P ╢~ VÜ" α â─P ╢~ VÜJ] ow you to NFS export the Novell network drives. It hasπ caveats in that it will not perform as well as directly mountingπ the Novell fileserver, that it requires another machine, and that itπ will generate roughly twice as much network traffic, but it will work.ππ Stan's Own Server (NFS server).ππ spdcc.com:pub/sos/soss.zooπ spdcc.com:pub/sos/sossexe.zooππ A version "couple of bugs fixed: IP numbers and subdirectoriesπ with extensions)" is available from:π hilbert.wharton.upenn.edu:/pub/tcpip/soss.zipππ QUESTION: Files get corrupted when using NFS over wider area networksπ or SLIP, why ? How do I stop it ?ππ ANSWER: Certain vendors (Sun primarily) shipped many machines runningπ NFS without UDP checksums. Great on ethernet, suicide otherwise. UDPπ checksums can be enabled on most file servers. Linux has it enabled byπ default from pl13 onwards - but both ends need to have it enabled...ππ QUESTION: Why are my NFS files all read only ?ππ ANSWER: The Linux NFS server defaults to read only. RTFM the 'exports'π and nfsd manual pages. With non Linux servers you may also need toπ alter /etc/exports ππ QUESTION: I mount from a linux nfs server and while ls works I can'tπ read or write files. How do I fix this ? ππ ANSWER: You must mount a Linux filestore with rsize=1024,wsize=1024π (or 2048 if you really want - 1024 is a better choice).ππ QUESTION: I mount from a linux nfs server with a blocksize of betweenπ 3500-4000 and it crashes the Linux box regularly, why ?ππ ANSWER: This is a known problem that is being worked on, refer toπ previous question. Don't you hate answers like that ? :)ππ QUESTION: Can Linux do NFS over TCP ?ππ ANSWER: No. To do this would require someone to spend the time toπ update the rpc code to add rpc stream record marking. It should workπ then.ππ QUESTION: Why do I get loads of strange errors trying to mount aπ machine from a Linux box. ππ ANSWER: This is possibly related to a restriction imposed by olderπ NFS servers. Make sure your users are in 8 groups or less.ππ QUESTION: Why are my Linux NFS clients very slow when writing to Sunπ & BSD systems ?ππ ANSWER: NFS writes are normally synchronous, meaning that all file-π -system changes occur in the order they transmitted, this means thatπ if before NFS will allow you to write any more data, any previousπ write must have already completed, (you can disable this if you don'tπ mind risking losing data). Worse still, BSD derived kernels, thisπ includes Sun systems, tend to be unable to work in small blocks. Thusπ when you write 4K of data from a Linux box in the 1K packets it uses,π BSD does this:ππ read 4K pageπ alter 1Kπ write 4K back to physical diskπ read 4K pageπ alter 1Kπ write 4K page back to physical diskπ etc..π π Better systems don't have this problem. The Linux client is howeverπ quite slow anyway.ππ QUESTION: I've heard NFS is not secure is this true ?ππ ANSWER: Yes, totally. Running NFS in an uncontrolled environment isπ rather like leaving your front door open, painting 'On holiday' onπ your house and posting maps to every known criminal...π In a fairly secure environment or when you can recover data from stupidπ misuse its pretty much OK. The worst someone can easily do is alter allπ the files on an NFS mounted disk, and/or crash the machine. So long asπ you don't mount your system files writable you should be mostly safe.ππ QUESTION: I occasionally mount from lots of different places, do I haveπ to mount them all each time I boot ?ππ ANSWER: No you can use the automounter to mount disks as you accessπ them.ππ QUESTION: How do I stop things hanging when a server goes down ?ππ ANSWER: There are three main NFS behaviours:ππ soft: Your NFS client will report an error to the processπ concerned if an NFS server doesn't answer after a fewπ retries. Most software handles this well - but not all.π π hard: Your NFS client will try forever unless killed off.π Operations will be restarted when the NFS serverπ recovers or reboots.π π hard,intr: As hard but ^C will also stop the NFS retrying. Inπ a few cases, notably nfs mounted /usr/spool/mail disks,π this doesn't help as the shell will be ignoring ^C whenπ it checks you have mail.ππ If you intend to leave your machine unattended, then choosing theπ 'soft' option is probably best, because while it might cause someπ problems to an application running, it won't halt your whole machineπ if a server that it is attached to goes down. If your machine willπ always have a human operator available, then the 'hard,intr' optionπ might be best. The hard option would be best suited to you if you canπ afford to wait, and don't want the process writing to the serverπ interrupted at all.ππ QUESTION: Can I use two slip interfaces ?ππ ANSWER: Yes. If you have, for example, three machines which youπ would like to interconnect, then you most certainly could useπ two slip interfaces on one machine and connect each of the otherπ machines to it. Simply configure the second interface as you didπ the first. NOTE that the second interface will require a differentπ IP address to the first. You may need to play with the routing aπ bit to get it to do what you want, but it should work.ππ10. Known bugs.ππ There are several known bugs with the NET-2 software. Note that theseπ may or may not be fixed with a newer version of the NET-2 code;π therefore, I leave them here. π π The bugs here are for NET-2d, found in kernels 0.99.pl10, pl11, π and pl12, and pl13, and pl14. NET-2e (currently in Beta), whenπ released, may or may not have fixed these bugs. ππ * Bug with route guessing code. If you ifconfig the "lo"π interface before the "eth0" interface in rc.inet1, whenever youπ add a route, it will be added to "lo" instead of "eth0". π (Simply use the "route" command by itself; it will display allπ of your routes. If your "default" route, which should be outπ on the ethernet, is for device "lo" instead of "eth0", then you'reπ seeing this bug.) π π This is just a problem with the route guessing code. Severalπ things can fix it: 1) ifconfig/route on "eth0" before "lo" inπ rc.inet1; or, 2) Set your netmask to 255.0.0.0 (which is reportedπ to work, but I can't guarantee it). This should be fixed in NET-2e.ππ * Missing IP packet fragmentation. Packet fragmentation allows theπ various protocol layers to "chop up" packets into smaller packetsπ if the MTU (maximum tranfer unit) of one network differs fromπ another. NET-2e should contain packet fragmentation/defragmentationπ code, but NET-2d currently does not.π This now only applies to kernel earlier than pl14+, as it is nowπ supported.ππ * Weak NFS support. There have been a number of success stories withπ NFS under Linux, however, not all of the support is there. Forπ one thing, the current NFS buffer size is much smaller, and π therefore much slower, than other implementations of NFS.ππ11. Copyright Message. (We're not ogres, nor are we silly).ππ The NET-2-HOWTO is copyright by Terry Dawson and Matt Welsh. A verbatimπ copy of this document may be reproduced and distributed in any medium,π physical or electronic without permission of the authors. Translationsπ are similarly permitted without express permission if such translationsπ include a notice stating who performed the translation, and that it isπ a translation. Commercial redistribution is allowed and encouraged,π however, the authors would like to be notified of any suchπ distributions. ππ Short quotes may be used without prior consent by the authors.π Derivative works and partial distributions of the NET-2-HOWTO mustπ include either a verbatim copy of this file, or make a verbatim copyπ of this file available. If the latter is the case, a pointer to theπ verbatim copy must be stated at a clearly visible place.ππ In short, we wish to promote dissemination of this information throughπ as many channels as possible. However, we wish to retain copyright onπ this HOWTO document, and would like to be notified of any plans toπ redistribute it. Further we desire that ALL information provided inπ this HOWTO be disseminated.ππ If you have any questions relating to the conditions of this copyright,π please contact Matt Welsh, the Linux HOWTO coordinator, at:π mdw@sunsite.unc.edu, or +1 607 256 7372.πππ12. Miscellaneous.ππ I'm sure that I've missed something. This NET-2 HOWTO was thrown π together with the help of Matt Welsh, and Jeff Uphoff. Other majorπ contributors have been Alan Cox, Fred van Kempen, and others justπ like yourself. Hopefully it will help you, and others out there, getπ networking under Linux. ππ Future plans for the NET-2 HOWTO include a section on setting upπ your own Linux LAN (with SLIP and/or Ethernet), adventures inπ routing, and the use of netstat and other network administrationπ under Linux. For now, the information here should be more than π enough. :)π π If you have questions about setting up NET-2, feel free to mail me, or π if you have any corrections, additions, or errata for this NET-2 HOWTO, π send me any and all changes (cdiffs are nice, but I'm flexible). ππ Of course, thanks to Fred, Linus, Ross, Phil, Paul, Don, Alan,π Matt, and everyone else who helped to develop the NET-2 code and workπ on previous versions of TCP/IP for Linux and the NET-FAQ. Finally,π Linux has a complete implementation of TCP/IP. It may not be forπ everyone yet. But for those who have an itch they want to scratch,π happy hacking, here it is.ππ Cheers,ππ Terry Dawson, (terryd@extro.ucc.su.oz.au)ππ13. Change History.ππ Changes from 1.8:π correction to broadcast address calculation, thanks Andr'as Salamonπ tcp/ip tutorials added thanks to Gilbert Callaghanπ These annotations at the suggestion of Andy Burgessπ Shadow password section updated - thanks Rick Sladkeyπ added Slip Server section - thanks Fredπ added /etc/net/diphosts section - thanks Fredπ enhanced the netmask description a littleπ Revamped for 0.99.14π Added Indexππ Changes from 1.9:π Added change history.π Corrected Archive header now that I understand what it is there forπ Thanks to _everyone_ who helped me understand :)π Ammended loopback route details - thanks Jeffrey A. Kintscher.π First attempt at enlarging the configuration section to cope withπ different networks and different distributions thanksπ Eric Christensen.π Reinstated /dev/arp as a required device. Oops.π Finally added resolv+(8) man page reference.π Tried to clean the slip section a bit.π Added leased line/cable slip link config using slattach.π Corrected a minor PLIP stoopidity I inflicted that fortunately nooneπ appears to have noticed.π Ammended Slip Server config to run a script in lieu of 'dip -i'π Fixed numerous tyops and mizpellinks (When will I not ?)ππ
