linux/faq/part3_1083581613@rtfm.mit.edu>Expires: 1 Jun 2004 10:49:07 GMTX-Last-Updated: 2001/12/04Organization: noneNewsgroups:comp.os.linux.misc,news.answers,comp.answersSubject: Linux Frequently Asked Questions with Answers (Part 3 of 6)Followup-To: posterFrom:rkiesling@mainmatter.comApproved: news-answers-request@MIT.EDUOriginator: faqserv@penguin-lust.MIT.EDUDate: 11 May 2004 10:51:30 GMTLines: 762NNTP-Posting-Host: penguin-lust.mit.eduX-Trace: 1084272690 senator-bedfellow.mit.edu 574 18.181.0.29Xref: senator-bedfellow.mit.edu comp.os.linux.misc:604743 news.answers:271170 comp.answers:57131ftp://ftp.gnu.org/pub/gnu/parted/. There's also a bootdisk image for resizing root partitions and for running parted onnon-Linux machines. The disk image may be easier for beginners.Building from source could require some extra configuration.Parted also has tutorial-style, plain-text documentation for Linux andFAT (MS-DOS) file systems.Also, some commercial distributions come with their own partitioningsoftware, like Partition Magic.4.5. Is There a Defragmenter for Ext2fs?Yes. There is defrag, a Linux file system defragmenter for ext2,Minix, and old-style ext file systems. It is available atftp://metalab.unc.edu/pub/Linux/system/filesystems/defrag-0.70.tar.gz.Users of the ext2 file system can probably do without defrag, becauseext2 contains extra code to keep fragmentation reduced even in veryfull file systems.4.6. How To Create a File System on a Floppy.To format a 3.5-inch, high density floppy:$ fdformat /dev/fd0H1440$ mkfs -t ext2 -m 0 /dev/fd0H1440 1440For a 5.25 inch floppy, use fd0h1200 and 1200 as appropriate. For theB: drive use fd1 instead of fd0.The -m 0 option tells mkfs.ext2 not to reserve any space on the diskfor the superuser--usually the last 10% is reserved for root.The first command performs a low-level format. The second creates anempty file system. You can mount the floppy like a hard disk partitionand simply cp and mv files, etc.Device naming conventions generally are the same as for other unices.They can be found in Matt Welsh's Installation and Getting Startedguide. Refer to ("Where Is the Documentation?") A more detailed andtechnical description is Linux Allocated Devices by H. Peter Anvin,hpa@zytor.com, which is included in LaTeX and ASCII form in the kernelsource distribution (probably in /usr/src/kernel/Documentation/), asdevices.tex and devices.txt.4.7. Does Linux Support Virtualized File Systems Like RAID?The most recent Linux kernels support software RAID, and they willwork with RAID disk controllers.An automounter for NFS partitions is part of most Linux distributions.In addition, several virtual file system projects exist. One of them,the Linux Logical Volume Manager, is located athttp://linux.msede.com/lvm/.4.8. Does Linux Support File System Encryption?Yes. One file system, ppdd, is archived athttp://pweb.de.uu.net/flexsys.mtk/.4.9. Linux Prints Nasty Messages about Inodes, Blocks, and the Like.You may have a corrupted file system, probably caused by not shuttingLinux down properly before turning off the power or resetting. Youneed to use a recent shutdown program to do this--for example, the oneincluded in the util-linux package, available on sunsite and tsx-11.If you're lucky, the program fsck (or e2fsck or xfsck as appropriateif you don't have the automatic fsck front-end) will be able to repairyour file system. If you're unlucky, the file system is trashed, andyou'll have to re-initialize it with mkfs (or mke2fs, mkxfs, etc.),and restore from a backup.NB: don't try to check a file system that's mounted read/write--thisincludes the root partition, if you don't see   VFS: mounted root ... read-onlyat boot time.4.10. The Swap Area Isn't Working.When you boot (or enable swapping manually) you should see   Adding Swap: NNNNk swap-spaceIf you don't see any messages at all you are probably missing   swapon -av(the command to enable swapping) in your /etc/rc.local or /etc/rc.d/*(the system startup scripts), or have forgotten to make the rightentry in /etc/fstab:   /dev/hda2       none       swap       swfor example.If you see:   Unable to find swap-space signatureyou have forgotten to run mkswap. See the manual page for details; itworks much like mkfs.Running, free in addition to showing free memory, should display:          total       used       freeSwap:        10188       2960       7228If typing "cat /proc/swaps" reveals only file or partition names, butno swap space information, then the swap file or partition needsre-initialization.Use fdisk (as root) to determine which partition on a hard drive hasbeen designated as the swap partition. The partition still needs to beinitialized with mkswap before enabling it with swapon.[Andy Jefferson, Steve Withers]4.11. How To Add Temporary Swap Space.In addition to a swap partition, Linux can also use a swap file. Someprograms, like g++, can use huge amounts of virtual memory, requiringthe temporary creation of extra space. To install an extra 64 MB ofswap space, for example, use the following shell commands:# dd if=/dev/zero of=/swap bs=1024 count=65535# mkswap /swap# swapon /swapThe count= argument to dd determines how big the swap file will be. Inthis example the swap file's name is /swap, but the name and locationare, generally, arbitrary, depending only on the file system'savailable space and your having write permissions in the directory.When you don't need the swap space any more, remove it with thefollowing statements:# swapoff /swap# rm /swapTake a look also at the Installation HOWTO and Installation & GettingStarted for detailed instructions.If that still doesn't provide enough swap space, refer to ("How ToHave More Than 128Mb of Swap.")4.12. How To Remove LILO So the System Boots DOS Again?The lilo program (not the complete LILO package), uses the commandline option -u to uninstall the LILO boot loader. You have to supplythe device name of the device you installed LILO on, for example:   lilo -u /dev/hdaThis rewrites the original, pre-LILO master boot record back to thefirst hard drive, from the boot record saved in /boot/boot.0300. Ifyou installed LILO to a partition as a secondary boot loader, forexample, /dev/hda1, lilo re-installs the original boot sector from thesave file /boot/boot.0301. Refer to the lilo manual page for details.Thanks to Villy Kruse for reminding me to update this answer.If you have an earlier version of LILO, you will have to use the DOS(MS-DOS 5.0 or later, or OS/2) FDISK /MBR (which is not documented).This will restore a standard MS-DOS Master Boot Record. If you haveDR-DOS 6.0, go into FDISK.EXE in the normal way and then select theRe-write Master Boot Record option.If you create a boot floppy during the Windows installation process,make sure that it contains the programs FDISK.EXE, FORMAT.COM, andSYS.COM, and use that to re-install MS-DOS on the hard disk.If you don't have MS-DOS or DR-DOS, you need to have the boot sectorthat LILO saved when you first installed it. You did keep that file,didn't you? It's probably called boot.0301 or some such. Type:   dd if=boot.0301 of=/dev/hda bs=445 count=1(or /dev/sda if you're using a SCSI disk). This may also wipe out yourpartition table, so beware! If you're desperate, you could use   dd if=/dev/zero of=/dev/hda bs=512 count=1This will erase your partition table and boot sector completely: youcan then reformat the disk using your favorite software. But this willrender the contents of your disk inaccessible--you'll lose it allunless you're an expert.Note that the DOS MBR boots whichever (single!) partition is flaggedas "active." You may need to use fdisk to set and clear the activeflags on partitions appropriately.4.13. Why Does fdformat Require Superuser Privileges?The system call to format a floppy can only be done as root,regardless of the permissions of /dev/fd0*. If you want any user to beable to format a floppy, try getting the fdformat2 program. This worksaround the problems by being setuid to root.4.14. The System Checks the Ext2fs Partitions Each Reboot.Refer to ("EXT2-fs: warning: mounting unchecked file system.)4.15. Root File System Is Read-Only.Remount it. If /etc/fstab is correct, you can simply type:   mount -n -o remount /If /etc/fstab is wrong, you must give the device name and possibly thetype, too: e.g.   mount -n -o remount -t ext2 /dev/hda2 /To understand how you got into this state, see, ("EXT2-fs: warning:mounting unchecked file system.")4.16. What Is /proc/kcore?None of the files in /proc are really there--they're all, "pretend,"files made up by the kernel, to give you information about the systemand don't take up any hard disk space./proc/kcore is like an "alias" for the memory in your computer. Itssize is the same as the amount of RAM you have, and if you read it asa file, the kernel does memory reads.4.17. The AHA1542C Doesn't Work with Linux.The option to allow disks with more than 1024 cylinders, which theAHA1542C card can recognize, is only required as a workaround for aPC-compatible BIOS misfeature and should be turned `off' under Linux.For older Linux kernels you need to turn off most of the `advancedBIOS' options--all but the one about scanning the bus for bootabledevices.4.18. Where Is the Journalling File System on the Net?The journalling file system, named Reiserfs has just been releasedfrom testing. It is said to make Linux even faster than Linux with theExt2 file system installed. Complete information is available athttp://devlinux.org/namesys/.5. Porting, Compiling and Obtaining Programs5.1. How To Compile Programs.Most Linux software is written in C and compiled with the GNU Ccompiler. GCC is a part of every Linux distribution. The latestcompiler version, documentation, and patches are onftp://ftp.gnu.org/pub/gnu/.Programs that are written in C++ must be compiled with the GNU G++compiler, which is also included in Linux distributions and availablefrom the same place as GCC.To build version 2.0.x kernels, you will need GCC version 2.7.2.x,approximately. Trying to build an early Linux kernel with a differentcompiler, like GCC 2.8.x, EGCS, or PGCC, may cause problems because ofGCC related code dependencies. Kernel versions 2.3 and 2.4 shouldcompile correctly with more recent compilers.Information on the EGCS compiler is athttp://www.gnu.org/software/gcc/gcc.html.Note that at this time, the kernel developers are not answering bugrequests for earlier kernels, but instead are concentrating ondeveloping 2.4.x version kernels and maintaining 2.2.x versionkernels.[J.H.M. Dassen, Axel Boldt]5.2. How To Install GNU Software.On a correctly configured system, installing a GNU software packagerequires four steps:  * With the source.tar.gz archive in the /usr/src/ directory, or    wherever you maintain your source files, untar and decompress the    package with the command:    tar zxvf package-name.tar.gz  * Run the ./configure script in the untarred source archive's    top-level directory with whatever command line arguments you need.    The options that configure recognizes are usually contained in a    file called INSTALL or README.  * Run make. This will build the source code into an executable    program (or programs) and may take a few minutes or a few hours,    depending on the speed of the computer and the size of the    package.  * Run make install. This will install the compiled binaries,    configuration files, and any libraries in the appropriate    directories.5.3. Where To Get Java.The Sun Microsystems Java runtime environments and developer's kitsare at http://java.sun.com/java/.You can also get the source code, which is licensed by SunMicrosystems.The home page of IBM's Jikes Java compiler ishttp://www10.software.ibm.com/developerworks/opensource/jikes.There is a version of Sun's HotJava browser for Linux at:http://www.java.sun.com/products/hotjava/.Kaffee, a free Java clone, is available from:http://www.kaffe.org/.There is a resource page of free and commercial Java packages at:http://www.blackdown.org/java-linux.html.Netscape Communicator comes with its own version of the Java RuntimeEnvironment, so if you need Java only to view Web graphics, you mayalready have the runtime version of the Java Virtual Machine andlibraries that you need installed on your system. You can downloadCommunicator fromhttp://www.netscape.com/.5.4. How To Port XXX to Linux.In general, *nix programs need very little porting. Simply follow theinstallation instructions. If you don't know--and don't know how tofind out--the answers to some of the questions asked during theinstallation procedure, you can guess, but this tends to produce buggyprograms. In this case, you're probably better off asking someone elseto do the port. If you have a BSD-ish program, you should try using-I/usr/include/bsd and -lbsd on the appropriate parts of thecompilation lines.5.5. What Is ld.so and How To Get It?ld.so is the dynamic library loader. Each binary using sharedlibraries used to have about 3K of start-up code to find and load theshared libraries. Now that code has been put in a special sharedlibrary, /lib/ld.so, where all binaries can look for it, so that itwastes less disk space, and can be upgraded more easily. ld.so can beobtained from http://tsx-11.mit.edu/pub/linux/packages/GCC/ and mirrorsites. The latest version at the time of writing isld.so.1.9.5.tar.gz. /lib/ld-linux.so.1 is the same thing for ELF("What's all this about ELF? ") and comes in the same package as thea.out loader.5.6. How To Upgrade the Libraries without Trashing the System.WarningNote: You should always have a rescue disk set ready when you performthis procedure, in the likely event that something goes wrong!This procedure is especially difficult if you're upgrading very oldlibraries like libc4. But you should be able to keep libc4 on the samesystem with libc5 libraries for the programs that still need them. Thesame holds true for upgrading from libc5 to the newer-yet glibc2libraries.The problem with upgrading dynamic libraries is that, the moment youremove the old libraries, the utilities that you need to upgrade tothe new version of the libraries don't work. There are ways aroundaround this. One is to temporarily place a spare copy of the run timelibraries, which are in /lib/, in /usr/lib/, or /usr/local/lib/, oranother directory that is listed in the /etc/ld.so.conf file.For example, when upgrading libc5 libraries, the files in /lib/ mightlook something like:libc.so.5libc.so.5.4.33libm.so.5libm.so.5.0.9These are the C libraries and the math libraries. Copy them to anotherdirectory that is listed in /etc/ld.so.conf, like /usr/lib/:$ cp -df /lib/libc.so.5* /usr/lib/$ cp -df /lib/libm.so.5* /usr/lib/$ ldconfigBe sure to run ldconfig to upgrade the library configuration.The files libc.so.5 and libm.so.5 are symbolic links to the actuallibrary files. When you upgrade, the new links will not be created ifthe old links are still there, unless you use the -f flag with cp. The-d flag to cp will copy the symbolic link itself, and not the file itpoints to.If you need to overwrite the link to the library directly, use the -fflag with ln.For example, to copy new libraries over the old ones, try this. Make asymbolic link to the new libraries first, then copy both the librariesand the links to /lib/, with the following commands.$ ln -sf ./libm.so.5.0.48 libm.so.5$ ln -sf ./libc.so.5.0.48 libc.so.5$ cp -df libm.so.5* /lib$ cp -df libc.so.5* /libAgain, remember to run ldconfig after you copy the libraries.If you are satisfied that everything is working correctly, you canremove the temporary copies of the old libraries from /usr/lib/ orwherever you copied them.5.7. How To Use Code or a Compiler Compiled for a 486 on a 386.Yes, unless it's the kernel.The -m486 option to GCC, which is used to compile binaries for x486machines, merely changes certain optimizations. This makes forslightly larger binaries that run somewhat faster on a 486. They stillwork fine on a 386, though, with a small performance hit.However, from version 1.3.35 the kernel uses 486 or Pentium-specificinstructions if configured for a 486 or Pentium, thus making itunusable on a 386.GCC can be configured for a 386 or 486; the only difference is thatconfiguring it for a 386 makes -m386 the default and configuring for a486 makes -m486 the default. In either case, these can be overriddenon a per-compilation basis or by editing /usr/lib/gcc-lib/i*-linux/n.n.n/specs.There is an alpha version of GCC that knows how to do optimizationwell for the 586, but it is quite unreliable, especially at highoptimization settings. The Pentium GCC can be found onftp://tsx-11.mit.edu/pub/linux/ALPHA/pentium-gcc/. The ordinary 486GCC supposedly produces better code for the Pentium using the -m386,or at least slightly smaller.5.8. What Does "gcc -O6" Do?Currently, the same as -O2 (GCC 2.5) or -O3 (GCC 2.6, 2.7). Any numbergreater than that does the same thing. The Makefiles of newer kernelsuse -O2, and you should probably do the same.5.9. Where Are linux/*.h and asm/*.h?The files /usr/include/linux/ and /usr/include/asm/ are often softlinks to the directories where the kernel headers are. They areusually under /usr/src/kernel*/.If you don't have the kernel sources, download them. Refer to theanswer: ("How To Upgrade/Recompile a Kernel.")Then, use rm to remove any garbage, and ln to create the links:$ rm -rf /usr/include/linux /usr/include/asm$ ln -sf /usr/src/linux/include/linux /usr/include/linux$ ln -sf /usr/src/linux/include/asm-<architecture> /usr/include/asmThe assembly language files reside in architecture-specificdirectories, so you need to link /usr/src/include/asm to/usr/src/linux/include/asm-i386 on PC compatible systems, to/usr/src/linux/include/asm-sparc on Sun Sparc systems, to/usr/src/linux/include/asm-ppc on PPC systems, and so on.You'll also find that you may need to do `make config' as in anewly-unpacked kernel source tree, to create linux/autoconf.h.5.10. What To Do about Errors Trying to Compile the Kernel.See the previous question regarding the header files.Remember that when you apply a patch to the kernel, you must use the"-p0" or "-p1" option: otherwise, the patch may be misapplied. See thepatch manual page for details."ld: unrecognized option `-qmagic'" means that you should get a newerlinker, fromftp://tsx-11.mit.edu/pub/linux/packages/GCC/, in the filebinutils-2.8.1.0.1.bin.tar.gz.5.11. How To Make a Shared Library.For ELF,$ gcc -fPIC -c *.c$ gcc -shared -Wl,-soname,libfoo.so.1 -o libfoo.so.1.0 *.oFor a.out, get tools-n.nn.tar.gz fromtsx-11.mit.edu/pub/linux/packages/GCC/src/. It comes withdocumentation that will tell you what to do. Note that a.out sharedlibraries are a very tricky business. Consider upgrading yourlibraries to ELF shared libraries. See the ELF HOWTO, atftp://metalab.unc.edu/pub/Linux/docs/HOWTO/5.12. Programs Are Very Large.With an ELF compiler ("What's All This about ELF? glibc?"), the mostcommon cause of large executables is the lack of an appropriate .solibrary link for one of the libraries you're using. There should be alink like libc.so for every library like libc.so.5.2.18.With an a.out compiler the most common cause of large executables isthe -g linker (compiler) flag. This produces (as well as debugginginformation in the output file) a program which is staticallylinked--one which includes a copy of the C library instead of adynamically linked copy.Other things worth investigating are -O and -O2, which enableoptimization (check the GCC documentation), and -s (or the stripcommand) which strip the symbol information from the resulting binary(making debugging totally impossible).You may wish to use -N on very small executables (less than 8K withthe -N), but you shouldn't do this unless you understand itsperformance implications, and definitely never with daemons.5.13. Does Linux Support Threads or Lightweight Processes?As well as the Unix multiprocessing model involving heavyweightprocesses, which is of course part of the standard Linux kernel, thereare several implementations of lightweight processes or threads.Recent kernels implement a thread model, kthreads. In addition, thereare the following packages available for Linux.  * GNU glibc2 for Linux has optional support for threads. The archive    is available from the same place as glibc2,ftp://ftp.gnu.org/pub/gnu/  * In ftp://sipb.mit.edu/pub/pthread/ or    ftp://ftp.ibp.fr/pub/unix/threads/. Documentation isn't in the    package, but is available on the World Wide Web athttp://www.mit.edu:8001/people/proven/home_page.html. Newer Linux    libc's contain the pthreads source. The GNU Ada compiler onftp://metalab.unc.edu/pub/Linux/devel/lang/ada/gnat-3.01-linux+elf    .tar.gz contains binaries made from that source code.  * Inftp://ftp.cs.washington.edu:/pub/qt-001.tar.Z is QuickThreads.    More information can be found in the technical report, available    on the same site is /tr/1993/05/UW-CSE-93-05-06.PS.Z.  * In gummo.doc.ic.ac.uk/rex/ is lwp, a very minimal implementation.  * In ftp://ftp.cs.fsu.edu:/pub/PART/, an Ada implementation. This is    useful mainly because it has a lot of Postscript papers that    you'll find useful in learning more about threads. This is not    directly usable under Linux.    Please contact the authors of the packages in question for details.5.14. Where To Find lint for Linux.Roughly equivalent functionality is built into GCC. Use the -Walloption to turn on most of the useful extra warnings. See the GCCmanual for more details (type F1-i in Emacs and select the entry forGCC).There is a freely available program called lclint that does much thesame thing as traditional lint. The announcement and source code areavailable at on ftp://larch.lcs.mit.edu/pub/Larch/lclint/; on theWorld Wide Web, look athttp://lclint.cs.virginia.edu/.5.15. Where To Find Kermit for Linux.Kermit is distributed under a non-GPL copyright that makes its termsof distribution somewhat different. The sources and some binaries areavailable onftp://kermit.columbia.edu.The WWW Home Page of the Columbia University Kermit project ishttp://www.columbia.edu/kermit/.5.16. How To Use Linux with a Cable Modem.The www.CablemodemInfo.com and xDSL Web page athttp://www.cablemodeminfo.com/ has a section devoted to Linux.5.17. Is There an ICQ Program That Runs under Linux?Several ICQ clients are available on metalab.unc.edu. (Refer to:"Where Are the Linux FTP Archives?") ICQ itself does not have a Linuxclient, but there is a Java client athttp://www.mirabilis.com/download/.6. Solutions to Common Miscellaneous Problems6.1. FTP Transfers Seem to Hang.FTP transfers that die suddenly are due, apparently, to some form ofoverrunning buffer. It occurs both with Linux and Microsoft servers.On Linux systems, The problem seems to occur most commonly with thedistribution's server software.If you receive ftp: connection refused errors, then the problem islikely due to a lack of authentication. Refer to "FTP or Telnet ServerWon't Allow Logins.."One remedy is to be replacing the distribution FTP server with theLinux port of the OpenBSD FTP server. The home page is:http://www.eleves.ens.fr:8080/home/madore/programs/To install the BSD server, follow the installation instructions, andrefer to the manual pages for inetd and inetd.conf. (If you have thenewer xinetd, see below.) Be sure to tell inetd to run the BSD daemonalone, not as a subprocess of, for example, tcpd. Comment out the linethat begins "ftp" in the /etc/inetd.conf file and replace it with aline similar to (if you install the new ftpd in /usr/local/sbin/):# Original entry, commented out.#ftp    stream  tcp     nowait  root    /usr/sbin/tcpd /usr/sbin/in.ftpd# Replacement entry:ftp     stream  tcp     nowait  root    /usr/local/sbin/ftpd -lThe replacement daemon will become effective after rebooting orsending (as root) a SIGHUP to inetd, e.g.:# kill -HUP inetdTo configure xinetd, create an entry in /etc/xinetd.d per theinstructions in the xinetd.conf manual page. Make sure, again, thatthe command-line arguments for ftpd are correct, and that you haveinstalled the /etc/ftpusers and /etc/pam.d/ftp files. Then restartxinetd with the command: /etc/rc.d/init.d/xinetd restart. The commandshould report "OK," and the restart will be noted in the systemmessage log.6.2. Free Dumps Core.In Linux 1.3.57 and later, the format of /proc/meminfo was changed ina way that the implementation of free doesn't understand. Get thelatest version, from metalab.unc.edu, in/pub/Linux/system/Status/ps/procps-0.99.tgz.6.3. Netscape Crashes Frequently.Netscape shouldn't crash, if it and the network are properlyconfigured. Some things to check:  * Make sure that the MOZILLA_HOME environment variable is correctly    set. If you installed Netscape under /usr/local/netscape/, for    example, that should be the value of MOZILLA_HOME. Set it from the    command line (e.g, "export MOZILLA_HOME="/usr/local/netscape""    under bash or add it to one your personal or system initialization    files. Refer to the manual page for your shell for details.  * If you have a brand-new version of Netscape, try a previous    version, in case the run-time libraries are slightly incompatible.    For example, if Netscape version 4.75 is installed (type "netscape    --version" at the shell prompt), try installing version 4.7. All    versions are archived atftp://ftp.netscape.com/.  * Netscape uses its own Motif and Java Runtime Environment    libraries. If a separate version of either is installed on your    system, ensure that they aren't interfering with Netscape's    libraries; e.g., by un-installing them.  * Make sure that Netscape can connect to its default name servers.    The program will appear to freeze and time out after several    minutes if it can't. This indicates a problem with the system's    Internet connection; likely, the system can't connect to other    sites, either.6.4. FTP or Telnet Server Won't Allow Logins.This applies to server daemons that respond to clients, but don'tallow logins. On new systems that have Pluggable AuthenticationModules installed, look for a file named, "ftp," or "telnet," in thedirectory /etc/pam/ or /etc/pam.d/. If the correspondingauthentication file doesn't exist, the instructions for configuringFTP and Telnet authentication and other PAM configuration, should bein /usr/doc/pam-<version>. Refer also to the answer for "FTP serversays: "421 service not available, remote server has closedconnection."."If it's an FTP server on an older system, make sure that the accountexists in /etc/passwd, especially "anonymous."This type of problem may also be caused a failure to resolve the hostaddresses properly, especially if using Reverse Address ResolutionProtocol (RARP). The simple answer to this is to list all relevanthost names and IP addresses in the /etc/hosts files on each machine. (Refer to the example /etc/hosts and /etc/resolv.conf files in:"Sendmail Pauses for Up to a Minute at Each Command..") If the networkhas an internal DNS, make sure that each host can resolve networkaddresses using it.If the host machine doesn't respond to FTP or Telnet clients at all,then the server daemon is not installed correctly, or at all. Refer tothe manual pages: inetd and inetd.conf on older systems, or xinetd andxinetd.conf, as well as ftpd, and telnetd.6.5. How To Keep Track of Bookmarks in Netscape?This probably applies to most other browsers, too. In thePreferences/Navigator menu, set your home page to Netscape'sbookmarks.html file, which is located in the .netscape (with a leadingperiod) subdirectory. For example, if your login name is "smith," setthe home page to:   file://home/smith/.netscape/bookmarks.htmlSetting up your personal home page like this will present you with anicely formatted (albeit possibly long) page of bookmarks whenNetscape starts. And the file is automatically updated whenever youadd, delete, or visit a bookmarked site.