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ip question

Tue, 18 Jul 2000 14:24:30 -0700
From: Don Marti, Linux Gazette Asst. Editor (gazette@ssc.com)

On Tue, Jul 18, 2000, James Strong wrote:

In studying ip addressing I come across the reference of 255 and 256.
if all ones (11111111) = ?
if all 0s (00000000) = ?

How does one come up with 256 sometime and 255 other times?

-confused

There are no "256"s in valid IP addresses.

IP addresses are 32 bits, and are written in 4 octets of 8-bit numbers expressed in decimal form. The biggest possible 8-bit number is 255, which is 2^7 + 2^6 + ... + 2^1 + 2^0.

A good explanation of IP addresses is in the Linux Network Administrator's Guide, available in your favorite Linux distribution or from linuxdoc.org.

-- Don Marti


LILO

Wed, 28 Jun 2000 03:05:22 ADT
From: Heather Stern, Linux Gazette Technical Editor (linux-questions-only@ssc.com)

Mathieu (blackened69@hotmail.com) wrote:

Hi, I had a problem with LILO, everytimes I've install Redhat 6.2 on this hhd it did the same problem... My hdd partition has 2055 cylenders and when I boot up the computer, it just prints "LI"... Have any idear?

- Mathieu

[ This is the number one problem with LILO - it's a bit sensitive to some matters of size and cylinder location. Matthieu here isn't the only one who's had this question, it comes up several times every month, and has been in the FAQ for a while. The number two problem is the same with some number speewing at you.

Either usually means there is a geometry problem, and the right options can be added to lilo.conf with any text editor. See LILO's own docs (usually in /usr/doc/packages/lilo). Somewhat more usefully, the LILO Mini-Howto was just updated a few days ago: http://www.linuxdoc.org/HOWTO/mini/LILO.html

I think you readers will also be pleased to know there are numerous alternatives. You can find a stack of them by going to freshmeat.net and typing "boot loader" or "bootloader" into its search box. (Do both seperately, you get different lists.) Ones worth highlighting are GRUB, Smart Boot Manager, GAG (it may be a slow link, but it looks really nice) and Winux (an odd one... it's a configurator for using LOADLIN effectively). They don't seem to mention Debian's 'mbr' - which (like Smart Boot Manager) is only a first stage (you still need LILO or something like it to chain into the kernel) but even less verbose than FreeBSD's spartan partition picker. You have to press SHIFT if you care to change which partition to boot from.

Lastly, if after you install LILO, Windows/DOS won't boot even from a floppy, boot from a rescue disk and use Linux fdisk to change your extended partition type to 85 (linux extend). This will stop it from looking for a D: that simply isn't there.

--Heather.]


POP3 Login Problem... solved

Wed, 5 Jul 2000 14:54:26 -0400
From: Steve Lobo (steve@caboco.com)

I love your columns - very informative and very helpful.

I've searched high and low for a solution to this problem but haven't had any luck.

I recently re-installed RH6.0 (after root was compromised by a non-malicious hacker), and haven't done updated anything (yet) except my version of XWindows.

Everything is more or less working, but I'm having difficulty logging into my POP3 server. I have a perfectly valid and functioning user account, but POP3 is rejecting my login (with the Linux account's password) with a "-ERR Bad login" message.

Are there any circumstances where my POP3 server would be looking for a different password than the OS? Or is there something else that could be going on?

Thanks in advance for your assistance!

-Steve Lobo

But Steve found his answer and sent it in:

Nevermind! Not sure why, but the pop file didn't exist in /etc/pam.d - so although everything looked to be in order in terms of connecting to port 110 attempting to get into a transaction state, POP had no idea about how to authenticate. I just rebuilt imap* from my RH CDRoms and everything's fine...

Thanks anyway!


Addendum to Tech FAQ 4 ("Where do I find help")

Mon, 17 Jul 2000 06:09:27 +0200
From: "Mechelynck Antoine" (tonymec@belgacom.net)

If you prefer reading HTML to plain text, the KDE help system (program kdehelp) provides a nice interface to man pages (But of course it's supposed to be used under the kdm display manager, not on a "dumb" console.) Either type "man:<command>" (without the quotes and <> ;) into the URL line, or go through the main menu. It also provides an interface to the other help system (info pages) but less nicely formatted (you can type "info:<command> invocation" into the URL line but in this case I think it's easier to navigate the menu system). :-)


linux and windows95

Mon, 17 Jul 2000 19:45:32 GMT
From: Michael Williams, Linux Gazette AnswerGang (linux-questions-only@ssc.com)

can u run linux and windows95 on the same computer and selecting whic operating system u want to run on the bootup?

Why, yes, yes you can. It's no easy process though, and you'll have to read a bit, so chek out

http://www.linuxdoc.org

Or more specifically:

http://www.linuxdoc.org/LDP/Linux+Windows-GUIDE/index.html

Installing Linux can mean re-partitioning, unfortunately. So be careful! There are ways to avoid re-partitioning, however. Check out:

http://www.vmware.com

Also, if you just wanna test out Linux, may I suggest Mandrake 7.0, which comes with a program called Linux for Windows, which will install Linux onto a FAT formatted partition.

Linux comes with a program called LILO (LInux LOader), which installs itself to the Master boot record, and can easily be configured to boot multiple OS's, such as Windows.

Mike


Computer Tax Credits

Wed, 19 Jul 2000 16:38:43 -0700
From: Jim Dennis, Linux Gazette Sr. Contributing Editor (linux-questions-only@ssc.com)

Sir:

Is there a program or programs that accept computer trade-in for tax credit?

Joe Kellum-NYC

Probably.

I did a Google (http://www.google.com) search on the phrase "computer donation tax" and got 35,000 hits. The first several appeared relevant.

However, this has nothing to do with Linux or with the free software movement. It's also not a technical question. Thus you've posted it to the wrong venue.

Perhaps you should talk to a tax professional.

[ The real tip here is, we're the Linux Gazette, not the tax writeoff gazette. You might try donating it to the Free Software Foundation, the Debian project, or a developer who is working on stuff your company uses, but is poor and could use the particular hardware you have. --Heather.]


recherche driver son

Wed, 12 Jul 2000 21:20:20 +0200
From: JOEL.MORALES (joel.morales@wanadoo.fr)

bonjour, je recherche un driver son yamaha labway olp3-sax, pouvez vous me dire comment faire sur internet pour le trouver ?

voici mon adresse : joel.morales@wanadoo.fr

merci d'avance � bient�t.    joel.

I thought I would need to post a translation request in Help Wanted again, but our assistant editor Don Marti stepped up to the plate:

Joel,

Il y a un driver pour le Yamaha OPL3-SA2 et OPL3-SA3 � ALSA:
http://www.alsa-project.org
Voici le HOWTO:
http://metalab.unc.edu/pub/Linux/docs/HOWTO/translations/fr/mini/Alsa-sound.gz

-- Don Marti


A Question!

Wed, 12 Jul 2000 09:49:16 -0700
From: Don Marti, Linux Gazette Asst. Editor (gazette@ssc.com)

On Wed, Jul 12, 2000 at 09:27:23AM -0500, Kishore T. Kapale wrote:

I want to connect a Laptop and a PC both running RedHat 6.2, through an ethernet connection. I do not need any technical details, I am aware of those. I have onlyone question, which is can I use thin 10Base2 network without a hub to achieve this?

Most laptop ethernet cards that I've seen use 10Base-T, or twisted-pair, Ethernet. If you have this kind of Ethernet on both systems -- it has an RJ-45 socket, like a wide version of a phone jack -- then you can connect two, and only two, systems with a crossover cable, available at any well-stocked computer store. Or build your own crossover cable using the diagram at: http://www.homepclan.com/cabcr20.jpg You'll need a tool called an RJ-45 crimper, which is a good investment if you want to make a lot of cables in custom lengths.

If you have true 10Base-2 Ethernet, which is rare these days, both systems will have a BNC connector, which is round with two little pins on the sides. Using 10Base-2 Ethernet, you can connect any number of systems without a hub. You'll need a 10Base2 cable (which is a coaxial cable, similar to what cable TV uses but different) a BNC "T" connector for each system, and a BNC terminator for each end. All available at any well-stocked computer store.

-- Don Marti


A couple questions

Mon, 17 Jul 2000 17:36:28 GMT
From: Michael Williams, Linux Gazette Answer Gang (linux-questions-only@ssc.com)

Hi,

I'm a newbie Linux user, and I just have a couple questions about my newly installed RedHat 6.0 system.

1. I'm trying to figure out how to run KDE from the console. Running startx brings up either GNOME, Afterstep or FVWM and I can't switch to KDE from any of those. I don't want to use GDM, and I found a script called 'kde' on my system, which of course doesn't work because the X server is not up. I found that 'X' was a symbolic link to my installed X server, and that brings up the familiar gray background and mouse cursor. I tried just switching to a console and running 'kde' again, hoping it would find the X server I just started.

Use a text editor (eg emacs), to edit: /etc/sysconfig/desktop

So that it now holds the string 'KDE' (excluding the quote marks of course)


Winmail.dat

Sat, 01 Jul 2000 13:03:00 +0200
From: "Anthony E. Greene" (agreene@pobox.com)
add'l: Heather Stern, Linux Gazette Technical Editor (linux-questions-only@ssc.com)

The Answer Guy, Jim Dennis, commented:

Of course it would be unfair to single out Microsoft in this regard. I don't like Netscape's "vcard" attachments any less obnoxious than "winmail.dat" and I find Netscape's previously default behavior of appending HTML formatted copies of the body text to all outgoing e-mail to be almost as bad as appending .doc or other binary formats. (At least I can read between the tags if I care to).

Netscape 4.72 (& 4.73?) still defaults to HTML mail, and vCards are an open standard (http://www.imc.org/pdi) that I have found very useful.

I have a web application that, among other things, sends the user's contact information to us via email. Adding these users to our address book becomes almost trivial thanks to an Outlook add-in that imports vCards. My application includes a vCard attachment with the message and we can double-click to add the user to a shared contacts folder. We could do something similar using Netscape, or any *nix mail client that called GNOMECard as a vCard viewer if we were using *nix desktops.

As long as sending a vCard is not the mail client's default behavior, I don't have a problem with it. It has more info than a plain sig, and since it's actually plain text, it's just as human-readable as an attached text file.

[ There is an Addreesbook written in perl which uses vCard format natively. Still working on vCard 3.0, but perhaps you can enjoy it anyway: http://www.acm.rpi.edu/~jackal/ab.html

XCmail is a mail client which handles vCards and PGP (among other things): http://www.fsai.fh-trier.de/~schmitzj/Xclasses/XCmail --Heather.]


SuSe Linux and Micrsoft medialess OS

Sat, 01 Jul 2000 12:14:24 -0400
From: Dwayne Miller (dmiller23@neo.rr.com)

Dear Linux Supporters:

I have started playing around with SuSE Linux and am impressed with the product. I have been a died in the wool Microsoft user for the last eight years. I have seen them step on a lot of folks and that is part of business. I have also put up with their mindless CD keys that make a network administrators life miserable. Not copy protected is what it said on all of their software. That was until they controlled the market now everything is copy protected.

But the latest rumor or plan that Microsoft has put me over the edge. I read the an article in the May 1, 2000 issue of INFO WORLD that Microsoft now wants to jam a "medialess OS" down our throats. The article is entitled "Users find Microsoft's medialess anti piracy play hard to swallow" explains their latest attempt to stop software piracy. This is it for me.

I have been an ardent supporter up till this. I want to convert to something else. The problems are my word, access and other apps that use MS apps. Is there a way to continue to use these apps without Microsoft OS. Or is there a way to emulate win apps or is there other apps that transparently use their files? Any help would be greatly appreciated.

Well as one newbie to another, good luck, Star office will import and save in most if not all the MS formats for office, personally I was using Star office on my MS machine, so I know it works at least for word, and excel, never used access or powerpoint, so cannot tell you how well those work.

This issue with MS medialess OS? I had not heard anything about it, but sure am glad I am switching over to Linx myself. Very tired of Micr$oft and its games, was waiting until I had found the apps needed to switch over and with the release of Coreal office for linux, I figured the time was at hand. Now to convince my wife.....

I am looking over the stuff for development on the KDE platform, namely the KDevelop IDE. If Microsoft would have developed something like this, and gave it way, Windows would not be the mess it is. Alot more developers would be able to work, without resorting to piracy to get the tools needed.

Good luck and have fun...


USR Modem

Fri, 9 Jun 2000 17:07:02 -0400
From: Heather Stern, Linux Gazette Technical Editor (linux-questions-only@ssc.com)

Douglas Macdonald (dmacdona@sas.upenn.edu) wrote:

I have a US robotics modem PCI Fax modem 3cp5610 and running Red Hat Linux. I can not get it to work. Any suggestions ?

[ You are a very lucky guy - you actually have an honest to goodness real modem there. So, you need to see what IRQ it's getting, and if necessary use setserial to advise Linux' drivers to keep it that way.

If you recompiled a kernel, double check that you have serial support. Also, in the "extended dumb serial options" turn on IRQ sharing. People who know modems a bit know that under MSwin 2 serial ports get the same IRQ, but a different I/O address. Same here, if you tell it so. --Heather.]


Boot Floppy for Linux

Sun, 09 Jul 2000 01:31:28 -0400
From: david sarraf (david.sarraf@paonline.com)

"I was wondering if you have ever heard of anyone booting up a system with a linux boot floppy. The system previously lacks the ability to boot from a CD , but after installing linux, uses the CD drive to install another operating sytem which at teh same time will write over the Linux system."

Noah:

Three different machines at work use boot floppies to start Linux. I have had problems using LILO and modifying the boot sector on two of those machines. Using a floppy gives me a safe and simple way to have Linux and Windows on the same machine with no changes to the boot sector. I did need to do an RDEV on the boot floppy's kernel to point it toward the proper partition on the hard drive. Other than that minor detail using a boot floppy works quite well.

Dave Sarraf


Diamond Stealth Pro VL and X -- A Contribution, I Hope

Sat, 22 Jul 2000 18:30:33 -0500
From: "Jeannine and Chris Gianakopoulos" (pilolla@gateway.net)

Hello, I have been playing with Linux for about 4 months, and I would like to share some information that may already be available, but not evident to me. My system has an older VESA local bus motherboard, and the processor is a 486DX2 running at 66 MHz. It took me approximately 2 months to get Xfree86 working with my Diamond Stealth Pro VL (VESA local bus) board which used an 80C929 device. Anyway, I want to prevent other Linux people from pulling overnight hacks like I did (that will never happen), so here is the section of the XF86Config file of importance for a Diamond Stealth Pro VL video board (VL for VESA local bus).
------------------------------------------------------------

Section "Device"

Identifier  "Diamond Stealth Pro"
VendorName  "Diamond Multimedia"
BoardName   "Stealth Pro VL"
VideoRam    2048
Ramdac "ss2410"
Option "diamond"
Clockchip   "icd2061a"
Chipset "s3_generic"

EndSection

------------------------------------------------------------
My Linux distribution is SuSE 6.4. The parameters in the above file reference the components in my video board.

The line which really made my system work without crashing while running X was the Chipset directive. The default chipset was mmio_928. When that option was used, I would get system hangs (you couldn't even telenet via the ethernet), segmentation faults, and lots of other problems. I will make the bold (and possibly incorrect) assumption that the assumed memory locations (for memory mapped I/O) were in conflict with the memory space of a running process (possibly kernel space?) I do not know for sure, but, using s3_generic (which implies I/O mapping for device registers) fixed the problem.

I am pleased that Linux came into existance, and it is one of the ultimate hacks. Your Linux Gazette has helped me lots and lots (I read all the back issues -- I am up to May 2000), and I hope that I can achieve the knowledge to help other people the way your extensive documentation has helped me.

Chris Gianakopoulos (soon to be Linux hacker)


ext2 fs question

Fri, 7 Jul 2000 13:28:37 -0500
From: Mike Perham (mperham@motive.com)
add'l: Heather Stern, Linux Gazette Technical Editor (linux-questions-only@ssc.com)

James, I find your Linux Gazette column to be very valuable. I have a problem that I have not been able to find the answer to: is it possible to get NT/2000 to read ext2 partitions seamlessly? I found a utility which will allow the user read-access but it is painfully slow and requires you to copy anything you want Windows apps to be able to access:

http://uranus.it.swin.edu.au/~jn/linux/explore2fs.htm

[ Yes, there is at the very least Ext2Read, which is a GUI to fit a package of loose tools originally designed for DOS, then ported for NT. It's reputed to work on W95, and appears to have a number of features. Note, I haven't used it:
http://www-scf.usc.edu/~vakopian/programs/progs.html#ext2read/

There's also EXT2 Researcher, but the documentation is slim. I haven't used it either:
http://winfiles.cnet.com/apps/nt/disk-analyze.html
--Heather.]

As an alternative, is there a way to transform the filesystem from ext2 to ntfs? Reformatting is out of the question as I have 30GB of data on the partition.

---- Mike Perham,
Java Server Guy


locate

Mon, 10 Jul 2000 09:03:22 -0700
From: Mike Orr, Linux Gazette Editor (gazette@ssc.com)

Somebody wrote a few days ago about how modern distributions have too many files and it makes the "locate" command unusable. Because anything you type matches a whole slew of pixmap and HTML files used for the desktop interface. The person was asking the distributions to move these into tar files.

Another strategy is just to filter those filenames out of the "locate" output:

loc () {
locate "$1" | egrep -v 'bmp|html|whatever'
}

This creates a shell function called loc, so that when you type:

$ loc time

you don't get back entries containing 'bmp', 'html' or 'whatever'. You can of course adjust the egrep expression to your heart's content.

-- -Mike


Summing up a column of numbers

Wed, 26 Jul 2000 15:40:52 -0700
From: Mike Orr, Linux Gazette Editor (gazette@ssc.com)

Recently I had to sum up a column of numbers appearing in a tab-delimited text file. The following awk program 'summ' worked well, in conjunction with a few other tricks.

#!/usr/bin/awk -f

{
total = total + $1
}

END	{
print total
}

Assume the data file contains:

aaa 44 asdf bbb 55 asdf ccc 67 asqq
$ cut -f2 data.txt | summ
166

If I wanted to process only some of the lines, I can put a 'grep' before it:

$ grep 'asdf' data.txt | cut -f2 | summ
99

If I wanted, I could move both these operations into the awk script. The "1" in $1 could be replaced by any column number, and I could put a regular expression before the first bracket:

/asdf/	{
total = total + $2
}

However, I prefer one generic script. I wanted to call it 'sum' but the name was already taken. ('sum' produces checksums.)

-- -Mike


Return to spellcheck

Wed, 31 May 2000 02:29:55 +0100 (BST)
From: Joseph Petrow (joepet@searchspell.com)

Hi,

I happened upon your article at
http://www.linuxgazette.com/issue44/tag/17.html

In regards to spellchecking for homonyms, I have built a web search spellchecker at http://www.searchspell.com. It is a lookup database of misspellings using ePerl and MySQL on a Linux box. It allows me to customize spelling rules for particular rules, and even recommend possible corrections to words with correct spellings ("hear" for "here", "where" for "wear", etc.) Before reading your column I did not have "hoard" and "horde" in my database, but that is now fixed, and I'm tracking down more and more everyday.

Currently my database has over 2,000,000 entries, which I'm able to permute in billions of typo corrections, and each day I'm getting closer to a true "intelligent" spellchecking system.

If you have some spare time, please check it out.

Regards,
Joe Petrow


redhat ifup/ifdown problems

Sun, 18 Jun 2000 19:27:26 -0500
From: Dan Watling (dwatling@mc.net)

Hey,

I'm having some trouble with allowing regular users to control the ppp0 connection. I even enabled "Allow any user (de)active the interface" under netconf. Essentially what happens is the user types in "ifup ppp0" or "ifdown ppp0" and it sits there without ever doing anything. Any ideas or suggestions would be appreciated.

[ You could install mserver, then let the users have a masqdialer client each; they even exist for Windows. But the question is still a good one; why does this hang? --Heather.]

Also, would you happen to know of a Linux help site that is in message board format?

Thanks. -Dan


Tips in the following section are answers to questions printed in the Mail Bag column or comments on AnswerGuy mail from previous issues.


ANSWER: grep

Sat, 8 Jul 2000 18:27:15 -0400 (EDT)
From: Jason Dixon <jason@nimbus.skycache.com>

Hi Angus:
The quickest, easiest way to do what you want is just to extend your expression a bit...

finger | grep 'potatoe ' <instead of> finger | grep potatoe

Note that I added the quotes, with the trailing space. This will match all instances of "potatoe" with a trailing space (for example, a username). However, hostnames (potatoe.onthefarm.com) won't match because of the trailing ".".

Hope this helps!

Jason Dixon
Systems Engineer


ANSWER: Grep

Tue, 11 Jul 2000 13:41:48 -0700 (PDT)
From: Srinivasa Shikaripura (srinivasa_sa@yahoo.comi)

hi,

Things you could try are:

  1. Try 'finger -s| grep "^potato"', which greps all the user names starting with potato.
  2. You could use 'awk' to do whatever you want to (currently I am not in a mood to dig an awk script, it's been long!)
  3. Also look into 'cut' command where you can cut fields of a multi-column line, which also could be used to do some tricky things.

As advice, learn about regular expressions in *nix. The first solution above, used the '^' symbol to indicate to grep to get the lines starting with potato. You could do many such things with regular expressions...

Hope that helps.

cheers -Sas


ANSWER: Netscape 2c tip

Fri, 07 Jul 2000 15:29:50 -0700
From: Sudhakar Chandra (thaths@netscape.com)

Matthew Willis (matt@optimus.cee.cornell.edu) wrote;

You can get a two-column printout from netscape by using the psutils packages. For letter-sized printouts, just change your "Print Command" in netscape to

pstops -q -w8.5in -h11in -pletter "2:0L@0.7(8.in,-0.1in)+1L@0.7(8.in,4.95in)" | lpr -h

The PSUtils are avalable at
http://www.dcs.ed.ac.uk/home/ajcd/psutils/index.html

You will have to edit the Makefile and set PAPER=letter if you live in North America.

Why bother with such a verbose command. Part of the psutils package is a program called psnup. The preceding verbose command can be replaced by:
psnup -c -n 2 | lpr -pprinter
psnup has also been hacked (by yours truly ;-) to generate back-to-back postscript documents. See http://www.aunet.org/thaths/hacks/psutils
Thanhs
Sudhakar C13n


ANSWER: ppp-compress-xx

Sun, 2 Jul 2000 17:40:50 +0200 (MET DST)
From: "Werner Gerstmann" (101.234011@germanynet.de)

Hallo Jim,
your question in LG#55: You simply have to put into the conf.modules or modules.conf file in the etc directory:

alias ppp-compress-21 bsd_comp
alias ppp-compress-24 ppp_deflate
alias ppp-compress-26 ppp_deflate

and reboot. Regards Werner Gerstmann


ANSWER: File formats!!!

Tue, 11 Jul 2000 13:28:52 -0700 (PDT)
From: Srinivasa Shikaripura (srinivasa_sa@yahoo.com)

hi,

There are definitely well defined file formats. If you are looking for Windows/Dos, the file formats are .COM and .EXE. To get to know about these formats refer to any standard assmbly language book, like "Introduction to assmbley languge" (not sure about the title) by Peter Norton and Socha.

In *nix world there are two famous execution file formats(AFAIK), "a.out" and "elf (Executable and Linking Format)". "a.out" is a little old standard and Linux came out of that format sometime back. elf is a old but very generic and good one.

There is a standards document somewhere which defines the format of an elf file. Even you could try 'man elf' and it could tell you something.

In short, elf file contains a number of sections, one for each of constant-data, un-initialized data, executable code, startup-code and debug-info tables.

May be if you look at programs like objdump or elf library (libelf.o) related header files, you would get interesting things.

Hope that helps a little.

cheers -Sas


ANSWER: KPPP Question

Tue, 11 Jul 2000 09:55:35 -0700 (PDT)
From: adh math (adh_math@yahoo.com)

Dear Ms. Parker,

I hope you've gotten your question posted at Linux Gazette answered by now (six weeks later), but in case not, here are some suggestions:

In the KPPP Setup dialogue, under the IP Address tab there's a box "configure hostname automatically"; *un-check* this box.

KPPP does indeed edit /etc/resolve.conf, but if (under the DNS tab in Setup) you do not check the box "disable existing DNS servers" then your default DNS server (e.g., your local caching DNS server, if you've set one up) should also work, and will be tried before your ISP's DNS server is consulted.

Again, I hope this is not helpful (i.e., that you've already gotten things working again :).

adh


ANSWER: about stripping libraries

Tue, 11 Jul 2000 13:14:19 +0200 (CEST)
From: Dario Papoff (papoff@jetai.org)

Hi,
when you strip a library with strip or objcopy --strip-all you don't wipe out the dynamic symbol table, this mean that static libraries become useless but when you strip a dynamic library you don't loose dynamic symbols (have a look with nm -D or objdump -T on your stripped library) and so library functions can be still referenced

Bye, Dario Papoff


ANSWER: kppp playing up

Sun, 2 Jul 2000 17:41:38 -0400
From: Pierre Abbat (phma@oltronics.net)

I have a LAN, so my boxes have 192.168 addresses, but I use kppp as you do. Here are the relevant options:

Bring up kppp, hit Setup, under the Accounts tab select the ISP, and hit Edit.

IP: Uncheck "Auto-configure hostname".
DNS: If you run your own name server, the address list should have only 0.0.0.0.

Some versions of libc will not work if /etc/resolv.conf has the word "localhost" in it. If "Disable existing" is checked, the contents of /etc/resolv.conf will be commented out while you are on line.

phma


ANSWER: Intel i810

Sun, 25 Jun 2000 11:23:02 EDT
From: GregV (Kvgov@aol.com)

Dear Answer Guy,

Searching for more inormation about the i810 chipset I came across your discussion about it and Linux.

I had a similar porblem with my Linux installation, where as Linux installed fine and I could utilize the command line wihtout a problem. However I had no graphics support, that is to say no XFree86.

The soultion to this porblem is to be found at support.intel.com, under the i810 fourm site. They have the X server and Kernel module and complete instrcutions for how to install and use the software. You must however read the fourm posts as there are a few tricks to the setup procedure.

That being said, I would like to know when/if kernel support will be provided for the i810 chipset. Actually I would rather learn how to find this information for myself. If you teach a man to fish, etc....

Thanks,
GregV

[ Xfree86 is a userspace application; the kernel is only involved a tiny bit for video (unless you use framebuffer, then kernel space is doing a lot of the work). A good way to search is to download a current kernel source package from kernel.org, install it, and grep around in its Documentation/ directory. You can also give keywords you find here (like "AGP" "framebuffer" etc.) to normal search engines like the Gazette's own, or Google! -- Ed.]


ANSWER: fsck

Tue, 11 Jul 2000 11:19:10 -0700 (PDT)
From: adh math (adh_math@yahoo.com)

Dear Mr. Gauthier,

When you run fsck (or e2fsck) on a filesystem, it is very important that the filesystem be mounted read-only; otherwise fsck will do further (possibly severe) damage to the filesystem being checked.

As you may know, Linux stores data in RAM buffers, so when there's a sudden power-out, a lot of data about the running system is lost. However, unless the power goes out while you're booting, I don't think you should lose configuration files like inetd.conf. That's what makes me suspect that fsck was run on a read-write filesystem.

Recent kernels (2.2.14 or later, say) are better about syncing RAM buffers to the disk every minute or so (so less data is lost in a crash), and ext3 (the new filesystem type) handles crashes better than ext2 (in theory :)

About desktop applications, KDE allows you to add executable icons on your desktop; right click on the desktop and select "New Application" in the dialogue box that pops up, then fill in information as directed. You should have a couple of clock programs, such as "xclock", "oclock", perhaps even "daliclock" (perhaps this is a GNOME program...?).

Hope that's helpful.

adh


ANSWER: RH Upgrade Problems

Mon, 10 Jul 2000 04:13:12 +0100 (WEST)
From: Luis Pinto (lmpinto@student.dei.uc.pt)

Hi! I saw your question on Linux Gazette, which i try to respond:

After the upgrade, you have probably erased your /etc/X11/XF86Config. Now, the computer is trying to boot X upon the linux boot because you have the line:

id:5:initdefault:

in your /etc/inittab file. You must change the number 5 to 3. To do so, you must boot giving the 'single' option to LILO:

LILO boot: linux single

Then, you must edit the /etc/inittab file, change the previous line, and reboot. After that, you must use Xconfigurator, XF86Setup or any other tool to configure your X.

Hope to have helped...

Luis Pinto


ANSWER: linux crash

Sun, 2 Jul 2000 17:53:36 -0400
From: Pierre Abbat (phma@oltronics.net)

You may have a bad sector. I had a bad sector in the inode area, and every so often a file would land there and cause havoc. The worst was when /etc/mtab landed on the bad inode. The computer couldn't tell what was mounted and refused to boot. I fixed it with fsck -c .

phma


ANSWER: Port forwarding

Tue, 11 Jul 2000 11:46:29 -0700 (PDT)
From: adh math (adh_math@yahoo.com)

Dear Mr. Adams,

Regarding your June 15 post at Linux Gazette, you might swing the desired arrangement with port forwarding on the proxy server (ipportfw, one of the IP masquerading utilities), but it may not be easy (read: impossible if you don't have root access on the proxy, merely difficult otherwise). I'm pretty sure it's impossible if the proxy is also accepting HTTP connections on port 80, since you can't (to my knowledge) run two services on the same port.

Even if the technicalities can be overcome, there are good reasons not to allow telnet connections through your proxy firewall's www port:

  1. Your employer is presumably monitoring all network activity, and may not appreciate having the firewall breached (or circumvented, if you prefer).
  2. It makes the firewall and the network behind it more vulnerable to attack (because it complicates the routing rulesets, opens another port/service, etc, etc).
  3. Telnet sends clear text passwords, and should not be used for any reason over a non-private network; ssh (secure shell) is a no-cost, open source, encrypted replacement, and is very easy to compile and install (again, if you have root access).

(That's just off the top of my head...I'm confident there are other good reasons :)

Well, not to lecture, but it sounds like a bad idea to me. More positively, I think you'd do better to convince your employer to run an SSH server inside the firewall, and/or to allow outgoing SSH connections.

Sincerely,
adh


ANSWER: re: linux booting

Tue, 11 Jul 2000 00:10:04 -0500
From: Jim Liedeka (jliedeka@facstaff.wisc.edu)

I have run into the problem you are describing. I added a SCSI card to my machine which hosed Win95. I never did get Win95 working but I kept hosing my boot sector trying to reinstall it. The solution is really pretty simple.

  1. Obtain a boot disk. If you don't have one, you can make one from linux by typing (as root)
    mkbootdisk --device /dev/fd0 <kernel version #>
  2. This will save you some time, copy down the information from /etc/fstab related to your hard disk partitions. When you boot from the floppy, nothing will be mounted for you. You have to do it manually.
  3. Boot from the floppy and type "rescue" at the lilo prompt.
  4. Now you are in a minimal linux environment. You won't have all the nifty commands but that's okay. You need to mount your / partition and possibly other partitions if /etc, /sbin, /boot and possible /usr and/or /usr/local.
  5. chroot /, this isn't strictly necessary but the other way is much harder.
  6. run /sbin/lilo. That should rewrite the boot sector and allow you to boot with lilo.

I wrote this from memory so I may have left out a step or two but I hope this will give you the idea.

Jim


ANSWER: Anyone out there know more?

Tue, 11 Jul 2000 10:47:00 +1000
From: chimera (chimera@alphalink.com.au)

I think either objcopy or strip can be used. However, the Linux Bootdisk HOWTO says that only debug symbols should be removed (--strip-debug). What would happen if everything is removed (--strip-all)? I have tried and the resulting boot/root disk seems to be OK. However, something must be wrong ...

P> I found this out after some hair-pulling exercise. Some distributions have a "depmod -a" in the initialisation scripts. This uses the object symbols to resolve the dependances between modules. If you strip all, depmod cannot resolve and hence cannot work out that whenever you load sound.o you will also need to load sb.o.

If your bootdisk already has a depmod, then I suppose you can strip-all to save space. There maybe other reasons why you shouldn't do a strip-all that I don't know about.

chimera


ANSWER: Linux Voice Mail, etc.

Mon, 26 Jun 2000 13:05:21 CDT
From: Heather Stern, Linux Gazette Technical Editor (linux-questions-only@ssc.com)

Norman King (cable4096@hotmail.com) wrote:

I saw a post by you on the Linux Gazzette about Voice Mail, E-Mail, Faxes, etc. integrated on Linux. You said it was possible via scripts, but you did not cite any examples of software to use to do this.

I have seen mgetty+sendfax but it is not ready for prime-time and won't work with but a few voice modems, and even still, doesn't always work and is in the beta test stage.

Do you know of any open-sourced, shareware, freeware, or commercial Linux solutions that do all of this that costs under $200 if commercial?

Thanks.

[ You could certainly try HylaFax, it is open source and absolutely free. Specifically, the fellow who wrote it works at SGI, and they let him give it away, as long as they get to disclaim everything and not be involved in it. So check out http://www.hylafax.org right away :)

There are probably others, I'm sure we'll get notes about it now. --Heather.]


This page written and maintained by the Editors of the Linux Gazette. Copyright © 2000, gazette@ssc.com
Published in Issue 56 of Linux Gazette, August 2000
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