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The Mailbag From The Readers of Linux Gazette

• H/W detection in Debian ?
• ppp over nullmodem cable - no response to (LCP ConfReq ...)
• How can we block mails from users using ipchains
• dual boot problem
• Custom kernel, not so custom modules
• ipchains vs iptables

H/W detection in Debian ?

Hi all,

1. kudzu is the DEFAULT H/W detection tool in RH & harddrake in MDK. is there anything in debian?
2. I have installed kudzu in debian 3.0 , but it is not running as a service. it needs to execute the command kudzu manually. more over it couldn't detect my epson C21SX printer. but under MDK 9.0 kudzu detected the printer . any solution please ?

thanks in advanced.

ppp over nullmodem cable - no response to (LCP ConfReq ...)

hi linux gazette

first thanks for your great work.

id like to connect over a serial cable to a windows 2000 ras server. i already know that the problem isnt the null modem cable, because i just could remote control my second computer while using getty and windows's hyperterminal on the other side. (btw i first tried gnu/linux's minicom instead of window's hyperterminal but it seemed to me minicom just works with a modem a the end of the cable, am i wrong or is there any other program out there which i should give a try ?) ok ive already read those Serial-* and PPP* howto but i probably missed something. further, i also set the same baud rate at the ras server side. so any idea, why i dont get any reply to my LCP ConfReq Request ??

greets

josef

melee:/home/josef/tmp# pppd /dev/ttyS0 nodetach
Serial connection established.
using channel 1
Using interface ppp0
Connect: ppp0 <--> /dev/ttyS0
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x143c91f8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x143c91f8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x143c91f8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x143c91f8> <pcomp> <accomp>]
....

my /etc/ppp/options.ttyS0

connect 'chat -v -f /etc/ppp/scripts/winserver.chat'
19200
debug
crtscts
local
user josef
noauth

How can we block mails from users using ipchains

HI,

I would like to know how to block mails from other users on the same system.I tried using 'ipchains' & port no,but it didnt work.Please help me with this.

Thanks

Perhaps you could be more specific about what you're trying to accomplish. For example:

• I wish to block all mail from a specific user to me
• I wish to prevent a specific user from sending any mail
• I wish to allow users to send mail, but not to other users on the same system
• I wish to prevent any mail from being sent on the system
• ??

I'll take this one to the readership as a general request for more articles about setting up mail systems to do interesting things. In fact, some things that aren't really about spam could be a fun read -- Heather

dual boot problem

I installed Redhat 8.0 on an existing system that has XP pro on it. XP is on ide0 and the Redhat is on ide1 XP hard drive is fat file system. When it boots it asks go to Redhat or dos… I don’t have dos. How do I get back to the windows? What needs to be done to change the boot loader. I thought I had set it up so Linux only booted with a floppy… I guess not Thanks for any help. Phil Harold

Go ahead and choose "DOS". That will boot into the other partition which is set up (hopefully) to boot XP.

Looks normal so far. Hardly worthy of the "help wanted" section here at the Gazette ... but nope, it's a stumper. -- Heather

just before the other symbols it says:

root no verify (hd2,0) chainloader +1

hit the enter key is when the symbols come looks like greek and chinese

Custom kernel, not so custom modules

An old question - he had said this relates to [[http://www.linuxgazette.com/issue64/tag/16.html][issue 64 #16 in The Answer Gang]] - but still a stumper. We have a lot more readers now; maybe one of you knows what happened here? -- Heather

Hello all,

I have exactly the same problem described by Michael Hansen. Modules doesn't load after recompile Kernel. I'm also a newbie in Linux, but I see (If you are using red hat at least), it creates a directory /lib/modules/2.4.xcustom (in fact kernel version pass to 2.4.18custom in my case), but when you do make modules it copies to directory 2.4.x. If you rename directories the problem comes when you try to install a new driver that use uname -r command during installation to find modules directory (uname -r result is 2.4.xcustom). I don't know how solve this problem.

Best regards

ipchains vs iptables

Dear Answer Gang members,

I have a linux home network which is connected to the internet through a gateway. This computer runs linux with a 2.2.18 kernel. I use IP-chains to block some unwanted incoming traffic. One of the machines runs mldonkey. This program needs the ports 4161 and 4162. I get the following error from server i contact:

ERROR: Your port 4662 is not reachable. You have a LOWID.

This port is open. The solution to this problem seems to be to redirect incoming packets from the internet for port 4662 directly to the machine where mldonkey runs.

The following iptable should do this:

iptables -A PREROUTING -t nat -p tcp -d $4 --dport 4662 -j DNAT --to 192.168.1.100


$4 is the gateway
192.168.1.100 runs mldonkey

I use a 2.2.18 kernel with ipchains on the gateway. In Howto's and other documentation i can't find a way to do this with ipchains. Do you know if it's possible and how?

Please your help.

greetings Dean Buhrmann.

Articles about trevails, with details are always welcome when you solve a strange problem. Of course there are HOWTO's for ipchains and for netfilters, but perhaps we could see an article about do something complicated enough to illustrate differences that might have you prefer one or the other interface. -- Heather

• Re: your mail
• POS Software in Linux

Re: your mail

I had an IBM 20G hard drive that had a lot of bogus information in the master boot record due to formatting it with 2G jumper on and then formatting with the jumper off. It wouldn't load an OS, and it locked up every time I tried to run fdisk, norton disk doctor couldn't fix it either, but your little DOS assembly program http://www.linuxgazette.com/issue63/okopnik.html saved my hard drive.

Thank you!

Glad you found it useful, Larry. A number of people have written in with comments like yours about that particular article; I find it very pleasant that my work has benefitted that many people.

I appreciate your letting me know.

POS Software in Linux

Hi!

I was reading the December 2002 issue of LG (btw, great magazine! I've just re-discovered it, and it's fantastic!) and I saw the PC-MOS thread originated by Reilly Burke.

I remembered that I saw something like a prototype for a POS software on the net and I went searching for it. The address is http://www.dnalounge.com/backstage/src/pos and the author is no other than jwz (Jamie Zawinski).

As fas as I can see, there is only an idea and a "little prototype" (as the author describes it), but maybe this prototype can be used for further developement by somebody else.

HTH!

If you need a restaurant-specific POS and don't mind going commercial (for a very small fee as compared to other POSes, actually), I have only good things to say about the ViewTouch POS <http://www.viewtouch.com> in spite of its closed-source nature. The interface is very well thought-out and beautifully done; the layout, menu, employee, and ingredient list configuration is a snap. It supports all the popular touchscreens, industry-standard narrow printers, and all the standard cash drawers. Despite the documentation that insists on "RedHat-only" compatibility, I've run it under Debian from day one (three years or so ago), and it works fine.

My biggest concern with it, of course, is that it is closed-source. I would have liked to tweak some minor features for the client I had who was interested; as well, I wonder what would happen if the developer disappeared off into the ether... but that's the nature of that particular beast. It is, however, an interesting and well-executed option. Interestingly enough, I spotted a major restaurant near Baltimore (a Brazilian steakhouse in Columbia, MD) using it about a year ago. The employees using it didn't have any negative comments, either.

P.S. Keep up the good work!

Thanks, Stelian. That's the reality and the plan.

• Wanted: Proofreaders
• Compilation Problem in Writing Your Own Toy OS (PART II)
• publishing

Wanted: Proofreaders

LG is looking for proofreaders. The main qualifications are a good command of English grammar, a native or near-native sense of English word usage, and the ability to recognize and clarify phrases that are too academic, not understood outside their own country, or unnecessarily difficult for those with limited English ability to read.

Depending on the number of proofreaders, the workload would be at most one article per month, but more likely one article every 2-3 months. Of course, you would be able to refuse articles you don't have time to proofread, or if you're not interested in the subject.

If interested, send gazette@ssc.com some samples or URLs of stuff you've written or proofread (any topic, any length) that demonstrates your wording style.

Compilation Problem in Writing Your Own Toy OS (PART II)

Dear Sir,

"Writing Your Own Toy OS" is a Great Contribution towards knowledge.

I have tried PART I successfully.

But, after compiling part II, I booted my system from Drive A. System checked Drive A and was hangged. There was no output of the string.

Could you please help me out.

Best Regards

M. R. Moghal

Forwarding to the author, Krishnakumar R.

He fixed one of the programs somewhere in the series after it was published, but I don't remember exactly where. If you're reading on a mirror, check the main site, and see whether that program has been changed. http://www.linuxgazette.com/issue79/krishnakumar.html -- Mike

publishing

Readers, please note that this was actually an exchange of mails back and forth between Mike and Felix, rather than one message which Mike responded to in gory detail. If anyone out there, either in whole or in part, takes on the Herculean task of providing paper editions of LG please let us know - we will very happily spread the word! -- Heather

Have you ever thought of publishing the gazette and require subscriptions? I would sure like to get a monthly magazine then browsing the gazette online.

We've had several requests for a print version of LG. However, the cost of producing it would be prohibitive. (Printing, postage, software to track subscriptions, customer service staff, etc. And if you want a glossy magazine rather than just a xerox copy, there's layout costs, more printer's fees, etc.) Commercial magazines like our Linux Journal can do it because most of their revenue comes from advertising, but Linux Gazette does not accept advertising (except sponsorships).

We have repeatedly asked if any readers would be willing to set up their own print-and-distribute service for LG, but nobody has offered.

What kind of equipment would be required to print-and-distribute services?

At minimum, a lazer printer, envelopes, stamps, and a list of subscribers. That's how small, do-it-yourself zines work. You'd want some kind of cover or binding unless you're just going to send a stack of loose sheets.

But mailing costs alone will soak you, especially since a single issue of LG is something like fifty printed pages. (I've never printed an issue, so that's an estimate.) Sending fifty pages via first-class mail within the US is $3-4, so that's $48/year. Would you pay $48 for LG? You may be able to get a better deal with book rate or presorted rate but you'd have to check with the post office. But how will you recoup your cost for toner cartridges, paper, printer repair/replacement (since it will wear out sooner), envelopes, and the time to write the addresses or attach labels, not to mention the time dealing with subscription requests, complaints about "I didn't receive my issue", etc?

Today many free magazines put ads into the magazine and make money to publish the magazine. It would be a good idea to maybe advertise, but I'm not sure if LG has a high number of subscribers. I can see where the management issue would be a problem (billing, distributing, etc). Hopefully one day maybe.

LG has a huge number of readers all over the world. I don't know the number because people who read via mirrors or off-line are uncountable. But there are mirrors in fifty countries, and I figure any country with a mirror must have a subtantial LG readership. Either that, or it at least has one LG fanatic....

You bring up an interesting point. LG itself is not interested in running ads, at least not at present. I like to think of LG as an ad-free zone, a safe haven from ads. But since LG content is freely redistributable, there's nothing prohibiting a print-and-deliver service from inserting ads in their version.

Actually, our author Alan Ward in Andorra said he's seen a Spanish print version of LG on the newsstands there. I assume it was the Spanish translation of Linux Journal, which may include some LG articles.

I've seen few sites publishing their works into magazine (including ads) and subscribers did not get angry at the ads, because they understood that to publish costs money and if the work is quality it's worth subscribing for.

HAPPY NEW YEAR and good luck.

There are a few articles in LG that may not be redistributed in a commercial print publication (where "commercial" means you're charging any amount of money for it). Those articles have a message to that effect at the bottom of the article. The ones that come to mind are:

• Some of Shane Collinge's HelpDex cartoons: he sold the print rights to a certain publisher. This affects only a limited number of cartoons.

• One or two other articles that have corporate ownership.

In those cases, you will have to contact the author for permission.