Linux-Networking Digest #211, Volume #12 Fri, 13 Aug 99 08:13:38 EDT
Contents:
Re: ?LINUX IP masquerading ("Graham Fountain")
Re: ?LINUX IP masquerading ("natarajs")
Re: Domain Problems - Someone else is aliased against my domain (Jeff Peterson)
samba (mike)
TIME_WAIT with TCP socket (Fang Sun)
Re: Send an AT command to modem ("Aldog")
Win95 -> linux -> internet (Khoo Yit Phang)
telnet to slow from W95 ("ArTec - Vincent MAURY")
Serial Cards for Linux for PPP Server in the UK ? ("David Travers")
Re: ipchains Newbie Q (DHobbs)
Re: My first Network install - N (Lindoze 2000)
Masquerading - Re: LinkSys Etherfast 10/100 (I know...) (David Crooke)
Sendmail Problems (Lederhaas Horst)
----------------------------------------------------------------------------
From: "Graham Fountain" <[EMAIL PROTECTED]>
Subject: Re: ?LINUX IP masquerading
Date: Fri, 13 Aug 1999 14:14:59 +1000
natarajs <[EMAIL PROTECTED]> wrote in message
news:gqLs3.1718$[EMAIL PROTECTED]...
>
> GOt my RH 6.0 connected to the Internet through PacBell DSL.
>
> Having problems using my Win95 machine to see the Internet through my
> Linux machine
> using IP masq.
<snip>
> Question: Do i have to have 2 NIC cards on my linux machine and have
> 192.168.x.x
> address on one of the cards and have the win95 machine also have the
> 192.168.x.x address.
Yes, in a nutshell. Tell the win95 machine that its gateway address is the
ip address of the linux machine.
Firstly on the linux machine you will need to enable ip forwarding:
echo "1" > /proc/sys/net/ipv4/ip_forward
Then, (assuming you have kernel 2.2.x) run ipchains as follows:
ipchains -P forward DENY
ipchains -A forward -s 192.168.1.0/24 -j MASQ
If you have a 2.0.x kernel you will need to use ipfwadm - someone else will
need to tell you how to use it, I dunno.
The first ipchains line sets the forward policy to deny to stop packets
being able to travel between the internet and your lan. The second line
does the masquerading, so packets sent to the linux machine from the
192.168.1.x subnet get retranslated to have come from the linux machines
real internet address. To get ftp and a few other services running there
are a few additional modules that need loading.
I assume you have some sort of cable modem setup - don't know a great deal
about these, they haven't hit oz yet, but I wouldn't be surprised if your
current setup is trying to put your win95 machine on the net as
209.x.x.155 - depending on how stuff at pacbel is configured, this could
cause anything from not working (which it seems to be doing) to interfering
with the person really has 209.x.x.155.
You may also be able to do it without adding a second net card to your linux
machine, I don't know if this will work or not, but ifconfig can be used
(apparently) to assign multiple ip addresses to one card. With this method
you would assign both 209.x.x.154 and 192.168.x.x to the linux machine. All
the other configuration with ipchains etc would remain the same. I don't
have the info on setting up a second ip address handy with me, and i haven't
done it, so i can't tell you if it works. I would assume that setup in this
fashion the system would behave as if it had two cards in it.
Hope this helps!!
>
> What am i doing wrong ?
>
>
> nataraj/
> [EMAIL PROTECTED]
> --
> Posted via Talkway - http://www.talkway.com
> Exchange ideas on practically anything (tm).
>
------------------------------
From: "natarajs" <[EMAIL PROTECTED]>
Subject: Re: ?LINUX IP masquerading
Date: Fri, 13 Aug 1999 04:18:13 GMT
On Fri, 13 Aug 1999 14:14:59 +1000 "Graham Fountain"
<[EMAIL PROTECTED]> wrote:
>
> natarajs <[EMAIL PROTECTED]> wrote in message
> news:gqLs3.1718$[EMAIL PROTECTED]...
> >
> > GOt my RH 6.0 connected to the Internet through PacBell DSL.
> >
> > Having problems using my Win95 machine to see the Internet through my
> > Linux machine
> > using IP masq.
> <snip>
> > Question: Do i have to have 2 NIC cards on my linux machine and have
> > 192.168.x.x
> > address on one of the cards and have the win95 machine also have the
> > 192.168.x.x address.
> Yes, in a nutshell. Tell the win95 machine that its gateway address is the
> ip address of the linux machine.
> Firstly on the linux machine you will need to enable ip forwarding:
> echo "1" > /proc/sys/net/ipv4/ip_forward
>
> Then, (assuming you have kernel 2.2.x) run ipchains as follows:
> ipchains -P forward DENY
> ipchains -A forward -s 192.168.1.0/24 -j MASQ
> If you have a 2.0.x kernel you will need to use ipfwadm - someone else will
> need to tell you how to use it, I dunno.
>
> The first ipchains line sets the forward policy to deny to stop packets
> being able to travel between the internet and your lan. The second line
> does the masquerading, so packets sent to the linux machine from the
> 192.168.1.x subnet get retranslated to have come from the linux machines
> real internet address. To get ftp and a few other services running there
> are a few additional modules that need loading.
>
All of the above are done.
`
> I assume you have some sort of cable modem setup - don't know a great deal
> about these, they haven't hit oz yet, but I wouldn't be surprised if your
> current setup is trying to put your win95 machine on the net as
> 209.x.x.155 - depending on how stuff at pacbel is configured, this could
> cause anything from not working (which it seems to be doing) to interfering
> with the person really has 209.x.x.155.
>
I believe that is the problem.
> You may also be able to do it without adding a second net card to your linux
> machine, I don't know if this will work or not, but ifconfig can be used
> (apparently) to assign multiple ip addresses to one card. With this method
> you would assign both 209.x.x.154 and 192.168.x.x to the linux machine. All
> the other configuration with ipchains etc would remain the same. I don't
> have the info on setting up a second ip address handy with me, and i haven't
> done it, so i can't tell you if it works. I would assume that setup in this
> fashion the system would behave as if it had two cards in it.
>
This is what i would like to find out.. whether i can use 1 NIC and
assign
2 IP addresses to it or do i need 2 NICs.
Will dig into that ifconfig aspect. Thanks for the pointer.
> Hope this helps!!
>
Definetly! Thanks
> >
> > What am i doing wrong ?
> >
> >
> > nataraj/
> > [EMAIL PROTECTED]
> > --
> > Posted via Talkway - http://www.talkway.com
> > Exchange ideas on practically anything (tm).
> >
>
>
--
Posted via Talkway - http://www.talkway.com
Exchange ideas on practically anything (tm).
------------------------------
From: [EMAIL PROTECTED] (Jeff Peterson)
Subject: Re: Domain Problems - Someone else is aliased against my domain
Date: Fri, 13 Aug 1999 04:18:21 GMT
I received an email from Register.com yesterday saying they screwed
and updated the MX record for me.
>
>It all seems fine to me.
>
>
>clifto:~$ host -l norske.org
------------------------------
From: mike <[EMAIL PROTECTED]>
Subject: samba
Date: Fri, 13 Aug 1999 10:30:43 GMT
upps
================== Posted via CNET Linux Help ==================
http://www.searchlinux.com
------------------------------
From: Fang Sun <[EMAIL PROTECTED]>
Crossposted-To: comp.unix.programmer,comp.protocols.tcp-ip
Subject: TIME_WAIT with TCP socket
Date: Fri, 13 Aug 1999 12:29:11 +0200
Hi,
Does anybody know how to change the TIME_WAIT value for tcp
sockets on closing?
In my project, I build a server for receiving data from many clients.
When a client wants to send data to the server, it makes a connection
to the server, and closes it after data is transfered.
For our project, we can not use fixed connection between client and
server.
During my testing, I encountered "Try Again" error from connect
function at client side.
When it happens, use netstat, I can see thousands of TIME_WAIT.
>From what I understand of sockets, the client runs out of resources
for sockets because of the "TIME_WAIT".
On my PC(PII-450, linux-2.2.5), the value for TIME_WAIT looks like
about 60seconds.
I am sure, for the server side, I got all data sent by client.
There is no such TIME_WAIT problem on server side. Server can close
the connected socket very fast.
So that I would like to decrease the value for TIME_WAIT on close.
Then I can get higher sending rate for a client.
Does anyone know how to do that ?
Thanks in advance.
Fang Sun
DESY -IfH Zeuthen
------------------------------
From: "Aldog" <[EMAIL PROTECTED]>
Subject: Re: Send an AT command to modem
Date: Fri, 13 Aug 1999 04:43:19 GMT
Hi Dave,
On RedHat 5.2, I can think of two simple ways to do this. They both rely on
the fact that my modem is treated as a file device. On my system, the modem
is /dev/modem which is a symbolic link to cua3. This naming convention
may be different for you if you are running RH6.0 or some other
distribution.
(1) 'cat' a file with the atdt string to the /dev/modem device.
I create a file called atdt.dat with 1 line containing my at command
string.
Then just issue: cat atdt.dat > /dev/modem
(2) 'echo' the string directly to the /dev/modem device.
echo "ATDT123-4567,,,,,911#"\n > /dev/modem
(Note: the modem needs a carriage return to terminate the AT command. The
'cat' command does this automatically, the echo command needs the \n ...)
Al
David Akins wrote in message <[EMAIL PROTECTED]>...
>How do I send an ATDT command to the modem from the command line?
>
>Al I want to do is write a script to page me when certain things
>happen. I've tried chat, but it seems like chat only works when
>called from another program. It seems like this should work:
>
>chat '' ATDT123-4567,,,,911#
>
>but nothing happoens.
>
>Minicom will work as long as you run it from a logged-in shell. I
>guess minicom tried to do screen writes that get messed up when run
>froma scheuler in thebackground.
>
>Anybody know what I can do? Please be specific.
------------------------------
From: [EMAIL PROTECTED] (Khoo Yit Phang)
Subject: Win95 -> linux -> internet
Date: Fri, 13 Aug 1999 10:49:37 GMT
Hello, i'm new to linux and i'm using RedHat 6.0 and win95.
Well, i've managed to set up a network between my computers, setup
linux to do most of what i want it to do (albeit not too securely
yet).
My next quest is to make linux a gateway to the internet through a 56K
modem. (to do web browsing, email, icq, speakfreely etc...)
What do i use to do this? Routing? IPMasq? IPChain? Firewall?
IPIP? SOCKS?
I'm quite confused with all these ways of connecting networks, so
please help me sort out this confusion, as well as give a a rundown on
their uses.
Thank you.
------------------------------
From: "ArTec - Vincent MAURY" <[EMAIL PROTECTED]>
Subject: telnet to slow from W95
Date: 13 Aug 1999 10:56:26 GMT
1st question
I've to wait more than 30secs before I can telnet a Linux box from W95
(WNT4)
Do you know how to speed this ?
2nd
I seem to have the same problem with mail daemon ....
------------------------------
From: "David Travers" <[EMAIL PROTECTED]>
Crossposted-To: comp.os.linux.hardware,comp.os.linux.setup
Subject: Serial Cards for Linux for PPP Server in the UK ?
Date: Fri, 13 Aug 1999 12:05:45 +0100
Does anyone know of cheap but reliable multi-port serial cards (4 ports or
more) that can be used with external modems to create a PPP server (ISA or
PCI).
I am based in the UK, so any contact numbers etc would be useful.
If you have prices, web links, technical info etc that would be great.
We have 4 telephone numbers on a hung-group and I want to setup a Linux box
as a PPP server so that users can dial-in and access the company's network
for e-mail etc.
If you could please reply to my e-mail address I would be most grateful.
Thanks in advance
David Travers
------------------------------
From: DHobbs <[EMAIL PROTECTED]>
Crossposted-To: alt.linux,alt.os.linux
Subject: Re: ipchains Newbie Q
Date: Thu, 12 Aug 1999 09:09:12 -0400
David Eno wrote:
>
> I want to share a dialup connection (ppp0) on my Mandrake 6.0 machine with a
> Win98 box that's logged in via Samba.
>
> Do I use ipchains to do this? Where can I get information supplemental to
> the man pages?
http://metalab.unc.edu/mdw/HOWTO/mini/IP-Masquerade.html
Dan
------------------------------
From: Lindoze 2000 <[EMAIL PROTECTED]>
Subject: Re: My first Network install - N
Date: Fri, 13 Aug 1999 01:28:02 -0400
QuestionExchange wrote:
>
> > I need advices on how to configure a server/router using my new
> > ASDL internet connection. ( ..... Long term objective is to
> > make this router my network server with Linux OS to serve my
> > current machine (B) and a future machine (machine name: X). ...
> > Note that I also plan to install HTTP server, Samba, File
> > server, and more ) Short term objective (if realistic) is to
> > set up a machine (A) as a server (gateway) which will also act
> > as a firewall for my second machine (B). I plan to connect
> > these machines through NICs with twisted pair RJ45. Machine
> > (A) config: 486SX66 - 8 Meg ram hd 1 gig - 2 network cards----
> > 1> Dlink PNP model (?) --- 2-> 3Com model 3c503 512k Ram on
> > Graphic card - VGA/EGA Trident 9000 I plan to use my ADSL
> > connection (connected to my 3com 3c503) to install RadHat by
> > ftp using bootnet.img diskette. - Is it faisable ? - If not,
> > what other solution I have ? - Is this hardare sufficient to
> > support XFree86/Xwindows installation - Is redhat a good choice
> > for server setup Any suggestions, comments and questions are
> > more than welcome. Sent via Deja.com http://www.deja.com/
> > Share what you know. Learn what you don't.
>
> I did nearly the exact same thing with a low end Pentium,
> except with Debian (http://www.debian.org) instead of RedHat
> because (IMHO) it is easier to install via FTP and is all
> around more bug-free, stable, and mature distribution. It
> probably will work for RedHat, too, but you might want to give
> Debian a shot. There's no way that you can realistically run X
> with 8 MB of RAM. My server machine (a Pentium 150 w/ 32 MB of
> RAM and 3 GB of disk with the services you describe running)
> handles the job fine..but I'd recommend moving to 32 MB of RAM
> on your system and making at least 32 MB of swap, if you plan
> to run all of those services. Honestly, I think you'd be
> disappointed with X's performance even then, unless you ran an
> ultra-lightweight window manager (like fvwm2 or blackbox).
> Whichever distribution you choose, read the IP-Masquerading
> mini-HOWTO (available from the Linux Documentation Project at
> http://metalab.unc.edu/LDP). It helped me a great deal and
> covers setting up the linux server and any linux or windows
> clients. What you are trying to do is a perfect example of why
> Linux is a far superior niche os than Windows NT. It would take
> $900 and the horsepower of a $2000 PC to do with NT Server what
> you can do with Linux on an 'obsolete' machine.
>
adside from the obvious inefficences of WinNT/Win95/98, M$ Win in gen.
is
a lot more hardware intensive because of what it does.
windows was built with dummies in mind. they assUme that the guy sitting
in front of the computer is more stupid than the computer itself. so
therefore
the progs. have to do lots of guessing and searchiung.
whereas linux assumes that you know what you are doing, and if you dont,
it doesn't care.
> --
> This answer is courtesy of QuestionExchange.com
>
>http://www.questionexchange.com/servlet1/showUsenetGuest?ans_id=2512&cus_id=USENET&qtn_id=1574
--
Thank you for your valuable input. Your useful answers will benifit
other users as well.
You are Linux!
########################################################
## ##
## My Experiment ##
## http://www.FusionPlant.com ##
## ##
########################################################
------------------------------
From: David Crooke <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Subject: Masquerading - Re: LinkSys Etherfast 10/100 (I know...)
Date: Fri, 13 Aug 1999 05:28:28 GMT
Brian Whitman wrote:
>
> I've seen all the other posts concerning this card, but my problem is
> *special* :)
>
> I have a Linksys Etherfast 10/100 NIC (PCI). I have compiled and
> insmodded the tulip.o that comes with the card, and it recognizes it
> wonderfully upon boot as eth0. Now, my problem is, I can't do anything
> with it.
>
> What I know:
>
> * I can ping "myself": 192.168.0.1
> * From the other system on my network (via crossover cable, a Win98), I
> can ping it fine.
> * I should be connecting to the inernet via Win98's DHCP / "Internet
> Connection Sharing."
> * In linuxconf I have IP address set to 192.168.0.1, driver set to
> tulip, interface set to eth0, and netmask to 255.255.255.0... (I have
> also tried selectively eliminating various parameters to no avail)
> * I cannot ping to anywhere from linux but myself.
> * ifconfig sees the card fine with the IP address set up.
>
> So, what am I doing wrong? All I'd like to do is to be able to use the
> other computer's net connection via DHCP...
>
Okay, I think there are a few things jumbled here:
1. If ping works then the card is working fine - this is a sofware
configuration (not driver or hardware) issue
2. DHCP is a protocol used for one server to automatically assign
addresses to all the other machines on a subnet. If you want to use
Win98 as a DHCP server and have your Linux machine get an address via
DHCP, you need to run a DHCP client (like dhcpcd) on the Linux box. I'd
suggest however that you *don't* do that, and just stick to using
192.168.0.1 as a fixed address.
3. By "Internet Connection Sharing" I think you mean having the Win98 PC
act as a masquerading firewall. I don't know if the software you have
will do this (AFAIK it isn't a standard feature of Win98, and WinGate is
the most popular add-on that does it). For this to work, you need two
things:
- have the Win98 machine set up for IP masquerading
- tell the Linux machine to use the Win98 machine as its default router
(gateway), like this:
/sbin/route add default gw 192.168.0.2 eth0
Long term: I would give due consideration to swapping them round,
putting the internet connection on the Linux box and using it as a
masquerading router. Linux supports this very well, with built in
masquerading and firewall capabilties.
Dave
--
David Crooke, Austin TX, USA. +1 (512) 656 6102
"Open source software - with no walls and fences, who needs Windows
and Gates?"
------------------------------
From: Lederhaas Horst <[EMAIL PROTECTED]>
Subject: Sendmail Problems
Date: Fri, 13 Aug 1999 09:42:23 +0200
i have some big problems with sendmail
1.) how can i configure sendmail that it store all incoming and outgoing
mail to a extra folder?
2.) how can i configure sendmail to forward all mails with unqualified
usernames and domains to the postmaster?
3.) how can i configure sendmail when somebody send a mail to
"[EMAIL PROTECTED]"
that it stored to "lederhaas.horst" and forward it to "[EMAIL PROTECTED]" ?
greetings
Horst Lederhaas
------------------------------
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End of Linux-Networking Digest
******************************
