Linux-Networking Digest #406, Volume #12 Sun, 29 Aug 99 20:13:37 EDT
Contents:
Re: Can an ISP detect masquerading? (Tom Verbeure)
Re: NFS and GNU Linker producing corrupted executables (RHL 2.2.5-15/2.2.11 and AIX
4.2.1) ("Martin Knoblauch")
Firewalling Question (Patrick Finnegan)
Re: Can an ISP detect masquerading? (Tom Verbeure)
Re: new linux box added to network can't access internet (Patrick Finnegan)
Re: looking for a webhosting administration software for linux (Wesley Miaw)
Re: DCC probs with ip_masq. (MBr)
Re: VMware - wow! (Martin Drautzburg)
Re: Masquarada and X (Dale Pontius)
Re: Problems with ISDN connection (Chris Mahmood)
Re: What on earth is 'bing'? (Tiaan van Aardt)
Re: What on earth is 'bing'? (Tiaan van Aardt)
DHCP, SMTP, and Linux problems... ("Brad")
Re: Samba Setup ([EMAIL PROTECTED])
----------------------------------------------------------------------------
From: Tom Verbeure <[EMAIL PROTECTED]>
Subject: Re: Can an ISP detect masquerading?
Date: Sun, 29 Aug 1999 21:52:17 GMT
Bernd Eckenfels wrote:
>
> Tom Verbeure <[EMAIL PROTECTED]> wrote:
> > But I just want to know: HOW can they detect this?
>
> well.. u can guess it if you see a lot of outgoing connections originating
> from ports in the usual masquerading range (61000-65000). But u can change
> that port.
>
> Greetings
> Bernd
Hello Bernd,
I checked in the kernel source code and found the constants in
/usr/src/linux/include/net/ip_masq.h. Interesting stuff.
Now I am wondering in what way I can change them: Putting them in any
place above 32k would probably be possible without to much trouble, but
I suppose that putting them below this border will result in trouble,
right?
The best solution to hide masquerading completely would probably be to
put it there were other ports are located.
Maybe there is some variable in the Linux kernel the sets the 32k
border. By lowering this to, say, 28k and putting the PORT_MASQ_BEGIN to
28k, the masquerading would be completely undetectable, right?
Regards,
Tom
------------------------------
From: "Martin Knoblauch" <[EMAIL PROTECTED]>
Crossposted-To:
comp.os.linux.setup,comp.os.linux.development,comp.os.linux.development.kernel,comp.unix.aix
Subject: Re: NFS and GNU Linker producing corrupted executables (RHL 2.2.5-15/2.2.11
and AIX 4.2.1)
Date: Sun, 29 Aug 1999 14:30:43 +0200
David Elder wrote in message
<[EMAIL PROTECTED]>...
>
>3) Results:
>
> a) All of the .o files compiled to either the local
> or NFS file systems compare as Identical.
>
> b) Executables that are written on the NFS file system
> do NOT work. They generate an error:
> Memory Fault (core dump).
>
first thing to check would be that the lock demon is running (and working
to specs :-( I have seen this on other system combinations and lockd was
usually involved.
Martin
--
============================================================
Martin Knoblauch
Compaq Computer EMEA BV
E-Mail: [EMAIL PROTECTED]
Std.Disclaimer: Not speaking for COMPAQ in any form on this medium
------------------------------
From: Patrick Finnegan <[EMAIL PROTECTED]>
Subject: Firewalling Question
Date: Sun, 29 Aug 1999 16:28:41 -0500
I have set up an IPmasq firewall and am wondering if there is a way i
can redirect a port on the firewall machine to a port on a machine that
is behind the IPmasq firewall. Thanks much!
Patrick Finnegan
------------------------------
From: Tom Verbeure <[EMAIL PROTECTED]>
Subject: Re: Can an ISP detect masquerading?
Date: Sun, 29 Aug 1999 21:30:10 GMT
> > Well. The point is that they are already doing regular scans of the
> > network (not constantly) to check for subscribers who are running a
> > server. The contract with the ISP explicitly forbids running servers,
>
> I'm sorry, but this is just inane. What is defined as a server? Does
> this mean that in.telnetd is a contract violation, because it listens on
> ports and accepts remote connections? What about inetd? If you can
> finger a site, you're essentially connecting to a server. Even
> Windows computers run "servers". Who *are* these people?
All these definitions are, indeed, being regarded by them as a server
and may not be used over the computer. And yes, I have closed don't
inetd and everything. :-(
> I went to the mat with my ISP over the same issue. After a brief
> squabble with a front-line management type over whether or not a
> masquerading "server" was a contract violation, they agreed that
> masquerading "services" could be run without issue (just as long as it
> wasn't a "server" that was running them..?).
IP masquerading is not *explicitly* forbidden in de contract, but
proxies etc. are... In fact, their way of reasoning is simple: one
customer = one payer. So, if you connect a network to the cable modem,
multiple persons can use the line at the same time, which if being
regarded as a loss of revenue.
The only way to enforce this, is to be able to scan this. With a
firewall or a proxie, you hide everything so they can not detect the
"multiple users abuse".
They also limit the bandwidth to 37 kbyte/s, but that's acceptable for
me...
(Thanks for all answers so far!)
Tom
------------------------------
From: Patrick Finnegan <[EMAIL PROTECTED]>
Subject: Re: new linux box added to network can't access internet
Date: Sun, 29 Aug 1999 16:32:19 -0500
"Christopher J. Vogt" wrote:
> I have an NT machine as a multi-homed gateway to the internet. My LAN has
> been up and running fine for years running through the NT box which runs a proxy
> server and connects to the internet via a cable modem.
>
> I just got a linux box running redhat 6, stuck it on my lan and configured it.
> I can ping every machine on my lan just fine and vice versa. I can ping the
> NIC on the NT box that connects to the internet just fine, but I cannot ping
> anywhere else. Also, strangely, I cannot do a traceroute to the NIC card
> on the NT box that connects to the internet. Anybody have any ideas? Thanks.
Check that you have properly set up the default gateway to point to the local NIC
on the NT box.
------------------------------
From: [EMAIL PROTECTED] (Wesley Miaw)
Crossposted-To:
alt.www.webmaster,comp.infosystems.www.misc,comp.infosystems.www.servers.misc,comp.infosystems.www.servers.unix
Subject: Re: looking for a webhosting administration software for linux
Date: Sun, 29 Aug 1999 14:56:53 -0700
In article <7qbmdh$u28$[EMAIL PROTECTED]>, "Ralf Huelsmann"
<[EMAIL PROTECTED]> wrote:
>i�m looking for software to do the administration for a linux webserver.
>
>we use suse 6.2 and apache
I would say you already have almost all the software you need. Billing
isn't really server administration.
>- set up new domains / users... (virtual host , hosts, adduser, ftp,
>directories, quota)
Use YaST for creating/deleting/modifying new users and you can
automatically setup what should be in a new user's directory by modifying
the contents of /etc/skel.
I don't see why ftp is a problem to set up. By default new users are
allowed to FTP into their home directories. So, for people with virtual
domains, set their home directories to their virtual domain directories
with YaST. To block people, add their username to /etc/ftpusers. For
anonymous FTP, it's probably already set up. I use proftpd, so editing
/etc/proftpd.conf would let me turn off anonymous FTP or do more advanced
stuff. To see what FTP daemon you're running, look in /etc/inetd.conf.
edquota will let you set user quotas. See the manpage on edquota. Use
quotaon and quotaoff to turn quotas on and off. And of course, quota is
used to display quota data.
>- kill old users
YaST.
>- help with billing (billing for fixed, premiumservices and traffic)
Not sure what to recommend here. An ISP I've talked with developed their
own internal system. I wrote a traffic monitoring script using tcpdump and
Perl to batch process the dump (static IP addresses) for another ISP. Not
sure what they planned to do with the dump, but at least there was a
report.
Anyway, I'm sure a search at any of the engines would turn up a bunch of
resources. I found http://www.westnet.com/providers/ which lists Freeside,
which is distributed under the GPL. UTA, also listed on that page, looks
nice but is kinda expensive. The other one I found is Internet Billing
Software at http://winsoft.net.au/winsoft/ibs/demo.htm.
Hope this helps,
--
Wesley Miaw [EMAIL PROTECTED]
World of Artists Internet Services http://www.woais.com/
2110 Kittredge Street #112 Tel: 510-548-8819
Berkeley, CA 94704 FAX: 510-548-1718
------------------------------
From: MBr <[EMAIL PROTECTED]>
Subject: Re: DCC probs with ip_masq.
Date: Mon, 30 Aug 1999 00:17:55 +0200
Jeff Japes wrote:
> Hi
>
> I'm having probs dccing on irc with my computer that connects to the
> net via my linux box using ip masq.
> I have the ip_masq_irc module loaded, with the required ports option,
> but dcc's are still failing to get through.
>
> The details..
> Using RH6, kernel 2.2.11
>
I've got exactly the same problem, using SuSE 6.1 and kernel 2.2.7,
2.2.9-2.2.11
Manuel Beunder
>
> script used to start the masq stuff...
>
> modprobe ip_masq_irc ports=6667,6666,6665,9000
> modprobe ip_masq_ftp
> modprobe ip_masq_raudio
> ipchains -F
> ipchains -P forward DENY
> ipchains -A forward -s 192.168.2.2/32 -j MASQ
> echo 1 > /proc/sys/net/ipv4/ip_forward
>
> Can anyone give any ideas?
>
> Thanks..
>
> Jeff Japes
> Jeff (at) wylm . demon . co . uk
------------------------------
From: Martin Drautzburg <[EMAIL PROTECTED]>
Crossposted-To: athome.users-unix,comp.os.linux.misc,comp.os.linux.setup
Subject: Re: VMware - wow!
Date: 29 Aug 1999 22:49:03 +0200
Jason Pell <[EMAIL PROTECTED]> writes:
> I realise what you are saying about it not being truly a virtual
> machine, but the chance to have Windows 95 running where it belongs
> (in an X window) is really nice.
Yeah I got off on this one too: iconifying Win98, that�s really some
experience !
--
In a world without walls and fences, who needs windows and gates ?
-- Martin
------------------------------
From: [EMAIL PROTECTED] (Dale Pontius)
Subject: Re: Masquarada and X
Date: Sun, 29 Aug 1999 13:58:21 -03-59
In article <[EMAIL PROTECTED]>,
Krzysztof Bujak <[EMAIL PROTECTED]> writes:
> I need some help from you gurus.
> What to do to be able use remote x-server throug masquarqde?
> PLease help
>
It may be possible to run DXPC on the firewall. The Xclient
directs its display to firewall/masq machine, where dxpc
catches it. Then dxpc sends its display to your local machine.
Dale Pontius
DEPontius AT usa DOT net
------------------------------
From: Chris Mahmood <[EMAIL PROTECTED]>
Crossposted-To: alt.os.linux,alt.linux
Subject: Re: Problems with ISDN connection
Date: 29 Aug 1999 14:41:05 -0700
The first connection listed is using PAP, the second isn't.
-ckm
------------------------------
From: Tiaan van Aardt <"tva"@cellpt.(nospam).co.za>
Crossposted-To: comp.os.linux.misc,comp.protocols.tcp-ip
Subject: Re: What on earth is 'bing'?
Date: Mon, 30 Aug 1999 01:04:43 +0200
Reply-To: [EMAIL PROTECTED]
Hi Ramon,
> There is a very similar tool called "traceroute+bing" that can
> trace the list of routers and also give you the BW at every hop.
> I have been unable to make that tool work (the 'bing' part
> always says "unknown"), that's why I am looking for a standalone
> bing.
Also look for a tool called VisualRoute. It's a tool that runs under a
JavaVM (works very well if you have IE5 installed) and it can do traces
like the ones you are looking for. I also highlights any problem areas
on the links and gives a graphical plot of latency accross the entire
route (per hop).
Good luck,
-Tiaan.
______________________________________________________________________
Systems Engineer | For the time of your life: http://www.time.za.net
Cellpoint Systems & | GSM Technology for Positioning and Telematics
Wasp International | Unix/NT/Cisco admin & C++/Delphi development
------------------------------
From: Tiaan van Aardt <"tva"@cellpt.(nospam).co.za>
Crossposted-To: comp.os.linux.misc,comp.protocols.tcp-ip
Subject: Re: What on earth is 'bing'?
Date: Mon, 30 Aug 1999 01:05:20 +0200
Reply-To: [EMAIL PROTECTED]
Hi Ramon,
> There is a very similar tool called "traceroute+bing" that can
> trace the list of routers and also give you the BW at every hop.
> I have been unable to make that tool work (the 'bing' part
> always says "unknown"), that's why I am looking for a standalone
> bing.
Also look for a tool called VisualRoute. It's a tool that runs under a
JavaVM (works very well if you have IE5 installed) and it can do traces
like the ones you are looking for. I also highlights any problem areas
on the links and gives a graphical plot of latency accross the entire
route (per hop).
Good luck,
-Tiaan.
______________________________________________________________________
Systems Engineer | For the time of your life: http://www.time.za.net
Cellpoint Systems & | GSM Technology for Positioning and Telematics
Wasp International | Unix/NT/Cisco admin & C++/Delphi development
------------------------------
From: "Brad" <[EMAIL PROTECTED]>
Subject: DHCP, SMTP, and Linux problems...
Date: Sun, 29 Aug 1999 18:58:54 -0400
A friend of mine has recently switched from PPP to ADSL with DHCP.
We are using ipfwadm on a linux box for IP masquerading with two win95
machines over ethernet. But since switching to ADSL and DHCP (for the
ADSL, not the LAN), we can no longer send e-mail longer than a few lines:
any SMTP server we use hangs (I think in the DATA part of the HELO
exchange).
We've tried several different clients (on the Linux box and the Win95
boxes), but all hang or timeout. Telneting into the SMTP port directly
_does_ work, however. Things will also work when we start a PPP session.
Hrmm, in trying to post this, we found that NNTP also does not work. :-/
HTTP, ICQ, FTP, etc, work fine, though.
Any ideas, suggestions? The ISP is Bellsouth.net. The ADSL modem is an
Alcatel 1000. We're using NE2000-clone NIC's. ipfwadm is 2.3.0 dhcpcd is
0.70-5 We're using Debian 2.1 with a 2.0.36 kernel. We're also using Win95
B and C.
-=-=-=-
The routing and ifconfig information with ADSL and no PPP:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
localhost * 255.255.255.255 UH 0 0 0 lo
localnet * 255.255.255.0 U 0 0 1 eth0
216.78.148.0 * 255.255.252.0 U 0 0 1 eth1
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
lo Link encap:Local Loopback
inet addr:127.0.0.1 Bcast:127.255.255.255 Mask:255.0.0.0
UP BROADCAST LOOPBACK RUNNING MTU:3584 Metric:1
RX packets:2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
eth0 Link encap:Ethernet HWaddr 00:00:B4:23:C6:27
inet addr:10.0.0.1 Bcast:10.0.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
Interrupt:12 Base address:0x300
eth1 Link encap:Ethernet HWaddr 00:00:B4:23:B9:5A
inet addr:216.78.148.144 Bcast:216.78.151.255 Mask:255.255.252.0
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:20 errors:0 dropped:0 overruns:0 frame:0
TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
Interrupt:5 Base address:0x260
-=-=-=-
With PPP and ADSL:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
localhost * 255.255.255.255 UH 0 0 0 lo
209.215.218.7 * 255.255.255.255 UH 0 0 0 ppp0
localnet * 255.255.255.0 U 0 0 2 eth0
216.78.148.0 * 255.255.252.0 U 0 0 1 eth1
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
default 209.215.218.7 0.0.0.0 UG 0 0 0 ppp0
lo Link encap:Local Loopback
inet addr:127.0.0.1 Bcast:127.255.255.255 Mask:255.0.0.0
UP BROADCAST LOOPBACK RUNNING MTU:3584 Metric:1
RX packets:2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
eth0 Link encap:Ethernet HWaddr 00:00:B4:23:C6:27
inet addr:10.0.0.1 Bcast:10.0.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:58 errors:0 dropped:0 overruns:0 frame:0
TX packets:62 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
Interrupt:12 Base address:0x300
eth1 Link encap:Ethernet HWaddr 00:00:B4:23:B9:5A
inet addr:216.78.148.144 Bcast:216.78.151.255 Mask:255.255.252.0
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:73 errors:0 dropped:0 overruns:0 frame:0
TX packets:46 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
Interrupt:5 Base address:0x260
ppp0 Link encap:Point-to-Point Protocol
inet addr:209.214.180.54 P-t-P:209.215.218.7 Mask:255.255.255.0
UP POINTOPOINT RUNNING MTU:1500 Metric:1
RX packets:9 errors:0 dropped:0 overruns:0 frame:0
TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
Collisions:0
Memory:1447038-1447c04
-=-=-
We appreciate your help!
------------------------------
From: [EMAIL PROTECTED]
Subject: Re: Samba Setup
Date: Sun, 29 Aug 1999 22:56:23 GMT
I tried it out, and this is what I get...which is basically the same as
when I start up with the error. "eth0" does not appear when I type
ifconfig. Tulip driver is the best it can use...no specific one. I
actually meant the "Control Panel" in the Utilities section of X that
only root has. It has Networking as one of the options.
[root]# ifconfig eth0 up 192.168.1.3
Unable to handle kernel paging request at virtual address 20000000
current->tss.cr3 = 06864000, %cr3 = 06864000
*pde = 00000000
Oops : 0000
CPU : 0
EIP : 0010 : [<c01ac6c7>]
EFLAGS : 00010246
eax: fffffff8 ebx: 20000000
::continue::
Process ifconfig (pid: 724, process nr: 6,stackpage = c5f0f000)
::continue::
Segmentation fault
[root]#
Any clues on what this problem is and/or how to fix it?
Tom
In article <7q7arb$cri$[EMAIL PROTECTED]>,
[EMAIL PROTECTED] wrote:
> Give up with the crossover cable, and get a hub and some Cat-5
> cabling. It makes things much easier.
>
> To verify that your network card is indeed working, type "ifconfig".
> You should see a listing for device lo, and device eth0. If you don't
> see eth0 listed, and have the kernel compiled to support your network
> card, type the following : "ifconfig eth0 up ipaddress" (substituting
> the IP address you want the card to have for the word). This will
> enable your network card.
>
> I'll assume the control panel you mean is linuxconf. I use Slackware
> 4.0, so I don't have that. I did use RH 6.0 for a while though. Do
> everything you've been doing in there, but don't make the card active
> at boot time. After boot-up, use the above command to activate it.
> See if that works.
>
> Last resort:
>
> Get X-Windows (or KDE, or GNOME) running, and do the kernel
> recompilation again "make xconfig". See if you can find a different
> driver than the tulip driver, preferably one that exactly matches your
> card. I recommend checking Donald Becker's homepage for a better
> driver anyway (if it's not included in RH 6.0 list of network
> drivers). http://cesdis.gsfc.nasa.gov/linux/misc/100mbs.html#100baseT
> Check all of the hyperlinks until you find the exact model of your
card.
>
> Hope this helped.
>
> Peace,
> Joe
>
> In article <7q751d$9f8$[EMAIL PROTECTED]>,
> [EMAIL PROTECTED] wrote:
> > I use Red Hat 6 with the CNET Pro120B 10/100 (tulip) network card.
> When
> > I first installed Linux w/ network support, it hanged (and spit out
a
> > bunch of numbers) during boot up. I couldn't get into login, so I
> > reinstalled w/o networking. I recompiled the kernel to support my
> > network card because it wouldn't boot properly as a module. It
worked
> > fine, but all this was before I got my crossover cable to try to
> > connect it with my win98.
> >
> > I used the Control Panel to try to enble networking again (entering
> > 192.168.1.1 as IP, 255.255.255.0 as netmask, and enable at boot),
but
> > when I restart, I get the same hanging (spit out) as before. I go
back
> > in without networking (another kernel) and undo what I did. I
changed
> > the smb.conf (WORKGROUP and Windows logon) and restarted it. It
boots,
> > but without my "enable at boot", eth0 is never initialized. So when
I
> > turn on Windows, I get "domain server not valid...". At this point,
I
> > have not a single clue as to what I should try. Any, and I mean
_ANY_,
> > suggestions would help. I'm planning to reinstall Red Hat w/
> > networking, but knowing what happened earlier, it will probably hang
> > again.
> >
> > Extra Info:
> > -Red Hat install detects a tulip network card, but it continues to
> hang
> > during boot.
> > -With the recompiled kernel, it detects the network card perfectly,
> > assigning ioports/irqs, but will not initilize eth0.
> > -I _had_ eth0 and the new kernel working together, but when I
changed
> > the networking settings in the Control Panel, it stopped. Now, even
> > after undoing my changes, it won't work and will only boot with eth0
> > disabled during boot.
> >
> > *sorry for such a long read
> >
> > Sent via Deja.com http://www.deja.com/
> > Share what you know. Learn what you don't.
> >
>
> Sent via Deja.com http://www.deja.com/
> Share what you know. Learn what you don't.
>
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
------------------------------
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End of Linux-Networking Digest
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