2000-10-31 04:14:00

by Carl Perry

[permalink] [raw]
Subject: Is IPv4 totally broken in 2.4-test

I have test9 running in an original Athlon 500, a PII 300, and a K6-2/400. All
of them are experiencing the same problems with networking. I confimred that
this is not happening to just my, as my buddy in a far away (California) land is
experiencing the same thing. I cannot connect to ubid.com, landsend.com,
etrade.com, travelocity.com, and a slew of others. I'm not sure if this is
because all of those sites are going "Wow! His IP stack conforms to _STANDARDS_
- it must be fake" or what. However, it's really starting to get on my nerves.

All of the above boxes are based on SuSE 6.4. Using the latest modutils,
binutils 2.10, and egcs-1.1.2 (Which I think is still compiler gratas) My
buddy's box is a Mandrake 7.1 box. I know he was using gcc-2.95.2 and an old
binutils, but he has changed to egcs-1.1.2 and a newer binutils. He's still
having the same problem. I pretty sure it's not an iptables issue, since I
believe that he has iptables off. I also tried no tables on my K6-2 box with
the same effects.

Is anyone else experiencing these problems? Does anyone know if certain
firewalls don't like 2.4 with a passion? Even better, does anyone know how to
fix it?

BTW: I have narrowed this down to a 2.4 problem. If I load 2.2 on any of those
machines on the same ISP it doesn't work.

Any ideas?
--
-Carl Perry
[email protected]

"Real programmers don't draw flowcharts. Flowcharts are, after
all, the illiterate's form of documentation. Cavemen drew
flowcharts; look how much good it did them."
-Fortune (The App, not the Magazine)


2000-10-31 04:19:11

by David Miller

[permalink] [raw]
Subject: Re: Is IPv4 totally broken in 2.4-test


echo "0" >/proc/sys/net/ipv4/tcp_ecn

Or don't enable CONFIG_INET_ECN in your kernel configuration.

Later,
David S. Miller
[email protected]

2000-10-31 04:24:21

by Carl Perry

[permalink] [raw]
Subject: Re: Is IPv4 totally broken in 2.4-test

Duh. And here I was thinking that was a good thing. That did it. What exactly
does "Explicit Congestion Notification" do? I figured it was going to put a
message in syslog if the wire is full and packets were being dropped. There
weren't any docs in menuconfig - so I figured "what the hey?". Boy - I was
wrong. Thanks for the quick response. I haven't even gotten the post back yet.

"David S. Miller" wrote:
>
> echo "0" >/proc/sys/net/ipv4/tcp_ecn
>
> Or don't enable CONFIG_INET_ECN in your kernel configuration.
>
> Later,
> David S. Miller
> [email protected]

--
-Carl Perry
[email protected]

"Real programmers don't draw flowcharts. Flowcharts are, after
all, the illiterate's form of documentation. Cavemen drew
flowcharts; look how much good it did them."
-Fortune (The App, not the Magazine)

2000-10-31 04:26:21

by Mohammad A. Haque

[permalink] [raw]
Subject: Re: Is IPv4 totally broken in 2.4-test

if [ -f /proc/sys/net/ipv4/tcp_ecn ]
then
echo "0" >/proc/sys/net/ipv4/tcp_ecn
fi

or dont compile with ECN support int he kernel.

Carl Perry wrote:
>
> I have test9 running in an original Athlon 500, a PII 300, and a K6-2/400. All
> of them are experiencing the same problems with networking. I confimred that
> this is not happening to just my, as my buddy in a far away (California) land is
> experiencing the same thing. I cannot connect to ubid.com, landsend.com,
> etrade.com, travelocity.com, and a slew of others. I'm not sure if this is
> because all of those sites are going "Wow! His IP stack conforms to _STANDARDS_
> - it must be fake" or what. However, it's really starting to get on my nerves.
>
> All of the above boxes are based on SuSE 6.4. Using the latest modutils,
> binutils 2.10, and egcs-1.1.2 (Which I think is still compiler gratas) My
> buddy's box is a Mandrake 7.1 box. I know he was using gcc-2.95.2 and an old
> binutils, but he has changed to egcs-1.1.2 and a newer binutils. He's still
> having the same problem. I pretty sure it's not an iptables issue, since I
> believe that he has iptables off. I also tried no tables on my K6-2 box with
> the same effects.
>
> Is anyone else experiencing these problems? Does anyone know if certain
> firewalls don't like 2.4 with a passion? Even better, does anyone know how to
> fix it?
>
> BTW: I have narrowed this down to a 2.4 problem. If I load 2.2 on any of those
> machines on the same ISP it doesn't work.
>
> Any ideas?
> --
> -Carl Perry
> [email protected]
>
> "Real programmers don't draw flowcharts. Flowcharts are, after
> all, the illiterate's form of documentation. Cavemen drew
> flowcharts; look how much good it did them."
> -Fortune (The App, not the Magazine)
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> Please read the FAQ at http://www.tux.org/lkml/

--

=====================================================================
Mohammad A. Haque http://www.haque.net/
[email protected]

"Alcohol and calculus don't mix. Project Lead
Don't drink and derive." --Unknown http://wm.themes.org/
[email protected]
=====================================================================

2000-10-31 04:31:21

by David Miller

[permalink] [raw]
Subject: Re: Is IPv4 totally broken in 2.4-test

Date: Mon, 30 Oct 2000 23:53:57 -0600
From: Carl Perry <[email protected]>

What exactly does "Explicit Congestion Notification" do?

It's a protocol extension by which routers can tell clients
about the onset of congestion before the routers stops to drop
that client's packets.

Unfortunately, a widely deployed firewall product made by Cisco and
used at most of the large web sites block packets that make use
of ECN. They have fixed the bug, but I honestly don't expect these
sites to install the fix any time soon no matter how much the Cisco
folks tell me that such sites are "likely to".

Later,
David S. Miller
[email protected]

2000-10-31 04:37:02

by Gregory Maxwell

[permalink] [raw]
Subject: Re: Is IPv4 totally broken in 2.4-test

On Mon, Oct 30, 2000 at 11:53:57PM -0600, Carl Perry wrote:
> Duh. And here I was thinking that was a good thing. That did it. What exactly
> does "Explicit Congestion Notification" do? I figured it was going to put a
> message in syslog if the wire is full and packets were being dropped. There
> weren't any docs in menuconfig - so I figured "what the hey?". Boy - I was
> wrong. Thanks for the quick response. I haven't even gotten the post back yet.

The sites are broken. They are running crap firewalls (often Cisco) that
probably haven't been updated (or have no update available), and they see the
(perfectly standards compliant) 'I support ECN' flag, think it must be
something evil and drop the packet silently.

ECN is an important factor for the future scalability of the Internet. It
allows for much smarter methods for congestion control. It's important that
it get implemented, but these crappy firewalls are standing in the way.