SNAT hangs system in SMP mode (kernel 2.4.21)

SNAT hangs system in SMP mode (kernel 2.4.21)

[Diederick van Dijk]

Hi,

Yesterday I upgraded my system from one Pentium III 450Mhz processor to 
two Pentium III 450 processors. This system is my gateway to the internet.
After upgrading I recompiled the kernel (2.4.21) into SMP mode.
Unfortunately this wasn't a success. After a few minutes my system hung. 
After some searching I'm realy sure that my SNAT rules are the problem. If 
I get my email on an other PC with no other IP activity on my network my 
gateway immediately hung. Retrieving email uses a SNAT rule.
So I recompiled my kernel uni-processor and the problem was over.
Is this a known problem ? How do I fix this (MASQ rules are not the 
solution) ? If someone needs additional information please ask.

System specs :

- 2 x Pentium 450 Mhz
- 256 MB SDRAM
- kernel 2.4.21 (not the stock Mandrake kernel)
- iptables 1.2.7a
- Mandrake 9.1
- 9x SNAT rules

Thanks in advance,

Diederick   

RE: SNAT hangs system in SMP mode (kernel 2.4.21)

[Waldecir Loureiro dos Santos Filho]

I get this problem too, with Kernel-2.4.21, now I back to orignal kernel of
RH and no more problems

Some budy know if 2.4.21 have a problem with iptables ? ? ?



-----Original Message-----
From: netfilter-admin@lists.netfilter.org
[mailto:netfilter-admin@lists.netfilter.org]On Behalf Of Diederick van Dijk
Sent: segunda-feira, 21 de julho de 2003 05:19
To: netfilter@lists.netfilter.org
Subject: SNAT hangs system in SMP mode (kernel 2.4.21)

Hi,

Yesterday I upgraded my system from one Pentium III 450Mhz processor to
two Pentium III 450 processors. This system is my gateway to the internet.
After upgrading I recompiled the kernel (2.4.21) into SMP mode.
Unfortunately this wasn't a success. After a few minutes my system hung.
After some searching I'm realy sure that my SNAT rules are the problem. If
I get my email on an other PC with no other IP activity on my network my
gateway immediately hung. Retrieving email uses a SNAT rule.
So I recompiled my kernel uni-processor and the problem was over.
Is this a known problem ? How do I fix this (MASQ rules are not the
solution) ? If someone needs additional information please ask.

System specs :

- 2 x Pentium 450 Mhz
- 256 MB SDRAM
- kernel 2.4.21 (not the stock Mandrake kernel)
- iptables 1.2.7a
- Mandrake 9.1
- 9x SNAT rules

Thanks in advance,

Diederick



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RE: SNAT hangs system in SMP mode (kernel 2.4.21)

[Martin Josefsson]

On Mon, 2003-07-21 at 14:38, Waldecir Loureiro dos Santos Filho wrote:
> I get this problem too, with Kernel-2.4.21, now I back to orignal kernel of
> RH and no more problems
> 
> Some budy know if 2.4.21 have a problem with iptables ? ? ?

I havn't seen this problem. Can you reproduce it at will?
If so, could you guys please try the nmi watchdog?

Add nmi_watchdog=1 to the kernel commandline in the bootloader.

Boot with that and wait a few seconds after the hang and see if it
prints out anything. Write that down (using a serial console is
recommended) and run it through ksymoops and post the output to the
netfilter-devel list.

-- 
/Martin

Re: SNAT hangs system in SMP mode (kernel 2.4.21)

[Diederick van Dijk]

On Tuesday 22 July 2003 20:29, Martin Josefsson wrote:
> On Mon, 2003-07-21 at 14:38, Waldecir Loureiro dos Santos Filho wrote:
> > I get this problem too, with Kernel-2.4.21, now I back to orignal kernel
> > of RH and no more problems
> >
> > Some budy know if 2.4.21 have a problem with iptables ? ? ?
>
> I havn't seen this problem. Can you reproduce it at will?
> If so, could you guys please try the nmi watchdog?
>
> Add nmi_watchdog=1 to the kernel commandline in the bootloader.
>
> Boot with that and wait a few seconds after the hang and see if it
> prints out anything. Write that down (using a serial console is
> recommended) and run it through ksymoops and post the output to the
> netfilter-devel list.

Hi,

Yes, I can reproduce this problem at will. I shall try the nmi watchdog.
But it has to wait until Saturday because I'm very busy right know and need my 
internet connection (The machine is my internet gateway).

Diederick