conntrack error

conntrack error

[Piotrek Kaczmarek]

Hi,
I encountered the following situation - when there are around 20000 connections
"cat /proc/net/ip_conntrack" doesn't display all connections and outputs
"cat: No space left on device" error. If I patch kernel with POM and 'nth' module
(only patch, don't load the module) the same happens around 17000 connections.
It happenes both with 2.6.9 and 2.6.10 kernels.

Why is it so? Is this matter of memory limit or something else?

Thank you in advantage,

-- 
Piotrek Kaczmarek

Re: conntrack error

[Jason Opperisano]

On Fri, 2005-02-11 at 05:55, Piotrek Kaczmarek wrote:
> Hi,
> I encountered the following situation - when there are around 20000 connections
> "cat /proc/net/ip_conntrack" doesn't display all connections and outputs
> "cat: No space left on device" error. If I patch kernel with POM and 'nth' module
> (only patch, don't load the module) the same happens around 17000 connections.
> It happenes both with 2.6.9 and 2.6.10 kernels.
> 
> Why is it so? Is this matter of memory limit or something else?

what does:

  sysctl net.ipv4.netfilter.ip_conntrack_max

say?  i don't suppose it would be quite that simple, but might as well
start there.

-j

--
"Son, when you participate in sporting events, it's not whether you
 win or lose: it's how drunk you get."
	--The Simpsons

Re: conntrack error

[Piotrek Kaczmarek]

On Fri, Feb 11, 2005 at 01:07:36PM +0000, Jason Opperisano wrote:
> 
> On Fri, 2005-02-11 at 05:55, Piotrek Kaczmarek wrote:
> > Hi,
> > I encountered the following situation - when there are around 20000 connections
> > "cat /proc/net/ip_conntrack" doesn't display all connections and outputs
> > "cat: No space left on device" error. If I patch kernel with POM and 'nth' module
> > (only patch, don't load the module) the same happens around 17000 connections.
> > It happenes both with 2.6.9 and 2.6.10 kernels.
> >
> > Why is it so? Is this matter of memory limit or something else?
> 
> what does:
> 
>   sysctl net.ipv4.netfilter.ip_conntrack_max
> 
> say?  i don't suppose it would be quite that simple, but might as well
> start there.

# sysctl net.ipv4.netfilter.ip_conntrack_max
net.ipv4.netfilter.ip_conntrack_max = 30000

-- 
Piotr Kaczmarek

Re: conntrack error

[Jason Opperisano]

On Fri, Feb 11, 2005 at 04:22:17PM +0100, Piotrek Kaczmarek wrote:
> # sysctl net.ipv4.netfilter.ip_conntrack_max
> net.ipv4.netfilter.ip_conntrack_max = 30000

i assume you set that manually, as i don't think there's an amount
of physical RAM that would result in 30000 on the dot...  speaking of
which--how much physical RAM does this machine have?  you would need 512
MB RAM for ip_conntrack_max to be automatically calculated to 32768,
even though the conntrack table would only really use around 12 MB of
kernel memory.  also--is this machine dedicated solely to firewalling,
or is there something else chewing up your RAM?

-j

--
"I have thought this through. First, I will send Bart the money to
 fly home. Then I will murder him."
        --The Simpsons

Re: conntrack error

[Piotrek Kaczmarek]

On Fri, Feb 11, 2005 at 03:33:22PM +0000, Jason Opperisano wrote:
> On Fri, Feb 11, 2005 at 04:22:17PM +0100, Piotrek Kaczmarek wrote:
> > # sysctl net.ipv4.netfilter.ip_conntrack_max
> > net.ipv4.netfilter.ip_conntrack_max = 30000
> 
> i assume you set that manually, as i don't think there's an amount
> of physical RAM that would result in 30000 on the dot...  speaking of
> which--how much physical RAM does this machine have?  you would need 512
> MB RAM for ip_conntrack_max to be automatically calculated to 32768,
> even though the conntrack table would only really use around 12 MB of
> kernel memory.  also--is this machine dedicated solely to firewalling,
> or is there something else chewing up your RAM?

Yes, I set it by hand, I have 256mb of ram, currently there are ~17000 connections
and 'free' shows 70mb of free memory. That machine is dedicated to routing/firewalling

-- 
Piotr Kaczmarek