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Re: How to have open more than 65k concurrent connections?


From: Joel Jaeggli <joelja () bogus com>
Date: Thu, 14 Oct 2010 09:53:21 -0700

An incoming connection chews up an file descripter but does not require
an ephemeral port.

You can trivially have more that 65k incoming connections on a linux
box, but you've only got 64511 ports per ip  on the box, to use for
outgoing connections.

I've seen boxes supporting more than a million connections with tuning
in the course of normal operation.

On 10/14/10 9:03 AM, johndole () hush ai wrote:
Hi,

I am somewhat new to networking. I have interest in running a 
Bittorrent tracker. I ran one for a bit, and my one Linux box 
running Opentracker gets overloaded. My connection is good, and 
most of it isn't being used. Just a lot of people connect, and use 
up all the 65k "free connections". I tried messing with the 
sysctls, but it didn't help too much (and just degraded the 
connection quality for everyone). It is not a malicious attack 
either as there is only a few connections per IP and they are 
sending proper Bittorrent tracker requests...

So what can I do? How can I have have open more than 65k concurrent 
connections on standard GNU/Linux?

Thanks for any ideas and suggestions.

-John





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