How many IP can we bind on a single eth0 interface

husainar · 05-16-2009, 08:41 AM

Hi there,

How many IP's can we bind on single eth0 interface ?

jschiwal · 05-16-2009, 09:52 AM

I don't know if the kernel imposes a limit. It may make more sense to use the firewall to translate the IP addresses for a very large list of IPs.

husainar · 05-16-2009, 10:08 AM

In case you mean NATing then that does not really do any good.. can you please explain me what you really mean by it..

Thanks,

estabroo · 05-16-2009, 12:35 PM

somewhat less then 4228250625

jschiwal · 05-18-2009, 03:04 AM

Maybe you could explain why you need a lot of IP addresses.

husainar · 05-18-2009, 05:49 AM

Planning to setup a shared server which will have multiple subdomains and each subdomain will have a dedicated IP for their SSL.

Thanks,

barunparichha · 05-18-2009, 06:00 AM

Can anyone explain how you are calculating this figure ?

I guess IP class also comes into picture.

estabroo · 05-19-2009, 07:22 AM

well my number was 255^4 (though that is still wrong). I'd say your practical limit is less than 1024, probably much less if the domains will be very active, simply because the box will have too much work to do. Truthfully though you can set up the network device as promiscious and answer for every ip in the ipv4 space (this is how quite a few tar pits work), though it would require some code changes to actually run your web services that way.

barunparichha · 05-19-2009, 08:47 AM

we cant take all the 32 bits for calculating the IP for IpV4.

GaganBrahmi · 05-19-2009, 10:00 AM

Quote:

Originally Posted by estabroo

well my number was 255^4 (though that is still wrong). I'd say your practical limit is less than 1024, probably much less if the domains will be very active, simply because the box will have too much work to do. Truthfully though you can set up the network device as promiscious and answer for every ip in the ipv4 space (this is how quite a few tar pits work), though it would require some code changes to actually run your web services that way.

In such case there won't be any load on the server as there will not be any CPU activity. It will just be the network packets which will be coming in picture.

This is a really good question and even I have tried to look around to get answer to this. I certainly hope that someone over here may have the answer to this.