[CentOS] Re: rolling your own kernel - guidelines?

Thu Oct 4 22:13:35 UTC 2007
Florin Andrei <florin at andrei.myip.org>

Scott Silva wrote:
> I would recommend not using the latest and greatest kernel with an 
> Enterprise distro. You have a good chance of breaking it. If you want 
> new, use Fedora Core. If you want stable, use CentOS and don't poke the 
> bear!

Honestly, all I need CentOS for is a reliable source of convenient 
package updates for the systems. Plus the fact that being a Red Hat 
clone makes it easier to find people with appropriate skills.

These systems will be minimal installs - even less than the default 
minimal that can be achieved via Anaconda, plus a couple custom 
packages. Think - home-made appliances, or sorts. There will be very, 
very few things running on these machines.

The problem with kernel 2.6.18 is that netfilter has the old (I mean, 
current) braindead conntrack that is loaded when NAT is used.
Now, configure pktgen full blast over a gigabit link, small UDP packets, 
set it to generate random source IPs (DDoS simulation) and point it to a 
Linux router with conntrack loaded, and you'll see why I can't use the 
default kernel.

Apparently there will be improvements in that regard in 2.6.23, and I've 
heard that 2.6.24 will actually be able to do 1:1 NAT without conntrack.

-- 
Florin Andrei

http://florin.myip.org/