Re: [PATCH 33/33] Enable netfilter in netns

Patrick McHardy
2008-10-02T10:01:34Z

Alexey Dobriyan wrote:
> On Thu, Oct 02, 2008 at 11:12:08AM +0200, Patrick McHardy wrote:
>
>> Is there an easy way to test all this stuff?
>>
>
> I used the following:
>
> 0) netns is currently mutually exclusive with sysfs, so depending on
> sanity of distro initscripts booting sysfs-less kernel can be tricky.
>
> In Gentoo, for example a) rm -rf /sys (sic!), b) RC_USE_FSTAB="yes",
> c) RC_DEVICES="static" in /etc/conf.d/rc are needed.
>
> 1) netns creation tool (attached, some container guy posted it somewhere)
>
> # ns_exec -n /bin/sh
>
> 2) shutdown network in init_net
>
> sudo /etc/init.d/ntpd stop
> sudo /etc/init.d/sshd stop
> sudo /etc/init.d/iptables stop
> sudo /etc/init.d/ip6tables stop
> sudo /etc/init.d/net.eth1 stop
> sudo /etc/init.d/net.eth0 stop
>
> 3) move netdevices to netns
>
> ip l s dev eth0 netns "$1"
> ip l s dev eth1 netns "$1"
>
> where $1 is PID of shell from 1)
>
> 4) in netns start everything back
>
> sudo /etc/init.d/net.eth0 start
> sudo /etc/init.d/net.eth1 start
> sudo /etc/init.d/iptables start
> sudo /etc/init.d/ip6tables start
> sudo /etc/init.d/sshd start
> sudo /etc/init.d/ntpd start
>
> 5) at this point my usual NAT setup is back working for me and everything should
> be like in init_net (modulo aforementioned exceptions) and
> independent from init_net.
>
> Leaked netns are in /proc/slabinfo under "net_namespace".
>
> Some IPv6 printks can be annoying, so mute them.
>
> Object poisoning with SLUB won't work for irrelevant reasons, so use SLAB.
>
> Something like that.
>

Thanks, I'll give it a try.