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Where is right place for sysctl redefined values?

I have:

> uname -a
Linux note 3.1.0-1-amd64 #1 SMP Tue Jan 10 05:01:58 UTC 2012 x86_64 GNU/Linux

> cat /etc/debian_version 

> tail -n 2 /etc/sysctl.conf   

But after each reboot net.ipv6.bindv6only still 1

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up vote 5 down vote accepted

Check if there is a file in /etc/sysctl.d with your parameter. These files override the /etc/sysctl.conf file...

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yep. i found /etc/sysctl.d/bindv6only.conf thanks – Korjavin Ivan Feb 1 '12 at 11:18

/etc/init.d/ comes too early in the boot process to apply a lot of sysctl's. As it runs before networking modules are loaded and filesystems are mounted, there are quite a lot of commonly-used sysctl's which are simply ignored on boot and produce errors to the console.

All documentation on the net referring to changing certain settings in /etc/sysctl.conf such as net.ipv4.netfilter.ip_conntrack_max is wrong for Ubuntu & Debian.

Finally, "It seems to me it is a Debian Squeeze bug, see here for an example and workaround:

In the latter case, the procps init script should take care of loading them during boot. However, on Squeeze it does not, and you need to restart it from /etc/rc.local (or similar):

# /etc/rc.local

# Load kernel variables from /etc/sysctl.d
/etc/init.d/procps restart

exit 0
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If you use ufw (uncomplicated firewall) you really need to change the values in /etc/ufw/sysctl.conf as the configuration here overrides /etc/sysctl.conf one.

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Thank you. But no, i did not use ufw. Problem was solved, data was redefined in /etc/sysctl.d – Korjavin Ivan Aug 17 '12 at 3:34

This is set by the procps init script. make sure this init script is enabled with update-rc.d procps enable. If it is enabled you should expect a link from a file in /etc/rcS.d to /etc/init.d/procps. If this init script is working correctly manually running /etc/init.d/procps restart should make the setting.

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You mean Debian doesn't read sysctl.conf by default? wow. – James O'Gorman Jan 31 '12 at 18:59
it reads sysctl by default. the /etc/init.d/procps mecahnism is the default mechanism. If my answer works, it is because this init script was disabled for some reason, which might be a bug. A bug causing this would not be surprising since he is running either the testing or unstable release of debian (or some combination thereof) – stew Jan 31 '12 at 19:06
> sysctl net.ipv6.bindv6only net.ipv6.bindv6only = 1 doesnt works – Korjavin Ivan Feb 1 '12 at 11:17

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