[Solved] [BOOKWORM] How to completely disable IPv6?

[Danielsan]

Hello there,

is there a way to completely disable IPv6?

So far the only working method I found is adding ipv6.disable=1 to GRUB; however this workaround doesn't block it completely, it only prevents to be used. The point is I don't run an ISP, I don't need IPv6, I don't want to see IPv6 utterly complicated stuff when I use Debian. It should be asked during the installation (and after a dist-upgrade) if you want enable IPv6, otherwise Debian is becoming and acting like Canonical does with Ubuntu.

[kc1di]

you can disable it in network manager by going to configure network connections click on your link and got to Ipv6 and there is a drop down box at the bottom of that list is disable. do it for both ethernet and wifi if you have them.

[peter_irich]

You can also place record

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net.ipv6.conf.default.disable_ipv6=1

in /etc/sysctl.confand enter command as root

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sysctl -p

See /proc/sys/net.

[Aki]

Hello,

[..] adding ipv6.disable=1 to GRUB [..] however this workaround doesn't block it completely, it only prevents to be used. [..]

So what do you want to achieve that disabling IPv6 from grub will not allow ?

The ipv6 kernel module is compiled as a built-in part of the Debian kernel and this cannot be modified at install time (even if the debian developers wanted to):

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# grep CONFIG_IPV6= /boot/config-$(uname -r) 
CONFIG_IPV6=y

If you wish, you can rebuild your own custom kernel disabling the compilation of IPV6 module. Are you willing to do this for the sake of block it completely ?

[Danielsan]

You can also place record

Code: Select all

net.ipv6.conf.default.disable_ipv6=1

in /etc/sysctl.confand enter command as root

Code: Select all

sysctl -p

See /proc/sys/net.

This method did not work.

So what do you want to achieve that disabling IPv6 from grub will not allow ?

The ipv6 kernel module is compiled as a built-in part of the Debian kernel and this cannot be modified at install time (even if the debian developers wanted to):

Ah this make sense. The point is when you disable it by grub it says that is active but disabled. My personal point since I don't use and I need it too. But I didn't know that it was hard coded in the kernel.

[Aki]

Hello,

[..] The point is when you disable it by grub it says that is active but disabled.

This is the message in the kernel ring buffer (dmesg) when the ipv6.disable=1 kernel option is active:

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[    6.295172] IPv6: Loaded, but administratively disabled, reboot required to enable

My personal point since I don't use and I need it too. But I didn't know that it was hard coded in the kernel.

Well, as I wrote above, you can recompile the kernel to disable it completely. The message will no longer appear.

Please, mark the discussion as "solved" manually adding the text tag "[Solved]" at the beginning of the subject of the first message (after other tags, if any); for example:

[BOOKWORM] [Solved] How to completely disable IPv6?