Linux下关闭ipv6

Since I experienced slow DNS lookup with Debian testing/unstable, I felt I need to disable IPv6   this has largely been blamed for that, and it’s not really needed by most of the people.

When MDLog:/sysadmin posted Disable IPV6 module on default kernels, this remembered me there is more than one way to do it  and it was painful to some people.

Here’s the summary of what I can think of, with alternate methods in case the first one doesn’t work with you:

   Debian kernel 2.4:

       In /etc/modutils, change the line

       alias net-pf-10 ipv6

       to

       alias net-pf-10 off

       alias ipv6 off

       Reboot.

   Debian kernel 2.6/Ubuntu (“official” method)/Fedora Core

(method 1):

       In /etc/modprobe.d/aliases, change the line

       alias net-pf-10 ipv6

       to

       alias net-pf-10 off

       alias ipv6 off

       Reboot.

   Debian kernel 2.6/Ubuntu (alternate method):

       In /etc/modprobe.d/blacklist, add a line

       blacklist ipv6

       Reboot.

RHEL/CentOS:

    In /etc/modprobe.conf, make sure you have

    alias net-pf-10 off

    alias ipv6 off

    Reboot.

RHEL/CentOS/Fedora Core (method 2)/Mandriva (method 1):

    In /etc/sysconfig/network, add a line

    NETWORKING_IPV6=”no”

    Reboot.

SuSE 9.0:

    In /etc/modules.conf, change the line

    alias net-pf-10 ipv6

    to

    alias net-pf-10 off

    alias ipv6 off

    Reboot.

SuSE 9.1/9.2/9.3/10.0 (“official” method):

    In /etc/modprobe.conf, change the line

    alias net-pf-10 ipv6

    to

    alias net-pf-10 ipv6

    install ipv6 /bin/true

    Reboot.

   SuSE 9.1/9.2/9.3/10.0 (alternate method)/Mandriva (method 2)/Slackware:

       In /etc/modprobe.conf, make sure you change

       alias net-pf-10 ipv6

       to

       alias net-pf-10 off

       alias ipv6 off

       Reboot.

   Gentoo:

       In /etc/modules.d/aliases, make sure you change

       alias net-pf-10 ipv6

       to

       alias net-pf-10 off

       alias ipv6 off

       Reboot.

NOTES:

       In distros using /etc/modprobe.conf, beware that you might get  overriden by /etc/modprobe.conf.local or by /etc/modprobe.d/*.

If you disable IPv6, I suppose you don’t need tunnels either. You could also

add there:

       install sit0 /bin/true

       A last “anti-IPv6″ issue: don’t forget the old trick of checking if your Firefox

       has IPv6 disabled:

           o  CTRL+L, about:config (Enter)

           o  Filter by ipv6.

           o  Set network.dns.disableIPv6 to true.