[Solved] IPv6 not disabling on eth0 during Pi2 boot

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1

I have used the following commands in sysctl.conf to disable IPv6:

   net.ipv6.conf.all.disable_ipv6 = 1
   net.ipv6.conf.default.disable_ipv6 = 1
   net.ipv6.conf.lo.disable_ipv6 = 1
   net.ipv6.conf.eth0.disable_ipv6 = 1

Running sysctl -p correctly activates these changes on both local and eth0.

However, if I reboot the system, eth0 is assigned an inet6 address according to ifconfig.

eth0 also gets an inet6 address if I disconnect and then re-connect the network cable after running sysctl -p.

I assume there’s some switch that’s overriding my settings when eth0 comes up. Any help pointing me in the right direction would be gratefully received.

2

I’m not surprised that doesn’t work, because we use connman as our network manager, so it will just override those manual settings.

To disable ipv6 on Ethernet you would use connmanctl:

osmc@rpi2:~$ connmanctl
connmanctl> services
*Ac Wired                ethernet_b827ebd04564_cable
connmanctl> config ethernet_b827ebd04564_cable --ipv6 off
connmanctl> quit

This change is persistent. Configuring the network interfaces from the command line is all done via connmanctl - type help while you’re in there and you’ll see there is a lot that can be done.

Tip - rather than typing out the full ethernet string just type e and hit tab…

1 Like
3

Thanks for the help. That works a treat!

5

Just a note - we now disable IPv6 by default, but you can use the above steps but with auto instead of off if you wish to turn IPv6 back on for a given interface.