Disable IPV6 within LXC Container

Hi folks, I tried to disable IPV6 within a LXC Container.
But I have no success.
When I do this
echo 1 > /proc/sys/net/ipv6/conf/all/disable_ipv6
I have bash /proc/sys/net/ipv6/conf/all/diable_ipv6 / read-only file system.

I tried also to disable it from the Host its OK on the host but not within the container.

I am with LXC 1.0.11 on CentOS 7.5.

Many Thanks for your reply.