RHEL6 - disable IPv6 on an interface

I've been having fun upgrading, or should one say migrating to RHEL6 (Scientific Linux 6.1). As run KVM (Virtualization) I have a bridge running for my VM to connect to the network.

Now I suddenly noticed that IPv6 was enable on my 'eth0' which is part of the bridge, this should not happen as it can cause communication issues (yes I got IPv6 enabled devices on my network). So after a bit of searching I found a bug from Redhat (bug#496444) which states that IPV6INIT=no does not work for a single interface, in fact it does not work at all. The bug is still open.

Now after a bit of searching I found something which works just fine:

# echo 1 > /proc/sys/net/ipv6/conf/ethX/disable_ipv6

To make this permanent add it to /etc/rc.d/rc.local then IPv6 will get disabled every time the server restarts.

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