Hi,
On a system running FC3 I have 2 NIC cards. I would like to activate IPv6 only on one card and only IPv4 on the other one.
As soon as ipv6 kernel module is loaded, it will assign link local IPv6 addresses to all interfaces on the system. There's nothing you can do about it. Basically, that is what it is supposed to do. Since link local addresses are not routable, and there isn't much usefull you can do with them, you can simply ignore the fact that your eth0 has it assigned.
The settings you have in ifcfg-eth0 should prevent that interface from getting any other kind of IPv6 address (that might be routable).
If you are paranoid about it, simply configure ip6tables to block anything you might not want. Something like this in /etc/sysconfig/ip6tables should do the trick in your case (of only two NIC cards):
*filter :INPUT DROP [0:0] :FORWARD DROP [0:0] :OUTPUT DROP [0:0] -A INPUT -i eth1 -j ACCEPT -A OUTPUT -o eth1 -j ACCEPT COMMIT
You'll need ip6tables package installed, and ip6tables service enabled for this to work.
As Alexander suggested, you can also manually delete link local IPv6 address from the interface. However, since ipv6 module is loaded on-demand, you never know exactly when it is going to be loaded, so you don't know exactly when those addresses will be assigned to the interfaces.
-- Aleksandar Milivojevic <amilivojevic@xxxxxx> Pollard Banknote Limited Systems Administrator 1499 Buffalo Place Tel: (204) 474-2323 ext 276 Winnipeg, MB R3T 1L7
