Every time I upgrade initscripts (at least, I assume it's initscripts that's doing it, since ifcfg-lo is owned by initscripts), the setting "IPV6INIT=no" in ifcfg-lo disappears and I have to put it back by hand.
Is there a reason you want it specifically there rather than in /etc/sysconfig/network?
No specific reason. I just want it somewhere that works. Isn't it conceivable that someone would want to enable IPv6 on some interfaces but not others?
Yes, but I'm not seeing the point for loopback - even for those with security concerns, there's no addtional exposure there.
VMware server doesn't work if IPv6 is active on any interface.
If I can disable IPv6 for all interfaces by putting it in /etc/sysconfig/network, great, I'm happy to do that, but surely the infrastructure should support disabling it on a per-interface basis, in which case why should loopback be treated any differently?
The best way to disable IPv6 entirely is to add 'install ipv6 /bin/true' to a modprobe.d file.
That being said, fixed in