How to enable IPv6 on subinterface in Linux using sysctl?

Question

I tried the following: sysctl -w net.ipv6.conf.Ethernet1.200.disable_ipv6=0, but it gave following error:

sysctl: cannot stat /proc/sys/net/ipv6/conf/Ethernet1/200/disable_ipv6: No such file or directory

It should have ideally tried to change in /proc/sys/net/ipv6/conf/Ethernet1.200/disable_ipv6

which it is not

I have used echo 0 > /proc/sys/net/ipv6/conf/Ethernet1.200/disable_ipv6, but I need some Linux command that does the same.

Answer 1

Because sysctl.conf uses dots as filesystem path separators, you have to use / in place of actual dots. Yes, it's weird like that.

net.ipv6.conf.Ethernet1/200.disable_ipv6 = 0

But you can actually use / as the separator, too:

net/ipv6/conf/Ethernet1.200/disable_ipv6 = 0

I would honestly suggest not disabling IPv6 by default; then the problem would be avoided.