To come to the point: I am currently not able to make my ESXi host use IPv6!
The main reason for this is that my hosting provider uses a link-local address (fe80::1 in my case) for the IPv6 gateway. This is not a problem with any other Operating System that I stumbled over so far, but ESXi 5.1 refuses this:
|Broken link-local support in VMware ESXi 5|
Unfortunately the work around that Cisco recommends - using router advertisements to auto-configure the IPv6 address and gateway - does not work for me either, because my hosting provider does not provide router advertisements, but requires statically defined addresses and routers.
So I am stuck for now ... but that's not all: When taking a closer look at the IPv6 implementation in ESXi I found even more limitations that you won't find in other Operating Systems:
- The default gateway address must be on the same subnet as the interface's address
- You cannot define static routes for a specific interface (if you have multiple vmknics that are IPv6 enabled)
- When adding a static route you must provide an address for a gateway. Other OSs will allow you to bind a route to just a specific interface and omit the gateway. This is useful for cases where another IPv6 address is directly reachable although it is on a different subnet.