Unbound not starting when called as a service

Hi all,

I just installed unbound into an (iocage) jail, and put in place my usual config, adopted from the calomel.org example.

If I run it from the command line unbound, the server comes up, and all is normal.
However, if I try to start it as a service service unbound start:

# service unbound start
Obtaining a trust anchor:.
Starting unbound.
[1470480625] unbound[72900:0] warning: IPv6 protocol not available

This is the only feedback I get. I've enabled logging at debug level, and nothing gets logged.

I haven't edited the rc.d script, and at this point, I don't know where to start looking, other than there's probably something going on with the trust anchor.