"dnssec-lookaside auto;" This is the equivalent
of "dnssec-lookaside . trust-anchor dlv.isc.org;"
plus setting a trusted-key for dlv.isc.org.
Note: The trusted key is hard-coded into named,
but is also stored in (and can be overridden
by) $sysconfdir/bind.keys. As the ISC DLV key
rolls over it can be kept up to date by replacing
the bind.keys file with a key downloaded from
https://www.isc.org/solutions/dlv. [RT #18685]
