Sync mDNS with upstream
The mDNS code in illumos is lagging upstream, and one issue as a result of this is that when running illumos on a network with a newer OSX machine, an unsupported mDNS message option is logged to syslog and the console:
mDNSResponder: [ID 702911 daemon.error] ERROR: getOptRdata - unknown opt 4
every few seconds.
In SmartOS we have simply removed the logging however it would be useful at some point to investigate further as to whether we should integrate the latest mDNS code from Apple which has support for this option (as well as kDNSOpt_NSID which illumos is also missing).