It seems that there has been a regression between 8.1-RELEASE and 10.1-RELEASE in mountd. In 10.1 I can no longer run mountd with -h myhostname to have it bind to the IP that "myhostname" resolve to. The cause is that getaddrinfo() is not being called correctly. I've uploaded a fix for review here: https://reviews.freebsd.org/D1507