Pro-tip: BSD default sysctl net.link.ether.inet.maxhold of 1 is incompatible with Happy Eyeballs concurrent DNS resolution when resolver is not in arp/ndp cache. DNS queries get lost.
Go's non-cgo resolver triggers this and leads to 5s stalls in DNS resolution on BSD when resolver not currently in kernel neighbor cache.
Linux's equivalent documented in man-pages as value 3, in kernel docs & reality is 101.
net.link.ether.inet.maxhold=10 going into my /etc/sysctl.conf files now.