Thus spake Caffeinate The World ("CTW> ") sometime Today...

CTW> > I'm testing freevrrpd on netbsd and I came across the fact that
CTW> > FreeBSD
CTW> > ALWAYS uses a netmask of /32 on it's alias IP no matter what the real
CTW> > netmask is. On NetBSD, I've always used the same netmask as the
CTW> > interface's real IP.

AFAICT, one must use a netmask appropriate to the network on which the
alias lives:

hme0: flags=8a63<UP,BROADCAST,NOTRAILERS,RUNNING,ALLMULTI,SIMPLEX,MULTICAST> mtu 1500
	address: 08:00:20:8e:65:05
	media: Ethernet autoselect (100baseTX full-duplex)
	status: active
# Internal (house) network.  /24.  That's all I need, and NATing anything
# else is just insane.
	inet 10.11.11.11 netmask 0xffffff00 broadcast 10.11.11.255
# External real-world address for www, ftp, etc.  /29 (8 addrs)
	inet alias 64.139.13.178 netmask 0xfffffff8 broadcast 64.139.13.183
# NAT address to the outside world (this is my NAT box), also /29
# since it's within the same address space as the above.
	inet alias 64.139.13.181 netmask 0xfffffff8 broadcast 64.139.13.183

				--*greywolf;
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