Bug 22718

When running /stand/sysinstall as released, records are generated
in /etc/rc.conf that are not processed correctly during startup.
An example rc.conf follows (as generated by /stand/sysinstall).
Note lines which have *=YES="NO" etc...  also note that ip addresses
and machine names have been obscured by me.

# This file now contains just the overrides from /etc/defaults/rc.conf
# please make all changes to this file.

# -- sysinstall generated deltas -- #
lpd_enable="YES"
nis_client_enable="YES"
nfs_client_enable="YES"
ifconfig_fxp0="inet xxx.xxx.xxx.xxx  netmask 255.255.255.0"
hostname="somehost.somedomain.com"
linux_enable="YES"
moused_enable="YES"
saver="daemon"
defaultrouter="xxx.xxx.xxx.xxx"
nisdomainname="nisdomain.com"
ntpdate_enable="YES"
ntpdate_flags="ntpmachine"
xntpd_enable="YES"
# -- sysinstall generated deltas -- #
nis_client_enable=YES="NO"
# -- sysinstall generated deltas -- #
nis_client_enable=YES="YES"
# -- sysinstall generated deltas -- #
lpd_enable=YES="NO"
ntpdate_flags="none"
ntpdate_enable="NO"

Fix: 

Temp work around is to edit the /etc/rc.conf file, I didn't look at
the code for sysinstall.
How-To-Repeat: Run /stand/sysinstall and go to network configuration.  Turn on
or off NFS client (for instance) and look at /etc/rc.conf.