Use a text editor and modify /etc/auto.misc, comment out any uncommented
lines, and add two new lines:
File: /etc/auto.misc
- cd              -fstype=iso9660,ro,nosuid,nodev :/dev/cdrom
+ #cd             -fstype=iso9660,ro,nosuid,nodev :/dev/cdrom
+ tmp -rw,soft,intr server1.example.com:/export/tmp
+ netinstall -ro,soft,intr server1.example.com:/export/netinstall