Many people have heard of and have used RAM disk images under Linux, but did you know you can do the same thing with Solaris 10? Well, it's a little known fact, but you can, which is great for the potential of using Solaris 10 or OpenSolaris on embedded devices or even on security devices like firewalls.
Here is a quick method (courtesy of Peter Buckingham on one of our internal aliases) on creating a RAM disk image under Solaris 10 x86/x64 or OpenSolaris x86/x64:
/boot/solaris/bootenv.rcand remove "
/tmpso it's not swap backed
/boot/solaris/bin/root_archivecommand to build the RAM disk image:
# /boot/solaris/bin/root_archive pack solaris.img <dir>
... where <dir> is the directory you've got your working filesystem in.
Now you have a RAM disk image, there's nothing really stopping you from loading it from the network via pxegrub/pxelinux, or from a local disk.