Install pfsense to an usb drive

Nanobsd was created to make Freebsd suitable for installing on embedded systems, specifically on flash media.
Flash media has a limited number of write cycles and a standard install can burn through them quickly resulting in drive failure.

Nanobsd avoids this by logging to ram only and mounting the file system read only (among other tweaks).
Because of this some packages cannot work. Most have been adapted to work, for example it's possible to run squid without the cache just as a web filter.

SANDISK CRUZER FIT 4GB USB FLASH DRIVE

Download embedded builds image 4G with VGA output from:

http://files.nyi.pfsense.org/mirror/downloads/pfSense-2.0.2-RELEASE-4g-i386-nanobsd_vga.img.gz

Writing the image
When using a windows machine the easiest way to write your media is with physdiskwrite.
Place physdiskwrite and the pfSense image in the same folder. Attach the media you want to store pfSense on (i.e. CF-Reader and CF-Card).

Physdiskwrite will show you a numbered list of suitable devices (USB-stick, CF-cards in USB-readers, harddisks,...). Enter the number of the desired media.

physdiskwrite v0.5.2 by Manuel Kasper

Usage: physdiskwrite [-u] [-d driveno]

-u remove 2 GB restriction (WARNING!)
-d specify drive number (0..n) (no confirmation prompts!)

X:DownloadspfSense>physdiskwrite.exe -u pfSense-2.0.2-RELEASE-4g-i386-nanobsd_vga.img.gz

physdiskwrite v0.5.2 by Manuel Kasper

Searching for physical drives...

Information for .PhysicalDrive0:
Windows: cyl: 29185
tpc: 255
spt: 63
C/H/S: 16383/16/63
Model: INTEL SSDSC2CT240A4
Serial number: CVKI2455002X240DGN
Firmware rev.: 335t

Information for .PhysicalDrive1:
Windows: cyl: 91201
tpc: 255
spt: 63
C/H/S: 16383/16/63
Model: ST9750420AS
Serial number: 6WS17Q68
Firmware rev.: 0002DEM1

Information for .PhysicalDrive2:
Windows: cyl: 486
tpc: 255
spt: 63

Which disk do you want to write? (0..2) 2
WARNING: that disk is larger than 2 GB! Make sure you're not accidentally
overwriting your primary hard disk! Proceeding on your own risk...
About to overwrite the contents of disk 2 with new data. Proceed? (y/n) y
Found compressed image file
3989970432/3989970432 bytes written in total

Reference:
http://doc.pfsense.org/index.php/Installing_pfSense
http://forum.pfsense.org/index.php/topic,57064.0.html