1) Download ipcop-1.4.18-install-usb-hdd.i386.img.gz

2) Backup your USB key if there is a file inside it … we gonna format the USB key after u already backup

3) You can format USB pen drive with the help of following commands:

[a] fdisk : Partition table manipulator for Linux

[b] mkfs.ext3 : Create an ext2/ext3 filesystem by formatting given partition name (/dev/partition)

[c] e2label : Change the label on an ext2/ext3 filesystem

First make sure USB pen is not mounted. Click on Places > Computer > Select USB pen > Right click > Select Unmount Volume.

Let us assume that /dev/sda1 is your partition name for USB pen. To format type the following command (Open X terminal and type the command)

$ sudo mkfs.ext3 /dev/sda1

Caution: Careful while entering device/partition name; wrong name can wipe out entire hard disk!!!
Now use e2label command to change the filesystem label on the ext3 filesystem located on device /dev/sda1:

$ sudo e2label /dev/sda1 usb-pen

You can also create an MS-DOS/Windows XP file system under Linux, enter:

$ sudo mkfs.vfat /dev/sda1

Now you are ready to use USB pen for IPcop.

4) Next step, using linux :

zcat  ipcop-1.4.18-install-usb-hdd.i386.img.gz > /dev/sda (type it without partition number)

U r Done !!!!!

*p/s : plz check your usb drive partition detected from dmesg & make sure ya machine support boot from USB.



ref :  http://blog.myfenris.net/?p=366