Previous versions of fli4l only supported booting from a floppy disk which is not possible anymore due to causes already described. There are many alternative possible nowadays, amongst them using an USB stick.
Many other boot media (CD, HD, network, Compact-Flash, DoC, ...) exist and fli4l may also be installed permanently on some of them (obviously only the read-write ones). fli4l may be booted in three different ways:
Before you try the more advanced installation procedures you should make yourself comfortable with fli4l by setting up a minimal version. If you want to use your fli4l as an answering machine or a HTTP-proxy later on, you already feel confident and have the experience of setting up a basic running system.
That said, four variants of installations are possible:
USB-Sticks are addressed as harddisks by Linux hence the same explanations as for the harddisk installation are valid here. Please note that the according drivers for the USB port have to be loaded via OPT_USB in order to access the stick with OPT_HDINSTALL.
All necessary files are on the boot medium and are extracted to a dynamically sized RAM disk while booting. Using a minimalistic configuration, it is possible to run the router with only 64 MiB of RAM. The maximum setup is only limited by the capacity of the boot medium and available RAM.
This corresponds to the CD version, with the only difference of the files residing on a hard disk instead, the term ``hard disk'' also enclosing Compact Flash from 8 MiB upwards and other devices which are accessed like hard disks under Linux. As of fli4l 2.1.4, you can also use DiskOnChip Flash memory from M-Sys or SCSI hard disks.
The limit for the archive opt.img is removed by disk capacity, but all these files have to be installed into a RAM disk of suitable size during the boot process. This increases the necessary amount of RAM if you use many software packages.
In order to update software packages (i.e. the archive opt.img and the configuration rc.cfg over the network), the FAT partition has to provide enough space for the kernel, the RootFS and TWICE the size of the opt.img archive! If you also want to enable the recovery option, the required space is increased one more time by the size of the opt.img archive.
In contrast to type A, most of the files are not put into the RAM disk. Instead, they are copied from the opt.img archive to the ext3 partition on the hard disk at the very first start after the initial installation or an update. On successive reboots they are loaded from the ext3 partition. Using this type of installation, the amount of RAM needed for running the router is the smallest, such that running the router with very low memory is possible in the majority of cases.
You can find further information on the hard disk installation in the documentation of the HD package (a separate download) starting at the description of the configuration variable OPT_HDINSTALL.