- NanoBSD is designed to put a possibly reduced FreeBSD system - on a Compact Flash card (or other mass storage of your choice) - in a way which is suitable for use in appliance like applications. -
- The mass storage is divided into three parts, two image partitions - and a configuration file partition, which normally are mounted - only read-only. This means that it is safe to pull the power - plug on a NanoBSD machine and that Flash based storage is not worn - out with filesystem metadata writes. -
- Having two image partitions means that it is possible to download - a new image while the system is running, reboot to run that new - image and if that fails somehow, it is still possible to switch - back to the old image partition. - -
- The Nanobsd build system lives in src/tools/tools/nanobsd - and consists of makefiles and shell scripts which drives use of - the Makefiles in the FreeBSD source tree to create a NanoBSD image. -
- The necessary commands to build a NanoBSD image are: -
- Depending on your machine, this will take from half an hour - to some hours. The process is split into a sequence of - steps, and if errors happen underway it is generally, but - not always possible to rectify the error and type make - again to complete the missing steps. -
- If you want to start from scratch you have to delete all files - and directories in the NanoBSD directory which start with an - underscore: rm -rf _.* -
- Here is a breakdown of the files and directories which NanoBSD - builds, in the order they are built: -
The output from running make buildworld in the - source tree. -
If this step fails, the output is instead left - in the file _.bw.tmp -
The output from running make installworld DESTDIR=_.w - in the source tree. -
If this step fails, the output is instead left - in the file _.iw.tmp -
This is the directory tree into which installworld installs. -
The output from running make distribute DESTDIR=_.w - in the source trees etc subdirectory. -
If this step fails, the output is instead left - in the file _.di.tmp -
The output from running make buildkernel - in the source tree. -
If this step fails, the output is instead left - in the file _.bk.tmp -
The output from running make installkernel DESTDIR=_.w - in the source tree. -
If this step fails, the output is instead left - in the file _.ik.tmp -
The output from running the customization scripts in the - Customize subdirectory. -
If this step fails, the output is instead left - in the file _.cs.tmp -
The output from building the image file containing the filesystem - images of the finished NanoBSD. -
If this step fails, the output is instead left - in the file _.md.tmp -
Mtree(8) output from the files installed into the code patitions - in the NanoBSD image. -
Image file containing the full disk image. This is the image - file you will put on the Compact Flash or other mass storage from - which your target platform boots. -
Image file containing just the code partition image. This is - image you will download to update a running system. -
- This is where things get interesting, and where you will be spending - your time when developing with NanoBSD. -
- The first thing you need to configure is how much storage - you have on your mass storage media. NanoBSD can work out - of the box with as little as 64MB, and if you spend time on - it, you can cut it down even further until you end up with - an installed system with just the kernel and two or three - files in userland. -
- You can determine the size of the storage media with the - diskinfo(8) command or by examining dmesg(8) or console - output during boot. -
- Once you know the number of sectors on the entire media - insert this in the Makefile in the definitions of - SECTS or pass it as a command line option to make(1) when - you build NanoBSD: MAKE SECTS=100000. -
- Some platforms need to use CHS addressing in the bootblocks - in which case you need to set the HD and SC - values in the Makefile as well. These can also be found from - diskinfo(8), dmesg(8) or console output. Even if your current - platform does not need these to be set, it is always a good idea - to do it anyway. -
- Please be aware that you have to get the values used on the - target platform. Putting a CF card in a USB-CF adapter will - not result in the correct values for the geometry. -
- The DATASIZE parameter controls how many sectors are - used for the configuration partition. Typically you will need - very little, but depending on your application and how you - organize things, you may want to set this higher or lower. - Obviously, the space you use for the configuration partition - is not available for the image partitions. -
- You can run scripts which will customize the NanoBSD image - by listing them in the CUSTOMIZE variable in the - Makefile. The scripts will be given arguments to show them - where everything is and they can do pretty much anything - they want to do to the directory tree. -
- The make.conf file overrides the usual /etc/make.conf - and by default disables a lot of FreeBSD from the build in order to - make it fit on 64MB devices. Go through the list and decide if there - are anything you want or do not want in your NanoBSD image. -
- You may also want to use a kernel other than GENERIC. - Put the config file in ../../../sys/i386/conf and - set the name in KERNCONF in make.conf. -
- You can save a couple of megabytes of space in your image by - removing all the bits you will not need. (How many appliances - need support for nine different RAID controllers ?) -
- By default the following customize scripts are provided (but not - called unless you list them in CUSTOMIZE. -
- Disables getty(8) on the VGA devices and enables console in the - COM1 serial port. -
- Disables the "beastie-menu" in the bootloader. -
- Disables ata-dma for the Soekris NET4801 because early hardware - versions do not support DMA on the CF socket. - - - &footer; - -