FreeBSD LiveCD
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[uredi] Uvod
FreeBSD LiveCD Tool Set ima za cilj, da omogući svima da naprave svoje FreeBSD Live CD-e. FreeBSD LiveCD was born as a Brazilian FreeBSD korisnička grupa internal project and technical need. The main subject was to create a tool that would allow us a safe diagnostic method, under emergency enviroments and specially as a rescue disk where FreeBSD partitions could only be accessed (mounted) externally.
Despiste The FreeBSD Project officially distribute a "Live" disk, under most circunstances we needed some more functional tool, that could be run directly from an optic drive (CD) without any other intermediate resource. With this goal in mind, the LiveCD Project was started.
Its begin was in the October 5th of 2001, at the time where FUGSPBR (FreeBSD User Group, SP, Brazil) distributed an ISO image with a fully functional FreeBSD 4.4-STABLE LiveCD, that would allow one to access a number of partition types (since FreeBSD native to Linux and even DOS partitions), build a fully operant Firewall, allow networking flow via NAT, working as router and a number of other issues. We experienced a lot of feedback from some users that were trying this pretty first version, and soon many of those users were asking for custom versions of the LiveCD, with mail clients, some extra kernel support (like Bridging and Bandwidth control) and stuff. We had even made a LiveCD ISO that could run as a Desktop Enviroment - with lots of graphical applications. This version was a first one that could even be used as a FreeBSD Demonstration Disk. It had great adoption on our community, but the desire for even more custom versions was far from the end.
At this point, under those scenario, we decided to publically distribute the set of scripts that we were using to create the LiveCD, allowing anyone to create their own custom distribution. Thats when the FreeBSD LiveCD Tool Set was born. Since it's release, in January 2002 we are working hard to improve its functionality, we have set a lot of goals and are getting to everyone quickly. LiveCD Tool Set 1.2 is the latest version.
Since it was just an idea, and after the first CD, FreeBSD LiveCD has been used under many situations, where the most usual are Rescue Disk, Desktop, FreeBSD System demonstration at some computing specific shows, Firewalls, Wireless Bridges, Wired Gateways and, the main issue is that, as you can make a fully custom version, you can use a LiveCD under any enviroment you wish.
Not a few people use to ask us, exactly that is and how the LiveCD works. Its such a simple answer, its nothing but a set of Patches that are applied on the FreeBSD Initialization files, that allow the system to run from a cd-rom, setting the best way to mount under Memory File System (MFS) or Virtual Nodes (vnodes) the slices filesystems that need Write and Read access, while the Slices that just need Read access are still running on the CD. With a recent issue on version 1.2, it can now be used as a Instalation Disk, that allow you to install the system on your Hard Disk without any other Disk. It now supports batch-mode install, that allows one to easily automate any custom install process.
When booting a PC with FreeBSD LiveCD, you will be facing a true UNIX Operating System, full and completly functional, where you can run any application you need. If the CD Space are not anought to run your many programs, LiveCD allows you to use your FAT or EXT2 Disk Slices to install other programs - and even to save your permanent configuration - and if its your choice enviroment, you will be able to use it as instalation media.
The Documentation Process is running in both Portuguese and English languages, up to the time they will be released, if you have any question, doubt, feedback, wish or stuff, please subscribe to our mailing list. We will be pleasured to help you }:-)
[uredi] System Requirements
There are system requeriments when you are about to create your own custom LiveCD with the FreeBSD LiveCD Tool Set. At this point, you need a box running FreeBSD, and its source (/usr/src/) has to be syncronized with the FreeBSD -STABLE Branch (via cvsup, usually) and you need about 2GB free space under the /usr/local/ slice - this issue can be configured and the path changed - and mkisofs(8). The Tool Set has even a CD Creation routine, so a CD Recorder is always the main requirement when you wish to test your custom LiveCD, despiste it doesn't need to be present at the same machine you are creating the image.
At running time, it's a good idea to have about 64MB Memory, obviously because usually you will mount every Read/Write partition under MFS (memory filesystem) and read-only data will be brought to main memory everytime you need to read it - this issue is even more relevant if you run graphical applications.
[uredi] LiveCD Technical Overview
How to use it?
This Tool Set usage is an easy challenge. It is made up of only 3 shell scripts:
- LiveCD/livecd.sh - LiveCD/scripts/make_vnodes.sh - LiveCD/scripts/install_freebsd.sh
livecd.sh is the main shell script, it executes all the routines that are pertnent to the CD generation works. The user input interface is dialogged, so it's pretty easy to understand all the CD creation steps. The other 2 scripts are only support routines that may be used later, when you are already running LiveCD. They are issues.
livecd.sh usage.
Before running livecd.sh you must set some variable options at the config file. Those options will define the directory structure where the LiveCD generation will be made, the directory where the ISO image will be created, etc...
When you run livecd.sh a dialog box will show you every value defined at the config file. If you agree with those values, just press ENTER. If you want to redefine the values, abort the livecd.sh - just press Ctrl-C.
There are 8 steps need to create a FreeBSD LiveCD. Every step is shown - in order - at the livecd.sh main menu. You just need to run them at the sequence they are shown, and you will have a Live CD at the end of the process.
Steps "F" (burn CD) and "C" (insalling applications) are not required, it's up to you, to optionally use them.
At any time you can abort a step and restart the Cd Creation Process from the last step that was sucessfully ran. You don't need to restart the process from the begin when you abort something.
make_vnodes.sh usage.
This script can be found under /scripts on your LiveCD directory structure. It is used to easily handdle the set of files that can expand your filesystem facilities on LiveCD. When LiveCD boots, it will attempt to detect and mount FAT/NTFS/EXT2FS/UFS partitions, if they exist on your Hard Disk. Once LiveCD has identified and mounted a partition, you will be able to create virtual nodes at any of those FS, to install LiveCD programs, save permanent configuration data, and everything else you can do with larger writable nodes.
With virtual nodes you can have a 100% functional Unix Desktop, without needs to repartitioning your HD to install the system. This enviroment is not as safe as a native FreeBSD install, but it is a great way to try FreeBSD before definitively installing it. It's a great demonstration enviroment.
When you run the script, it will ask you where is the mount point for the .flp image files, and there, they will be created (ie. /mnt/dos.1). You only need to set the desired path.
After that, it will show you a menu, where you can choose wich .flp image nodes you wish to create. Selecting it, a dialog box will ask you the size (In MB) for that virtual node.
At the end of this process, you will have a .flp file created under the freebsd/ directory at the mount point you have chose. At the next boot time, LiveCD will find this file and will use it as a virtual node for the filesystem you have selected, and will use this vnode, not mounting this FS as Memory File System as usual :-)
install_freebsd.sh usage.
This script can be found under scripts/ directory at your LiveCD directory structure. It allows you to permanently install FreeBSD on your Hard Disk. The following requirements are needed to use this:
- If your Hard Disk is IDE Type, it must be controlled by your first IDE Controller - IDE-0, First IDE Master. - You can't have any other O.S. on your Hard Disk. You you wish to dual boot your system, we recomend you to try the usual installation media, distributed as Disk #1 by the FreeBSD Project. Our script will allocate the whole HD for the FreeBSD System. Any other partition or system will be overwritten. Here, our goal is to offer an advanced FreeBSD System installation media, and under production enviroment, FreeBSD should live alone in your box.
When you run it, this script will ask you to confirm the disk that it will install FreeBSD. Even if there are more than one Disk, it will show you always the first one. When you choose the disk, the script will ask you, via dialog boxes, 3 questions, asking the size you respectively want to allocate for the /, swap and /var partitions. /usr size definition will be auto allocated, based on the remaining Hard Disk free space. After that, a confirmation window will prompt, and if you continue the process, it will delete all data on your disk, will define de proper disk information and will install FreeBSD.
After a few minutes, the installation process will be done. Remove your LiveCD cd-rom and reboot your system.
You may also run this scrint on a non-interactive way, allowing you to run it in batch-mode. In example, if you issue the commands:
/scripts/install_freebsd.sh ad0 300 256 1000
It will install FreeBSD at ad0 disk, creating a 300Mb partition for the / FS, 256Mb for swap, 1Gb for /var the the remaining disk space for /usr. When you run it this way, NO EXTRA DATA WILL BE REQUIRED, so TAKE CARE, the process will start automatically and will only stop after the whole installation os done.
- Using LiveCD as a Rescue Disk (Disaster Recovery)
The ability to install FreeBSD from LiveCD was a requirement at the FUGSPBR. We wanted a Tool that would make simple a task of reinstalling a previously configured server if hardware problem happened.
You can create a very custom version of the whole script-set, allowing it to create your own partition definitions, and the ability to install previously configured programs (like Apache, Postfix, Samba, etc...) together, the easy batch-mode install may become a great tool that allows you to recover server enviroments.
A good idea is to create a rc.local file under your LiveCD's /etc/ ant set the desired parameters to call install_freebsd.sh. This way, when you boot a machine with LiveCD, automatically the install process will begin :-)
So, if you create your own LiveCD and keep it up to date - a scenario where a CD-RW would perfectly fit your needs - you will make the new server installation task as trivial as a single system boot. Obviously you may also try those features to "clone" your servers.
Conclusions.
LiveCD usage possibility are numerous. You may customize your scripts, create very own CD sets up to your imagination limits. Anyway, as soon as you start using LiveCD, as rescue disk, install disk, demonstration stuff, etc, it is a fact that you will wish to keep your own LiveCD up to date. This way, we desire you luck and a smart usage of this tool set.
Extra Information.
Memory is always an issue when you run LiveCD. The quality and compatibility of your memory cards - when you have more than one - must be certain. If reliable memory is not reality, you may find 'strange' behavior on some programs (like coredumps, signal 10 and 11), because the Memory File System is a wide used feature.
Firts Boot.
If you did not customize user/group and passwords, the default root account is passwordles. Enjoy ;-)
