#Not Yet another installer for OpenBSD

NYaifO use the autoinstall(8) feature of OpenBSD 5.5 to create an hand & console free installation of OpenBSD.

#YES no code (yet), but you do not need code or patch for this!

This README come from a blog post

#Wait, there is some now!

Start adding a makefile to make things simpler. Currently it only generate a normal OpenBSD ramdisk, no auto-install yet.

This makefile is clearly influence by the one of YaifO.

##Warning

It is the first time I mess with /usr/src, and play with compiling my own image of OpenBSD. So everything may{be| feel} hackish {and|or} dirty. Constructive criticism more than welcome.

I do not cover cross compilation here, and I only did test this with the amd64 distrib. But I do not see any reason that may prevent this to work on other distrib.

##What is this?

It is a guide (and maybe in a near future, a series of patches) to create a miniroot55.fs system, that will be dd(1)'ed on the hard drive, and will boot the server to automatically install OpenBSD 5.5 on it. Without the need to have access to a console on the machine.

The short term goal here is to have a quick & dirty way to install OpenBSD when you can not access the console output of the machine.

The long term may be to create a specifically tailored installer for this. See that has a really long term objective.

I would love to have feedback on this, since I am not really an OpenBSD hacker :)

##What do you need

• A working OpenBSD 5.5 system (VM is okay, I used a Virtualbox VM for this)
• The comp.tar.gz set installed
• The source tree in /usr/src/ (src.tar.gz & sys.tar.gz from your favorite ftp)

##Support

• Basic install of OpenBSD booting directly from your hard-drive

##Enhancement (non exhaustive list)

• A way to partition the disk using a definition file. Currently this use the default scheme, which may no fit your server need.
• I think my make commands are suboptimal, compiling more that needed.
• Translate this to French

##How to do it

We are going to modify the miniroot source and some file from your distrib (amd64 in my case), which lay in /usr/src/distrib/{miniroot|amd64}.

###Create an install.conf

Create the file /usr/src/distrib/miniroot/install.conf. See autoinstall(8) for more info.

Here is the one I will use for this demo:

System hostname = test_auto_install
Password for root = <the_root_password>
Do you expect to run the X Window System = no
What timezone are you in = Europe/Zurich
Use (W)hole disk, use the = W
Location of sets = http
Server = ftp.ch.openbsd.org

Avoid putting the root password in clear! You can use encrypt(1) to generate an encrypted version of your password:

# encrypt -b 8
dummypass
$2a$08$ZOm7pTQh4R8veZ7NbMn9Nuw14o4.eTTbabtGZWo5x8COwg5FblD3W
^C

If you look at the man page of autoinstall you will see that the install.conf file use a question = answer format. You are not forced to put the whole question, just a non-ambiguous part (and no question mark).

When configuring the disk, OpenBSD will use an existing OpenBSD area by default when one exist. Because the miniroot55.fs will be dd'ed on the target hard drive, an OpenBSD area will exist, but will only have a size of ~3.5MB. So we have to add the Use (W)hole disk, use the = W question in the answer file. Otherwise the system will not use the whole disk.

###Add it to the files tree

Now modify /usr/src/distrib/amd64/common/list, and add this lines somewhere:

# copy file in /
COPY    ${CURDIR}/../../miniroot/install.conf   install.conf

This will add our install.conf file in the root of the miniroot image.

###Modify the installation question

Since we do not boot with netboot, the installation will not start automatically after a timeout. So we are going to force the script to start in autoinstall mode.

The (I)nstall, (U)pgrade, (A)utoinstall or (S)hell? interactive question is in /usr/src/miniroot/dot.profile. Between the lines 92 and 123.

...
 92         while :; do
 93                echo -n '(I)nstall, (U)pgrade, (A)utoinstall or (S)hell? '
 94                read REPLY
...
120                !*)     eval "${REPLY#?}"
121                        ;;
122                esac
123         done
...

I just removed the whole part, and replaced it with:

/install -a -f /install.conf

So as soon as the machine will be booted, it will launch the install script in autoinstall mode (-a) with our specific answer file (-f install.conf).

###Automatically reboot at the end of the installation

Since we will not have acces to any console, we have to force the reboot of the machine at the end of the installation. To do this, we need to modify the file /usr/src/distrib/miniroot/install.sub where we will find the finish_up() function. Go to the end (line 2167), and add the reboot(8) command.

...
2163         [[ "$MODE" == upgrade ]] && \
2164                 echo "After rebooting, run sysmerge(8) to update your system configuration."
2165         $auto && >/ai.done
2166
2167         reboot
2168 }
...

Now the server will automatically reboot at the end of the installation.

###Build the image

First, go in /usr/src/distrib/special and build it:

# make clean
# make obj
# make
# make install

Then go in your distrib folder (/usr/src/distrib/amd64 in my case) and build the image with:

# make clean
# make obj
# make depend
# make

Take some time for you now, go make some tea, meditate. Obviously the times taken by those steps will depend of the power of your machine.

When the compilation end, you will find the miniroot55.fs file in your /usr/src/<your_distrib>/ramdisk_cd/obj/miniroot55.fs.

###Copy the miniroot & reboot your machine.

Now that you have your miniroot you have to dd it on the target hardware. This step will varies greatly depending of your hoster and or the machine itself.

If your server is hosted, the basic step are:

• Make your image available from somewhere over the network
• Boot your server in rescue mode
• Download your image, and dd it. Most of the time (on linux): dd if=miniroot55.fs of=/dev/sda
• Reboot your server

When the machine will reboot, it will boot in your miniroot images, launching the installation. This may take time, so do not stress and continue to drink your tea. At the end of the installation the machine will reboot, and you will have access to your ssh again ! (hopefully)

###Done

You are done. I do not know what you think, but to me as an OpenBSD noob, I found this easy enough to set up :)

##Pitfalls

• The install only use DHCP for the network, ensure that will not lockup your box
• Ensure all your hardware will be supported by the default kernel.
• In general, think before acting. Read this completely before doing it. (Yes, the fact that this is at the end, is a test ;))

##Contributing

I would love to have feedback on this, and learn new things about OpenBSD, do not hesitate to send me constructive criticism. I am pretty sure this whole things is far from perfect!

##Contact

• By twitter: @Mayeu
• By e-mail:
  • GPG key: A016 F2D8 0472 1186 1B33 A419 22B1 0496 B00D A693
  • Or see my webpage

##Ressources

• YAIFO WIP
• OpenBSD 5.5 Installation Guide
• OpenBSD - Building the System from Source
• OpenBSD - Disk Setup
• Automatic OpenBSD Installation
• autoinstall(8)
• Custom Kernel in OpenBSD bsd.rd
• Automatic, unattended OpenBSD installs with PXE