Delan Azabani

First experiences with OpenBSD

 1688 words 9 min  home openbsd

Tired of the sluggishness of Windows on my laptop and interested in experimenting with a Unix-like that I haven't tried before, I gave OpenBSD a second shot after a brief stint on my netbook a couple of years back. Coming from exclusively using Gentoo, this seemed like a natural choice due to its minimalism and the shared roots between ports and portage. Reading Matthew D. Fuller's comparison of BSD and Linux inspired me to venture beyond the familiar walls of the Linux world.

It would be prudent to start with a hint of background. I first discovered Linux via a cover disc on the APC magazine which included a live image for Mandriva Linux 2006.0. Until then, I had been using Windows XP, Windows 98 and Windows 95 in reverse order. While I dabbled with it, the concept of actually installing something that wasn't Windows on my computer never crossed my mind.

In 2009, I installed Ubuntu 9.04 cold turkey and continued using it for nearly two years, at which point I distro-hopped to Debian. For the entirety of 2012, I used Gentoo and I even had a small distcc cluster, but I eventually became annoyed at the poor quality of Linux userland software. From then until now, I had returned to Windows 7 with a sometimes painful drop of Cygwin where I needed a Unixish environment.

Creating an installation medium

I'm currently using an Asus U31SD which has no optical disc drive, calling for the use of a USB flash drive. I wanted to partition my large flash drive such that I could use it simultaneously as installation media and a backup destination. This was not trivial to configure in a way compatible with Windows.

Windows makes an arbitrary, silly distinction whereby it tries very hard to avoid partitioning 'removable disks', a category which includes USB flash drives, but not USB portable hard drives. Using diskmgmt.msc, diskpart or any stock GUI tool will create a partition table if the disk has no recognisable volume or partition table, but will only allow one partition to be created. Behold the idiocy:


DiskPart succeeded in cleaning the disk.

DISKPART> convert mbr

DiskPart successfully converted the selected disk to MBR format.

DISKPART> create partition primary size=4096

DiskPart succeeded in creating the specified partition.

DISKPART> create partition primary size=4096

No usable free extent could be found. It may be that there is insufficient
free space to create a partition at the specified size and offset. Specify
different size and offset values or don't specify either to create the
maximum sized partition. It may be that the disk is partitioned using the MBR disk
partitioning format and the disk contains either 4 primary partitions, (no
more partitions may be created), or 3 primary partitions and one extended
partition, (only logical drives may be created).


DiskPart succeeded in cleaning the disk.

DISKPART> convert gpt

DiskPart successfully converted the selected disk to GPT format.

DISKPART> create partition primary size=4096

DiskPart succeeded in creating the specified partition.

DISKPART> create partition primary size=4096

Virtual Disk Service error:
The operation is not supported on a non-empty removable disk.

If the disk has a direct volume with no partition table, Windows will roll with that and pretend that there is one partition. If multiple partitions are created on a disk elsewhere, its behaviour on Windows appears to be unpredictable, but it looks like a drive letter can be assigned to the first partition entry in the MBR, depending on the phase of the moon.

There is allegedly a 'removable media bit' in some drive controllers which can be flipped by a tool for Lexar drives called BootIt. Sadly it appeared to have no effect on my 64 GB Corsair drive. I tried creating many partition configurations using OpenBSD's own fdisk in a virtual machine, as well as GNU fdisk and parted on Debian. None of them played nicely with Windows. All I wanted was an NTFS or FAT32 partition plus a BSD disklabel.

What did work was dumping the contents of install55.fs or miniroot55.fs onto the entire drive, then adding another partition on entry 0 from there. These files contain not only a BSD disklabel with one root FFS, but ostensibly also an MBR surrounding that.

# ftp
# dd if=install55.fs of=/dev/rsd0c bs=65536
# echo 'e 0\n7\nn\n491520\n123043840\nw\np\nq' | fdisk -e sd0 | sed ':a;$q;N;6,$D;ba'
 0: 07     30 151  58 -   7689 183  46 [      491520:   123043840 ] NTFS
 1: 00      0   0   0 -      0   0   0 [           0:           0 ] unused
 2: 00      0   0   0 -      0   0   0 [           0:           0 ] unused
 3: A6      0   1   2 -     30 151  57 [          64:      491456 ] OpenBSD
fdisk: 1> #
# echo 'SCSI\nA\nw\np\nq' | disklabel -E sd0 | sed ':a;$q;N;5,$D;ba'
  a:           491456               64  4.2BSD   2048 16384    1 # /
  c:        123535360                0  unused
  i:        123043840           491520    NTFS
> No label changes.

It's perhaps here that I should mention that I found OpenBSD's distinction between block devices (for disks, partitions and slices) and their corresponding raw character device files quite bizarre. I suppose I just need to remember to prepend r to any administrative task pertaining to partitioning or filesystem creation.

The installation process proper

This was actually relatively straightforward, save for the wireless NIC iwn0 not working until firmware files are automatically downloaded after installation. Using the wired alc0 gigabit Ethernet interface temporarily did the trick, but networking was not even necessary at this stage, given that I had used the full install55.fs image.

iwn0: error, 2, could not read firmware iwn-6030
iwn0: could not read firmware
iwn0: no link ............. sleeping

First boot was problematic, as the kernel hung on something ACPI:

cpu3: smt 1, core 1, package 0
ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 20, 24 pins
acpiec0 at acpi0
acpihpet0 at acpi0: 14318179 Hz
acpimcfg0 at acpi0 addr 0xe0000000, bus 0-63

A quick and dirty solution I'm using right now is to disable it:

boot> -c
UKC> disable acpi
352 acpi0 disabled
UKC> quit

At this point I had to start over because I foolishly elected to start xdm(1) on boot, leaving me unable to use the keyboard or mouse. Choosing the right option, I am now greeted with an odd monospaced serif console. I then disabled ACPI permanently:

# cp /bsd{,.old}
# echo quit | config -efu /bsd

I missed the automatic firmware installation on first boot, so I had to invoke the process manually:

# echo dhcp > /etc/hostname.alc0
# . /etc/netstart alc0
# fw_update

Configuring a connection to my wireless network revealed the elegant nature of hostname.if(5), which strongly reminded me of the file format used with iptables-{save,restore}(8). It looks like connecting to Curtin University's network might need wpa_supplicant(8), however.

# echo 'nwid deLAN\nwpakey REDACTED\ndhcp\nrtsol' > /etc/hostname.iwn0
# . /etc/netstart iwn0

Some sysctl values prevent global IPv6 address configuration from working automatically, but after my surprise upon seeing the default values, they were quickly fixed:

# ifconfig iwn0 | grep inet6
        inet6 fe80::b6b6:76ff:fe1e:7bfc%iwn0 prefixlen 64 scopeid 0x1
# rtsol iwn0
rtsol: kernel is configured not to accept RAs
rtsol: kernel is configured not to accept redirects
# sed -E 's/^#(net.inet6.(icmp6.rediraccept|ip6.accept_rtadv)=)/\1/' /etc/sysctl.conf > /etc/sysctl.conf.
# mv /etc/sysctl.conf{.,}
# sysctl net.inet6.icmp6.rediraccept=1
# sysctl net.inet6.ip6.accept_rtadv=1
# rtsol iwn0
# ifconfig iwn0 | grep inet6
        inet6 fe80::b6b6:76ff:fe1e:7bfc%iwn0 prefixlen 64 scopeid 0x1
        inet6 2001:44b8:6116:1c00:b6b6:76ff:fe1e:7bfc prefixlen 64 autoconf pltime 3593 vltime 7194
        inet6 2001:44b8:6116:1c00:4487:8545:2941:c33c prefixlen 64 autoconf autoconfprivacy pltime 3593
vltime 7194

Getting X11 working

Upon trying to run Xorg -configure, it turns out that the problems I had been having with X11 seem to stem from the pms driver which is used for the Synaptics touchpad. For now, I'll simply disable the driver and use an external USB mouse as a pointing device.

boot> -c
UKC> disable pms
259 pms* disabled
UKC> quit
# echo quit | config -efu /bsd

Finishing user configuration

All that's left is to download my dotfiles and install some packages.

# sed -E 's/^# (%wheel.+\) SETENV.+)/\1/' /etc/sudoers > /etc/sudoers.
# mv /etc/sudoers{.,}
# chmod 440 /etc/sudoers
$ export PKG_PATH=
$ sudo pkg_add -v zsh vim curl git irssi gnupg ...
$ git clone --bare .git
$ sed -E 's/(bare = )true/\1false/' .git/config > .git/config.
$ mv .git/config{.,}
$ git checkout HEAD
$ chsh -s zsh
$ exec zsh

Miscellaneous thoughts

I very much appreciated the clean separation between the base system, the packages and the ports tree, and grew to rely on having an eloquent manual page for every command, driver and configuration file in the base system.

I don't know how I have managed to achieve this, but I can use vim key bindings in GUI applications, including those that use GTK+. Perhaps it is influenced by running bindkey -v in my .zshrc. was very useful for when I couldn't recall the exact name of a package I was looking for. In the long run however, it was much better to fetch and configure the ports tree locally as recommended. This also buys one the ability to cleanly configure and compile software from source, which is especially useful for dwm, for example.

Using pkg_info -t is a useful way of finding packages that one has explicitly installed so far:

neptune% pkg_info -t         
ImageMagick- image processing tools
chromium-32.0.1700.102-proprietary Chromium browser
dwm-6.0             dynamic window manager
git-         GIT - Tree History Storage Tool
gnupg-2.0.22p0      gnu privacy guard - a free PGP replacement
irssi-0.8.15p5      modular IRC client with many features (ipv6,socks,proxy)
iwn-firmware-5.10p0 firmware binary images for iwn(4) driver
p7zip-9.20.1p0      file archiver with high compression ratio
povray-3.6.1p5      3D image rendering package
scrot-0.8p3         commandline screen capture util
texlive_texmf-full-2013 texlive texmf for extra macros
uvideo-firmware-1.2p1 firmware binary images for uvideo(4) driver
vim-7.4.135p0-no_x11 vi clone, many additional features
zip-3.0             create/update ZIP files compatible with PKZip(tm)
zsh-5.0.2           Z shell, Bourne shell-compatible

In broad strokes, the tasks I have yet to complete are: