Emerald Reverie

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Updated Archlinux ISO Details

Sigh. Nothing stays still in the tech world, does it? :)

The Archlinux Releng team have drastically altered the method for installing Archlinux since I wrote my previous article. In particular, they have dropped AIF and resorted to simple bash commands for installation.

This actually makes our life for Foreman much easier, but I thought I should write a small blog post to tell you how to use it.

Installation Media

Not much changes here, except now you can use the default release images, from https://www.archlinux.org/download/

You will still need to loop-mount the iso for NFS or HTTP access and copy out the vmlinuz and archiso.img files though.

The /dev/vda problem seems to be gone now, hooray! Default-created libvirt guests from Foreman should work fine now, assuming you keep the “sed -i mkinitcpio.conf” change in the Finish template.

The script=… parameter in your PXElinux template remains the same, but at present there is a bug in the current release which prevents it working. The installer will boot to a root shell, at which point you have to manually install wget and run the foreman script:

    pacman -Sy wget
    wget -q -O /tmp/startup_script http://foreman/unattended/provision
    bash /tmp/startup_script

Once this bug has been fixed and should be released in the next stable iso. Or you can use https://wiki.archlinux.org/index.php/Archiso#Configure_our_live_medium to build your own ISO with wget in it - worked fine for me, with no cusomizations.

New Templates for New Times

The only real changes are what data we feed to Arch - it used to be AIF profile data, now it’s just a bash script. The installation is roughly 2 parts:

    1) Partitioning/mounting the disk and running pacstrap
    2) Chrooting into the install for everything else

So, as is fairly standard for Foreman, we can use a ‘provision’ type template for (1) and a ‘finish’ for (2). Let’s see an example:

Provision

# Simple script to provision new style Arch install

### Disk setup / mount
<%= @host.diskLayout %>
### End disk setup

# Base install
/usr/bin/pacstrap /mnt base

# Install Grub
/usr/bin/pacstrap /mnt grub-bios

# Fstab
/usr/bin/genfstab -p /mnt >> /mnt/etc/fstab

### Create finish script
/usr/bin/wget <%= foreman_url(“finish”) %> -O /mnt/bin/foreman.finish
/bin/chmod +x /mnt/bin/foreman.finish
/usr/bin/arch-chroot /mnt foreman.finish
rm /mnt/bin/foreman.finish

# Finish up
umount /mnt
/usr/bin/wget –quiet –output-document=/dev/null –no-check-certificate <%= foreman_url %>

# Reboot
/sbin/shutdown -r now

Finish

#Hostname
/bin/echo “<%= @host.shortname %>” > /etc/hostname

#Time
/bin/ln -snf /usr/share/zoneinfo/Europe/London /etc/localtime

#Locale
/bin/echo -e ‘LANG=”en_GB.UTF-8”\nLC_COLLATE=”C”’ > /etc/locale.conf
/bin/echo -e ‘en_GB.UTF-8 UTF-8’ > /etc/locale.gen
/usr/sbin/locale-gen

#Keymap
/bin/echo ‘KEYMAP=”uk”’ > /etc/vconsole.conf

#Mkinitcpio
/bin/sed -i ‘s/MODULES=.*/MODULES=”virtio_blk virtio_pci virtio_net”/’ /etc/mkinitcpio.conf
/usr/bin/mkinitcpio -p linux

#Grub
/sbin/modprobe dm-mod
/usr/sbin/grub-install –target=i386-pc –recheck /dev/vda
/bin/mkdir -p /boot/grub/locale
/bin/cp /usr/share/locale/en\@quot/LC_MESSAGES/grub.mo /boot/grub/locale/en.mo
/usr/sbin/grub-mkconfig -o /boot/grub/grub.cfg

#Passwd
/bin/echo ‘root:<%= root_pass %>’ | /usr/sbin/chpasswd -e

# Other stuff

# SSH
pacman -S –noconfirm openssh
/bin/sed -i ‘s/DAEMONS=(\(.*\))/DAEMONS=(\1 sshd)/’ /etc/rc.conf

# Yaourt repo
echo ‘[archlinuxfr]
Server = http://repo.archlinux.fr/$arch
SigLevel = Never’ >> /etc/pacman.conf

pacman -Sy –noconfirm yaourt base-devel

# Install stuff with yaourt
yaourt -Sy –noconfirm puppet

cat > /etc/puppet/puppet.conf << EOD
<%= snippets “puppet.conf” -%>
EOD
/usr/bin/touch /etc/puppet/namespaceauth.conf 
/usr/bin/puppet agent –config /etc/puppet/puppet.conf –onetime –tags no_such_tag –server <%= @host.puppetmaster %> –no-daemonize

Partition Table

# Blank the disk
/bin/dd if=/dev/zero of=/dev/vda count=1 bs=512

# Single partition
/bin/echo -e “n\np\n1\n\n\nw\n” | fdisk /dev/vda

# Format partition
/sbin/mkfs.ext4 /dev/vda1

# Mount partition
/bin/mount /dev/vda1 /mnt

Wrap up

So there you have it. You can install extra packages, configure services, etc at the end of the Finish script as per normal. Enjoy!