Documentation

Unattended Installation

kldload supports fully automated installs via an answers file — no web UI or user interaction required. Boot the ISO, and it installs to disk using pre-defined settings.

Works for CentOS/RHEL and Debian targets.

The answers file

The installer reads environment variables from a file. Create one:

cat > answers.env << 'EOF'
KLDLOAD_DISTRO=debian
KLDLOAD_DISK=/dev/vda
KLDLOAD_HOSTNAME=web-server-01
KLDLOAD_USERNAME=admin
KLDLOAD_PASSWORD=changeme
KLDLOAD_PROFILE=server
KLDLOAD_STORAGE_MODE=zfs
KLDLOAD_ZFS_ENCRYPT=0
KLDLOAD_NET_METHOD=dhcp
KLDLOAD_TIMEZONE=America/New_York
KLDLOAD_LOCALE=en_US.UTF-8
KLDLOAD_KEYBOARD_LAYOUT=us
EOF

All supported variables

Variable	Values	Default	Description
`KLDLOAD_DISTRO`	`centos`, `debian`, `rhel`, `rocky`	—	Target distro
`KLDLOAD_DISK`	`/dev/vda`, `/dev/sda`, etc.	—	Install disk
`KLDLOAD_HOSTNAME`	any hostname	`kldload-node`	System hostname
`KLDLOAD_USERNAME`	any username	`admin`	Admin user
`KLDLOAD_PASSWORD`	any string	—	User password
`KLDLOAD_PROFILE`	`desktop`, `server`, `core`	`desktop`	Install profile
`KLDLOAD_STORAGE_MODE`	`zfs`	`zfs`	Always ZFS
`KLDLOAD_ZFS_ENCRYPT`	`0`, `1`	`0`	Enable encryption
`KLDLOAD_NET_METHOD`	`dhcp`, `static`	`dhcp`	Network config
`KLDLOAD_NET_IP`	IP/CIDR	—	Static IP (if static)
`KLDLOAD_NET_GATEWAY`	IP	—	Gateway (if static)
`KLDLOAD_NET_DNS`	IP	—	DNS server (if static)
`KLDLOAD_TIMEZONE`	tz database name	`UTC`	Timezone
`KLDLOAD_LOCALE`	locale string	`en_US.UTF-8`	System locale
`KLDLOAD_KEYBOARD_LAYOUT`	`us`, `de`, etc.	`us`	Keyboard layout
`KLDLOAD_NVIDIA_DRIVERS`	`0`, `1`	`0`	Install NVIDIA (CentOS only)
`KLDLOAD_ENABLE_EBPF`	`0`, `1`	`0`	Install eBPF tools
`KLDLOAD_STORAGE_MANUAL`	`0`, `1`	`0`	Drop to shell for manual pool creation
`KLDLOAD_INFRA_MODE`	`standalone`, `cluster-manager`, `join`	`standalone`	Deployment mode
`KLDLOAD_HUB_LAN`	IP	—	CM IP (if join mode)

Run the install manually

From the live ISO command line:

kldload-install-target --config /path/to/answers.env

Inject the answers file into the ISO

Method 1: USB sidecar

Place answers.env on a second USB drive. The installer checks: - /run/kldload-answers.env - /mnt/answers.env - /etc/kldload/answers.env

# Format a small USB stick
mkfs.fat -F32 /dev/sdb1
mount /dev/sdb1 /mnt
cp answers.env /mnt/answers.env
umount /mnt

Boot the kldload ISO with the answers USB plugged in. The installer detects it automatically.

Method 2: Bake into the ISO

Add the file to live-build/config/includes.chroot/ before building:

cp answers.env live-build/config/includes.chroot/etc/kldload/answers.env
PROFILE=server ./deploy.sh build

Method 3: Kernel command line

Pass the config file path on the GRUB command line:

Edit live-build/config/includes.binary/EFI/BOOT/grub.cfg:

linuxefi /images/pxeboot/vmlinuz ... kldload.config=/etc/kldload/answers.env

Example: fleet of identical servers

Build 10 identical servers:

cat > answers.env << 'EOF'
KLDLOAD_DISTRO=centos
KLDLOAD_DISK=/dev/sda
KLDLOAD_USERNAME=admin
KLDLOAD_PASSWORD=fleetpass123
KLDLOAD_PROFILE=server
KLDLOAD_NET_METHOD=dhcp
KLDLOAD_TIMEZONE=UTC
EOF

Each server will get the same config except the hostname, which defaults to kldload-node. To set unique hostnames, either:

Use separate answers files per machine
Set the hostname after install via Salt/Ansible
Use a firstboot script that derives the hostname from the MAC address

Example: encrypted desktop

cat > answers.env << 'EOF'
KLDLOAD_DISTRO=debian
KLDLOAD_DISK=/dev/nvme0n1
KLDLOAD_HOSTNAME=dev-workstation
KLDLOAD_USERNAME=developer
KLDLOAD_PASSWORD=securepass
KLDLOAD_PROFILE=desktop
KLDLOAD_ZFS_ENCRYPT=1
KLDLOAD_NVIDIA_DRIVERS=0
KLDLOAD_ENABLE_EBPF=1
KLDLOAD_NET_METHOD=dhcp
KLDLOAD_TIMEZONE=America/Los_Angeles
EOF

Example: static IP server

cat > answers.env << 'EOF'
KLDLOAD_DISTRO=centos
KLDLOAD_DISK=/dev/sda
KLDLOAD_HOSTNAME=db-primary
KLDLOAD_USERNAME=admin
KLDLOAD_PASSWORD=dbpass
KLDLOAD_PROFILE=server
KLDLOAD_NET_METHOD=static
KLDLOAD_NET_IP=10.100.10.50/24
KLDLOAD_NET_GATEWAY=10.100.10.1
KLDLOAD_NET_DNS=1.1.1.1
KLDLOAD_TIMEZONE=UTC
EOF

Example: core (ZFS only, no extras)

cat > answers.env << 'EOF'
KLDLOAD_DISTRO=debian
KLDLOAD_DISK=/dev/sda
KLDLOAD_HOSTNAME=zfs-node
KLDLOAD_USERNAME=admin
KLDLOAD_PASSWORD=changeme
KLDLOAD_PROFILE=core
KLDLOAD_NET_METHOD=dhcp
KLDLOAD_TIMEZONE=UTC
EOF

This installs a stock Debian with ZFS on root, ZFSBootMenu, SSH, and networking. No k* tools, no web UI, no sanoid, no darksites. Manage everything with native zfs, zpool, apt/dnf commands.

Post-install automation

After the base install, kldload runs a firstboot service. You can hook into this:

# Create a post-install script
cat > live-build/config/includes.chroot/usr/local/sbin/my-firstboot.sh << 'SCRIPT'
#!/bin/bash
# Runs once after first boot

# Install additional packages
kpkg install htop tmux

# Configure NTP
timedatectl set-ntp true

# Start your application
systemctl enable --now myapp

# Remove this script after running
rm -f /usr/local/sbin/my-firstboot.sh
SCRIPT
chmod +x live-build/config/includes.chroot/usr/local/sbin/my-firstboot.sh

Wire it into the firstboot service or create a systemd oneshot:

cat > live-build/config/includes.chroot/etc/systemd/system/my-firstboot.service << 'EOF'
[Unit]
Description=Custom firstboot
After=network-online.target kldload-firstboot.service
Wants=network-online.target

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/my-firstboot.sh
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target
EOF

Rebuild the ISO to include it.

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