## page was renamed from servers/asval
= asval =

 * RPi Model 3B+ (aarch64, 4-core, 1gb RAM)
 * RPi OS Lite 64-bit (Bookworm)
 * LAN MAC `b8:27:eb:8c:f4:f8`
 * located at home

<<TableOfContents>>

== Build notes ==

This is the most generic stuff to do for initial setup, before tweaking it to a specific use.

=== OS imaging ===

Using the Raspberry Pi Imager app, start with '''RPi OS Lite 64-bit''', suitable for the RPi 3B+

It lets you make some customisations before flashing, which is really nice:
 * Set hostname to asval
 * Enable SSH
  * Password auth (I would use SSH keys but it didn't work right for me and I couldn't sudo later)
 * Set username and password
  * `pi // <something new>`
 * No WLAN
 * Set locale to Australia/Sydney, us keyboard
 * Disable telemetry

Prepare DHCP server with static address for the LAN MAC address.

Put in the card and let it boot, should be fairly quick.

=== First login ===
 1. Login as `pi@asval` and copy your SSH key there
 1. sudo up and copy your SSH key to root's account as well
 1. Login again directly as root
 1. Install base packages {{{
apt install -y vim git screen ack
}}}
 1. Edit `/etc/pam.d/sshd` and remove `user_readenv=1`, this will keep the logs tidy
 1. Configure vim {{{
cat <<EOF > ~/.vimrc
set nocompatible
syntax on
set background=dark
set hlsearch
set modeline
set scrolloff=3
EOF
}}}
 1. Configure shell
  * Edit `/root/.bashrc` to enable colours
  * Set the default editor to vim.basic: {{{
update-alternatives --config editor
}}}


=== Disable wifi and bluetooth on RPi ===

I'm using asval as a network appliance, so I don't need the radios: https://sleeplessbeastie.eu/2018/12/31/how-to-disable-onboard-wifi-and-bluetooth-on-raspberry-pi-3/

 1. Add dtoverlays to your `/boot/config.txt` to disable the radios: {{{
cat <<EOF >> /boot/config.txt
dtoverlay=disable-wifi
dtoverlay=disable-bt
EOF
}}}
 1. Disable the hciuart daemon used for bluetooth modem access {{{
systemctl disable --now hciuart
}}}
 1. Reboot


=== Configure hardware RTC ===

I've installed the Jaycar XC-9044 RPi realtime clock RTC, it's apparently a good clock chip with a little battery (or something). Most models using this chip have a spot for a watch battery, but this one has a tiiiiny little thing soldered on the board. I hope it's decent.

 1. Physically install the module on the 3V3 plus I2C pins
 1. Enable i2c with `raspi-config`, it's in `Interface Options -> I2C -> Enable`
  * You can also do it yourself if you want:
   1. Comment out any blacklist entries for `i2c[-_]bcm2708` in `/etc/modprobe.d/raspi-blacklist.conf`
   1. Load the module at boot: {{{
echo i2c-dev >> /etc/modules
}}}
   1. Uncomment/add `dtparam=i2c_arm=on` in `/boot/config.txt`
   1. Activate it now: {{{
modprobe i2c-dev
}}}
 1. Reboot now, it can't hurt
 1. Install i2c tools {{{
apt install -y i2c-tools
}}}
 1. Detect the device on i2c bus: `i2cdetect -y 1`
  * Should appear at 0x68
 1. Enable the kernel driver for it, or something, by adding a devicetree overlay {{{
echo "dtoverlay=i2c-rtc,ds3231" >> /boot/config.txt
}}}
 1. Reboot again to load the device tree overlay that we just configured
 1. Again detect the device on i2c bus: `i2cdetect -y 1`
  * Should appear at 0x68, BUT with "UU" at the address this time
 1. Remove the fake hardware clock {{{
systemctl disable fake-hwclock --now
apt purge -y fake-hwclock
}}}
 1. In theory everything just works now thanks to a udev rule: https://www.raspberrypi.org/forums/viewtopic.php?t=209700 {{{
root@asval:~# cat /lib/udev/rules.d/85-hwclock.rules
# Set the System Time from the Hardware Clock and set the kernel's timezone
# value to the local timezone when the kernel clock module is loaded.
KERNEL=="rtc0", RUN+="/usr/lib/udev/hwclock-set $root/$name"
}}}
 1. Install chrony so it manages the hardware clock {{{
apt install -y chrony
}}} It'll do the rest once it's installed and synced. Try some commands to see how it's fairing: {{{
chronyc sources
chronyc tracking
}}}