= asval =

 * Raspbian on RPi Model 3B+
 * debian stretch (9.11) x64
 * located at home

<<TableOfContents>>


== network ==

/etc/dhcpcd.conf uses a static IPv4 address at the bottom? But still apparently comes up like it's DHCP. The IPv6 stuff works at least.
{{{
slaac hwaddr

interface eth0
static ip_address=192.168.1.24/24
static routers=192.168.1.1
static domain_name_servers=8.8.8.8 1.1.1.1 8.8.4.4
}}}

Who even set this up? I don't remember doing it...


== IPv6 ==

Autoconfigured, slaac hwaddr, not externally accessible


== services ==

 * Unifi controller
 * Wireguard server to LAN for remote access
 * apt cache, will try running this setup for the crappy raspi repo: https://fabianlee.org/2018/02/11/ubuntu-a-centralized-apt-package-cache-using-apt-cacher-ng/

== wireguard ==

 * no notes on install
 * Proxy ARP enabled in sysctl.conf as per https://wiki.debian.org/BridgeNetworkConnectionsProxyArp {{{
net.ipv4.ip_forward=1
net.ipv4.conf.all.proxy_arp=1
}}}



== 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. Edit your /boot/config.txt and add: {{{
dtoverlay=disable-wifi
dtoverlay=disable-bt
}}}
  * The linked page above uses pi3-disable-foo, which are deprecated names
 1. Disable hciuart daemon used for bluetooth modem access {{{
systemctl disable --now hciuart
}}}


== RTC module ==

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, or do it yourself
  * Comment out any blacklist entries for i2c[-_]bcm2708 in /etc/modprobe.d/raspi-blacklist.conf
  * Add `i2c-dev` to /etc/modules
  * `dtparam=i2c_arm=on` in /boot/config.txt
  * Activate it now, `modprobe i2c-dev`
 1. Install packages {{{
apt install python-smbus i2c-tools
}}}
 1. Reboot now to detect it

 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
  * Append to end of /boot/config.txt {{{
dtoverlay=i2c-rtc,ds3231
}}}
 1. Reboot again
 1. Again detect the device on i2c bus: i2cdetect -y 1
  * Should appear at 0x68, BUT with "UU" at the address

 1. Remove the fake hardware clock {{{
systemctl disable fake-hwclock
apt purge fake-hwclock
}}}

 1. In theory everything just works now thanks to a udev rule
  * https://www.raspberrypi.org/forums/viewtopic.php?t=209700
  * /lib/udev/rules.d/85-hwclock.rules
  * KERNEL=="rtc0", RUN+="/sbin/hwclock --rtc=$root/$name --hctosys"
  * "Set the system time from RTC and set the kernel TZ to the local timezone when the kernel clock module is loaded"

 1. Your NTP daemon will handle writing the system clock back to the HW clock periodically. chrony is great, or you can use the simple systemd-timesyncd: https://www.raspberrypi.org/forums/viewtopic.php?t=200385
  * Purge chrony so that timesyncd will activate itself, and configure it in /etc/systemd/timesyncd.conf {{{
[Time]
NTP=ntp.on.net ntp.ubuntu.com 0.ubuntu.pool.ntp.org 1.ubuntu.pool.ntp.org 2.ubuntu.pool.ntp.org
}}}