Open Infrastructure

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h1. Managing OpenWRT

h2. Installing and configuring Jool

* You can use one of the known NAT64 prefixes from our networks (LINK!)

** In the example below this is 2a0a:e5c0:2:10::/96

* You need to have a /96 (or better: /64) routed to the openwrt

** In the example below this is 2a0a:e5c0:17:1::/96

<pre>

opkg install kmod-jool

opkg install jool-tools

# Load the kernel module

modprobe jool_siit

# The range which will be the target for the 2nd NAT (if needed to reach a v4 ip)

jool_siit -6 2a0a:e5c0:2:10::/96

# Pick a v6 range to translate TO and a v4 range to translate from

jool_siit -e -a 2a0a:e5c0:17:1::/96 192.168.61.0/24

# Accept Router Advertisements to keep the default address

sysctl -w net.ipv6.conf.all.accept_ra=2

sysctl -w net.ipv6.conf.default.accept_ra=2

sysctl -w net.ipv6.conf.eth0.accept_ra=2

sysctl -w net.ipv6.conf.br-lan.accept_ra=2

</pre>

h2. Enabling routing with router advertisements

* By default ipv6 forwarding is on (good!)

* By default accept_ra is 0

** This does not set the route properly into the kernel -> routing is broken

* Need to modify accept_ra to 2

h2. Enabling SSH access on wan 

Enable it in the web interface

<pre> $URL/cgi-bin/luci/admin/system/admin/dropbear </pre>

OR

Dropbear uci var (not tested):

<pre>	option GatewayPorts 'on' </pre>

h2. Resetting to factory default

* See https://openwrt.org/docs/guide-user/troubleshooting/failsafe_and_factory_reset

<pre>

firstboot -y && reboot now

</pre>

h2. Installing and configuring an APU as a PIB with OpenWRT

* Get the x86 64 SQUASHFS image

** https://downloads.openwrt.org/releases/19.07.3/targets/x86/64/

** combined-squashfs.img.gz

* Gunzip it

* dd it it an usb stick

* Boot the usb stick on the APU

* When booted, wget it on the APU and write it over /dev/sda

<pre>

wget ... -O - | gunzip > /dev/sda

</pre>

* Configure it using pib-setup.sh from ungleich-tools

* Create a network on the VPN server

h3. Installing openwrt (squashfs) on APU details

<pre>

opkg update

</pre> 

* Install SSL certifaicates

<pre>

opkg install libustream-openssl ca-bundle ca-certificates

</pre> 

* check the time and date if it is not correct, modify the time and date as follows 

<pre>

date -s YEARMONTHDATETIME 

</pre>

* Flashing the squashfs openwrt image into the APUs SSD (adjust to the correct version)

<pre>

wget -O - http://downloads.openwrt.org/releases/19.07.3/targets/

x86/64/openwrt-19.07.3-x86-64-combined-squashfs.img.gz | gunzip > /dev/sda 

</pre>

h3. Defaults after Openwrt installation 

* eth0 = WAN

* eth1&2 = LAN

h2. Setting up the GL-INET GL-MT300N-V2

* Go to advanced and flash the standard image

* Link: https://openwrt.org/toh/gl.inet/gl.inet_gl-mt300n_v2

h2. Managing QMI based LTE devices

Debug commands:

<pre>

uqmi -d /dev/cdc-wdm0 --get-signal-info

uqmi -d /dev/cdc-wdm0 --get-data-status

uqmi -d /dev/cdc-wdm0 --get-current-settings

uqmi -d /dev/cdc-wdm0 --get-capabilities

uqmi -d /dev/cdc-wdm0 --get-imei

</pre>

* See also: https://openwrt.org/docs/guide-user/network/wan/wwan/ltedongle

h2. Managing static IPv6 addresses

If using a statically routed IPv6 network, the default RA mechanism does not set an outgoing route by default. This is a bit different from "regular" Linux:

* openwrt uses user space odhcp6c

* for openwrt we need to setup a "static default route"

** do not forget to select the interface in the list

* Default Linux on the other hand needs to use accept_ra=2 if ipv6 forwarding is on

** This also works on openwrt, but it is conflicting/not the correct way to do

* **TL;DR If using openwrt with static IPv6 addresses, add a static IPv6 default route**

Alternative (currently untested) approach:

<pre>

instead of hardcoding the subnet in lan, add it as "option ip6prefix" to your wan6/dhcpv6 interface

in lan merely add "option ip6assign 64" or however much bits you want to redelegate

that should make odhcp6c/netifd aware of the additional prefix and factor that into the default route coverage

it should work as if the prefix were received via dhcpv6-pd

</pre>

(Thanks to jow in #openwrt)

h2. Temperature sensor support

We are using "temper" based usb temperature sensors. They are read using "temper-py":https://pypi.org/project/temper-py/. 

The default setup is to write to /www/temperature.txt which allows the temperature to be read from the standard webserver.

So if you own a VIIRB/VIWIB/other OpenWRT device using the "openwrt-add-temper":https://code.ungleich.ch/ungleich-public/ungleich-tools/-/blob/master/openwrt-add-temper.sh you can see the temperature on http://ip-of-the-device/temperature.txt.

It is refreshed every 5 minutes.