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Update all content; add categories and move Tech, Games, Music to category taxonomy; add location taxonomy

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Eryn Wells 2022-10-12 10:55:50 -07:00
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content/blog/2020/10/boot-raspberry-pi-over-tftp.md
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@ -3,26 +3,30 @@ title: "Booting a Raspberry Pi Over TFTP"
date: 2020-10-13T08:31:52-07:00
draft: false
series: ["Raspberry Pi OS Development"]
tags: ["Tech"]
categories: ["Tech"]
tags: ["Raspberry Pi", "Networking"]
---
In order to do this, I modified the [EEPROM bootloader][eeprom] bootloader
according to the instructions in the Raspberry Pi documentation. That page is
also on [GitHub][eeprom-gh] which might be a more stable location. On Raspbian
on the RPi:
on the Raspberry Pi:
{{< figures/code lang=sh >}}
{{< figures/code >}}
```sh
fw=/lib/firmware/raspberrypi/bootloader/stable/pieeprom-2020-09-03.bin
rpi-eeprom-config $fw > ~/bootconf.txt
vi ~/bootconf.txt
rpi-eeprom-config --out ~/pieeprom-new.bin --config ~/bootconf.txt $fw
sudo rpi-eeprom-update -d -f ~/pieeprom-new.bin
sudo reboot
```
{{< /figures/code >}}
My updated bootconf.txt is:
My updated `bootconf.txt` is:
{{< figures/code lang=cfg >}}
{{< figures/code >}}
```cfg
[all]
BOOT_UART=1
WAKE_ON_GPIO=0
@ -33,6 +37,7 @@ TFTP_FILE_TIMEOUT=30000
ENABLE_SELF_UPDATE=1
DISABLE_HDMI=0
BOOT_ORDER=0xf412
```
{{< /figures/code >}}
I enabled UART debugging, and set the boot order to be: network `0x2`, SD card
@ -41,45 +46,51 @@ repeated if the bootloader is updated via apt.
I [enabled the TFTP server][mac-tftp] on my Mac:
{{< figures/code lang=sh >}}
{{< figures/code >}}
```sh
sudo launchctl load -F /System/Library/LaunchDaemons/tftp.plist
sudo launchctl enable System/com.apple.tftpd
sudo launchctl start com.apple.tftpd
```
{{< /figures/code >}}
I’m not sure if the `enable` command is actually necessary. This doesn't
actually start the `tftpd` daemon. Instead, macOS starts the daemon on demand
when it notices an incoming tftp request on the network. Don't be alarmed!
The tftp server looks for files to serve out of **/private/tftpboot**, and those
The tftp server looks for files to serve out of **`/private/tftpboot`**, and those
things need to be world `rwx`, i.e. `777`. By default (this is configurable) the
RPi queries for a directory named by its serial number.
Raspberry Pi queries for a directory named by its serial number.
{{< figures/code lang=sh >}}
{{< figures/code >}}
```sh
mkdir /private/tftpboot/$raspberry_pi_serial
chmod 777 /private/tftpboot
chmod -R 777 /private/tftpboot/*
```
{{< /figures/code >}}
RPi looks for files of various names in that directory, one in particular by the
name of **start.elf**.
Raspberry Pi looks for files of various names in that directory, one in
particular by the name of **`start.elf`**.
Next, I had to update my Ubiquiti router's DHCP server configuration (on the
command line) to pass a `tftp-server` parameter in the DHCP payload. This step
may be optional because you can also set `TFTP_IP` in the **bootconf.txt** above
may be optional because you can also set `TFTP_IP` in the **`bootconf.txt`** above
to specify the IP directly. On my router:
{{< figures/code lang=sh >}}
{{< figures/code >}}
```sh
configure
set service dhcp-server shared-network-name LAN subnet $lan_cidr_subnet tftp-server-name $ip_of_mac
commit
save
exit
```
{{< /figures/code >}}
I also gave my Mac a static IP, and renewed the DHCP lease so it took the new IP
to make the whole process a little more smooth. Now, it appears the RPi will
attempt a TFTP boot, and I see queries in the logs on my Mac.
to make the whole process a little more smooth. Now, it appears the Raspberry
Pi will attempt a TFTP boot, and I see queries in the logs on my Mac.
## Further Reading