Setting up Raspberry Pi has changed a bit since when I first used it, and most of search results on the web describe steps applicable to Raspbian versions before Raspbian Bullseye (released in April 2020).

Specifically, before Raspbian Bullseye you could run ssh pi@raspberrypi and use the default password raspberry. Now, you need to generate the password using openssl.

Here are the newest (as of 2022) steps needed to get set up a headless Raspberry pi, specifically with Raspbian Bullseye (released on April 2020) and later:

Generate the password

• In unix terminal run the following command, using your password:

$ echo 'password' | openssl passwd -6 -stdin
$6$k5M8bJM8sciQg4N4$8STzoHVsSyzdjpzjuUhn6UDhxcbe/JlQB4WUbEBPl/1kIRBd8q3QA.I4h6hGCEdACLgt3ejDQj4qJIxNohOts0

Setup the headless raspberry pi

• Download Raspberry Pi OS Lite
• Use Etcher) to flash downloaded .zip onto a MicroSD card
• After flashing, open the FAT partition as folder in your code editor, and:
  • Create file named ssh. Keep it empty.
  • Create file named wpa_supplicant.conf and insert, replacing values of ssid and psk

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=US

network={
     ssid="ssid name"
     psk="password"
     scan_ssid=1
}

• Create file named userconf with the following content username:encrypted-password, replacing encrypted-password with the output of the above openssl command.

First boot

• Insert MicroSD in Raspberry Pi and power it up
  • If you see an error about tampering with fingerprint, open ~/.ssh/known-hosts and remove line containing raspberry, that’s from another device.
• Run sudo raspi-config to configure the hostname, timezone, and other relevant settings.
  • When quitting, you’ll be prompted to restart.
• When Rapsberry Pi reboots, connect using new hostname, e.g. ssh pi@newhostname
• Change password passwd pi
• Update sources of available packages sudo apt update
• Upgrade installed packages sudo apt full-upgrade