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This guide was validated using a Raspberry Pi 4 with Raspberry Pi OS Bookworm Legacy 64-bit Lite installed through Raspberry Pi Imager. The current TransSECS and MIX deployments were validated on this system using Java 25. Sections describing Raspberry Pi 5 hardware, command-line imaging, or MIX-specific network configuration are retained as reference information where noted but were not part of the Raspberry Pi 4 base-setup validation.

Current ErgoTech TransSECS and MIX deployments validated with this guide require Java 25.

The validated Raspberry Pi installation used Azul Zulu OpenJDK 25.0.3 for ARM64:

/opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64

Install the approved Java 25 ARM64 distribution under:

/opt/java

After installation, verify the Java executable directly:

/opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64/bin/java -version

The validated installation reports:

openjdk version "25.0.3"
OpenJDK Runtime Environment Zulu25.34+17-CA
OpenJDK 64-Bit Server VM Zulu25.34+17-CA

Also verify that the Java executable exists:

ls -l /opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64/bin/java

The deployment procedures select this Java installation explicitly.

For example, MIX uses:

MIX_JAVA_HOME=/opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64

TransSECS can select the same Java installation by placing its bin directory first in PATH:

PATH=/opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64/bin:$PATH

It is therefore not necessary for the Raspberry Pi's system-wide java command to be changed in order for MIX or TransSECS to use Java 25.

Java 8 is not installed as part of the current base setup. The current TransSECS deployment was tested with Java 8 and could not start because the deployed classes require Java 25.

Older ErgoTech software releases may have different Java requirements. Follow the release-specific installation instructions when maintaining an older system.

Reboot:

sudo reboot

After about a minute, reconnect with SSH and run:

/opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64/bin/java -version
cat /var/log/ergotech-boot-maintenance.log
df -h /
timedatectl
ip -br addr
ip route

Verify:

• Java 25 starts successfully from /opt/java/zulu25.34.17-ca-fx-jdk25.0.3-linux_aarch64.
• Java reports version 25.0.3 for the validated installation.
• The boot-maintenance log contains a new start and finish entry from the reboot.
• The root filesystem has plenty of free space.
• The system time and time zone are correct.
• The network interface intended for the installation is UP and has the expected IP address.
• The routing table contains the expected gateway.

Also verify that the startup-maintenance service completed successfully:

systemctl status rc-local.service --no-pager

It should show:

Active: active (exited)

For a Raspberry Pi 3 or 4, verify that the saved fake-hardware-clock value exists:

cat /etc/fake-hwclock.data

If a fixed IP address was configured, reconnect using that address after the reboot to confirm that the network configuration persisted.

At this point the SD card can be preserved as a completed base image before TransSECS or MIX is installed.

Before removing the SD card, shut the Pi down cleanly:

sudo shutdown -h now

Wait until the Raspberry Pi has fully shut down before removing power or the microSD card.

A Pi created from the image still needs the correct network settings and a unique hostname when several Pis share a network. Each individual system also requires its own ErgoTech license.