Installing MIX on a Raspberry Pi

Complete Raspberry Pi Base Setup first.

These instructions assume MIX is installed in:

/home/mix/mixruntime

The normal MIX web port is 7226 unless mix.port in mix.properties has been changed.

The normal addresses are:

http://<Pi-address>:7226
http://<Pi-address>:7226/setup.html

The first opens the application interface. The second opens the MIX setup page.

Install MIX using the ErgoTech MIX installation package or installation instructions.

When installation is complete, /home/mix/mixruntime should contain files including:

runmix.sh
mix.jar
mix.properties
log4j.mix.xml

Make the startup script executable:

chmod +x /home/mix/mixruntime/runmix.sh

Linux uses systemd to manage services. A MIX systemd service starts MIX automatically during boot and restarts it if the process stops.

MIX console output should also be redirected to its own file. This prevents Java console messages from filling Linux logs such as syslog and daemon.log.

Create the log directory:

mkdir -p /home/mix/mixruntime/logs

Create:

sudo nano /etc/systemd/system/mix.service

Paste:

[Unit]
Description=MIX Service
After=network-online.target
Wants=network-online.target
 
[Service]
User=root
WorkingDirectory=/home/mix/mixruntime
ExecStart=/bin/sh /home/mix/mixruntime/runmix.sh
Restart=always
RestartSec=60
StandardOutput=append:/home/mix/mixruntime/logs/runmix-console.log
StandardError=append:/home/mix/mixruntime/logs/runmix-console.log
 
[Install]
WantedBy=multi-user.target

Save with Ctrl+O, Enter, Ctrl+X.

Then:

sudo systemctl daemon-reload
sudo systemctl enable mix
sudo systemctl start mix
sudo systemctl status mix

Look for active (running). Press q to leave the status display.

Do not replace a working service file merely to add console logging.

First inspect it:

sudo systemctl cat mix.service

Create a systemd override directory:

sudo mkdir -p /etc/systemd/system/mix.service.d

This is the standard Linux location for local changes to an existing service. It keeps the original MIX service definition unchanged.

Create:

sudo nano /etc/systemd/system/mix.service.d/override.conf

Paste:

[Service]
StandardOutput=append:/home/mix/mixruntime/logs/runmix-console.log
StandardError=append:/home/mix/mixruntime/logs/runmix-console.log

Save with Ctrl+O, Enter, Ctrl+X.

Apply and restart:

sudo systemctl daemon-reload
sudo systemctl restart mix.service

Verify the complete effective configuration:

sudo systemctl cat mix.service

Run:

tail -n 20 /home/mix/mixruntime/logs/runmix-console.log

You should see MIX and Java startup messages.

It is normal for /var/log/syslog to continue containing Linux messages, for example network or WiFi status messages. The important result is which MIX and Java console output now appears in runmix-console.log rather than repeatedly filling the Linux system logs.

From a browser on a PC, open:

http://<Pi-address>:7226/setup.html

Click Get Pre-License Key.

Send the displayed pre-license key to ErgoTech.

The ErgoTech license is associated with the individual system. Changing the hostname, IP address, or network configuration does not change the license.

Copy the ErgoIOTLicense.lic file which ErgoTech provides into:

/home/mix/mixruntime

Then restart MIX:

sudo systemctl restart mix

Opening Get Pre-License Key also provides a convenient way to update the Raspberry Pi’s date and time. This is useful on systems which do not have access to a network time server.

The same setup page contains Network Configuration for systems which use MIX to manage the Pi’s network settings.

Create:

sudo nano /etc/logrotate.d/runmix-console

Paste:

/home/mix/mixruntime/logs/runmix-console.log {
    size 5M
    rotate 5
    compress
    delaycompress
    missingok
    notifempty
    copytruncate
    create 0644 root root
}

Save with Ctrl+O, Enter, Ctrl+X.

Check it:

sudo logrotate -d /etc/logrotate.d/runmix-console

A normal result mentions:

• /home/mix/mixruntime/logs/runmix-console.log
• 5242880 bytes, which is 5 MB
• 5 rotations

If the current file is smaller than 5 MB, logrotate will say the log does not need rotating. This is normal.

MIX.log is already limited by MIX’s log4j configuration and does not need this additional rule.

sudo reboot

After about a minute, reconnect and run:

systemctl status mix
tail -n 20 /home/mix/mixruntime/logs/runmix-console.log
df -h /
ls -lh /var/log/syslog*
ls -lh /var/log/daemon.log*
cat /var/log/ergotech-boot-maintenance.log

Verify:

• MIX is active (running).
• runmix-console.log contains recent MIX messages.
• The SD card has plenty of free space.
• syslog and daemon.log are bounded.
• The boot-maintenance log shows a successful run after the reboot.

If this SD card will become a master image, verify the complete system once more before imaging it.