Multiple Printers

Moonriver is designed to work efficiently with multiple printers using tools like GNU Parallel.

GNU Parallel

GNU Parallel is a shell tool for executing jobs in parallel.

Installation

# Debian/Ubuntu
sudo apt-get install parallel

# macOS
brew install parallel

# Fedora/RHEL
sudo dnf install parallel

Basic Parallel Usage

Run on Multiple Printers

# Home all printers in parallel
parallel moonriver --host {} --port 7125 G28 ::: printer1 printer2 printer3

Check Temperatures

# Check temperature on all printers
parallel moonriver --host {} --port 7125 M105 ::: \
    192.168.1.101 \
    192.168.1.102 \
    192.168.1.103

Execute Multiple Commands

# Home and check temperature
parallel moonriver --host {} --port 7125 "G28, M105" ::: \
    ender.local \
    prusa.local \
    voron.local

Parallel Options

Control Parallelism

# Run maximum 2 jobs in parallel
parallel -j 2 moonriver --host {} --port 7125 G28 ::: printer{1..10}

# Run all jobs in parallel
parallel -j 0 moonriver --host {} --port 7125 G28 ::: printer{1..10}

With Progress

# Show progress bar
parallel --bar moonriver --host {} --port 7125 G28 ::: printer{1..10}

# Show which printer is being processed
parallel --tag moonriver --host {} --port 7125 G28 ::: printer1 printer2 printer3

Error Handling

# Continue even if some jobs fail
parallel --keep-order --halt never moonriver --host {} --port 7125 G28 ::: printer{1..10}

# Stop all if one fails
parallel --halt now,fail=1 moonriver --host {} --port 7125 G28 ::: printer{1..10}

Advanced Examples

Printer Array

#!/bin/bash

# Define printer array
PRINTERS=(
    "printer1.local"
    "printer2.local"
    "printer3.local"
    "printer4.local"
    "printer5.local"
)

# Home all printers
echo "Homing all printers..."
parallel -j 0 --bar moonriver --host {} --port 7125 G28 ::: "${PRINTERS[@]}"

# Check temperatures
echo "Checking temperatures..."
parallel -j 0 --tag moonriver --host {} --port 7125 M105 ::: "${PRINTERS[@]}"

Maintenance Script

#!/bin/bash
# Daily maintenance for all printers

PRINTERS=(printer{1..10}.local)

echo "Starting daily maintenance..."

# Step 1: Home all printers
parallel -j 0 --bar --tag moonriver --host {} --port 7125 G28 ::: "${PRINTERS[@]}"

# Step 2: Run bed leveling
parallel -j 2 --tag moonriver --host {} --port 7125 BED_MESH_CALIBRATE ::: "${PRINTERS[@]}"

# Step 3: Save configuration
parallel -j 0 moonriver --host {} --port 7125 SAVE_CONFIG ::: "${PRINTERS[@]}"

echo "Maintenance complete!"

Pre-Print Setup

#!/bin/bash
# Prepare multiple printers for printing

PRINTERS=(
    "printer1.local:200:60"
    "printer2.local:210:70"
    "printer3.local:200:60"
)

prepare_printer() {
    IFS=':' read -r host extruder_temp bed_temp <<< "$1"
    
    echo "Preparing $host..."
    moonriver --host "$host" --port 7125 \
        "G28, M104 S$extruder_temp, M140 S$bed_temp, M109 S$extruder_temp, M190 S$bed_temp"
    
    echo "$host ready!"
}

export -f prepare_printer

parallel -j 0 --tag prepare_printer ::: "${PRINTERS[@]}"

Status Monitoring

#!/bin/bash
# Monitor all printers continuously

PRINTERS=(printer{1..5}.local)

while true; do
    clear
    echo "=== Printer Status $(date) ==="
    echo
    
    parallel -j 0 --tag moonriver --host {} --port 7125 M105 ::: "${PRINTERS[@]}"
    
    sleep 5
done

Load Balancing

Distribute work across printers:

#!/bin/bash
# Print multiple files across available printers

FILES=(model1.gcode model2.gcode model3.gcode model4.gcode)
PRINTERS=(printer1 printer2 printer3 printer4)

# Assign each file to a printer
for i in "${!FILES[@]}"; do
    file="${FILES[$i]}"
    printer="${PRINTERS[$((i % ${#PRINTERS[@]}))]}"
    
    echo "Assigning $file to $printer"
    # Your print start logic here
done

Parallel with Input File

Create a printer list file:

# printers.txt
printer1.local
printer2.local
printer3.local
printer4.local
printer5.local

Use it:

# Home all printers from file
parallel -a printers.txt moonriver --host {} --port 7125 G28

# With multiple commands
parallel -a printers.txt moonriver --host {} --port 7125 "G28, M105"

Example Script

See the included example script:

# View the example
cat examples/parallel_printers.sh

# Make it executable
chmod +x examples/parallel_printers.sh

# Run it (after editing for your printers)
./examples/parallel_printers.sh

Tips

Limit Parallelism

Don't overwhelm your network:

# Max 5 printers at a time
parallel -j 5 moonriver --host {} --port 7125 G28 ::: printer{1..20}.local

Tag Output

See which printer each message is from:

parallel --tag moonriver --host {} --port 7125 M105 ::: printer{1..5}

Output:

printer1	T:20.5 /0.0 B:21.1 /0.0
printer2	T:21.2 /0.0 B:20.8 /0.0
printer3	T:19.9 /0.0 B:21.5 /0.0

Timeout Protection

Set timeouts to prevent hanging:

parallel --timeout 60 moonriver --host {} --port 7125 G28 ::: printer{1..10}

Dry Run

Test without executing:

parallel --dry-run moonriver --host {} --port 7125 G28 ::: printer{1..5}

Without GNU Parallel

If GNU Parallel isn't available, use shell background jobs:

#!/bin/bash

PRINTERS=(printer1 printer2 printer3)

# Start all jobs in background
for printer in "${PRINTERS[@]}"; do
    moonriver --host "$printer" --port 7125 G28 &
done

# Wait for all to complete
wait

echo "All printers homed!"

Next Steps

• Scripting Mode - More automation examples
• Configuration - Set up aliases
• Examples - More scripts