→ Applies to: SynetoOS 5.x

IMPORTANT
The following script creates 100 files simultaneously (each file will be 100MB) and it will write a total of 10GB per pool in one burst. Once finished, it logs the results in /tmp/dd_stress.log and deletes all the created files.

Step 1. Connect to SynetoOS appliance via SSH as admin

ssh admin@<your_ip_address_or_hostname>

Step 2. Get root privileges

sudo su -

Step 3. Edit /tmp/heavy-dd-zfs.sh file

vi /tmp/heavy-dd-zfs.sh

IMPORTANT
Make sure to copy and paste the exact lines below (replace <pool_name> with the correct pool name)

#!/bin/bash

POOL="<pool_name>/syn-volumes"
NUM_FILES=100
FILE_SIZE_MB=100    # Each created file size
BLOCK_SIZE=1M
BASE_DIR="/"
LOG="/tmp/dd_stress.log"

echo "Starting stress test with dd - $(date)" > "$LOG"

TARGET_DIR="${BASE_DIR}${POOL}/dd-stress"
mkdir -p "$TARGET_DIR"
echo "▶️ Write on $POOL ($TARGET_DIR)" | tee -a "$LOG"

# High intensity writing in parralel
for i in $(seq 1 $NUM_FILES); do
    FILE="$TARGET_DIR/file_$i.bin"
    dd if=/dev/urandom of="$FILE" bs=$BLOCK_SIZE count=$FILE_SIZE_MB > /dev/null 2>&1 &
done

# Waiting for all writing to be done
wait
echo "✅ Write completed on $POOL" | tee -a "$LOG"

# Deletion of generated files
echo "🧹 Cleanup files on $POOL" | tee -a "$LOG"
rm -f "$TARGET_DIR"/*.bin
echo "✅ Cleanup completed on $POOL" | tee -a "$LOG"

echo "✔️ Stress test completed - $(date)" | tee -a "$LOG"

Save and EXIT

:wq

Step 4. Give permissions to /tmp/heavy-dd-zfs.sh file

chmod +x /tmp/heavy-dd-zfs.sh

Step 5.  Run the script

/tmp/heavy-dd-zfs.sh

Step 6 (optional). Schedule script periodically

crontab -e

IMPORTANT
Make sure to add the line below as the last line in crontab file (replace <time> with how often to run in minutes, <path to script> with the path of the script and <path to log file> with the path to the log file)

*/<time> * * * * /usr/bin/bash -lc '<path to script> >> <path to log file> 2>&1'

EXAMPLE

*/5 * * * * /usr/bin/bash -lc '/tmp/heavy-dd-zfs.sh >> /tmp/dd_stress.log 2>&1'

Save and Exit

Ctrl + X

Step 7 (optional). Delete the schedule

crontab -e

IMPORTANT
Make sure to delete the previously added line in crontab file or add “#” at the start of the line

EXAMPLE

# */5 * * * * /usr/bin/bash -lc '/tmp/heavy-dd-zfs.sh >> /tmp/dd_stress.log 2>&1'

Save and Exit

Ctrl + X