Dlink DNS-323, part 2 – JBOD vs separate disks

This is a continuation of a previous post.

With all my important data on another disk it was finally time to upgrade the DNS-323 to the newest firmware and to reformat the disks. This also brought up the question whether I should use JBOD or separate disks. After searching on the Internet, there seems to be a lack of evidence of just how the DNS-323 handles disks in a JBOD array. And so I wondered if maybe I should test and document it.

To do that I wrote the following little Bash script and run against the JBOD array from another computer. The script creates numbered files, each with a size of 1MB. 1000 such files are placed in each directory. The plan was to fill the entire disk and then take out the disks to study and see what the DNS-323 had stored on each disk and to verify that the content on a disk would in fact be accessible if the other disk broke down.

#!/bin/bash
 
TARGET=/mnt/nas
FOLDERS=500
FILES_PER_FOLDER=1000
BLOCKS_PER_FILE=2000
 
if [ ! -d $TARGET ]; then
  echo "Target folder does not exist"; exit
fi
 
for d in `seq 1 $FOLDERS`; do
  dirname=`printf 'D%07d' $d`
  echo "Creating folder: $dirname"
  mkdir $TARGET/$dirname
 
  echo " Creating file: F0000001"
  dd if=/dev/zero of=$TARGET/$dirname/F0000001 count=$BLOCKS_PER_FILE
  for f in `seq 2 $FILES_PER_FOLDER`; do
    filename=`printf 'F%07d' $f`
    echo " Copying file: $filename"
    cp $TARGET/$dirname/F0000001 $TARGET/$dirname/$filename
  done
 
done


Please check back for the result of these tests.