Data corruption durning data xfer between PATA & SATA drives??

[stevecs]

Remember that the areca volume check is a raid-array verification. I.e. it DOES NOT VERIFY DATA. It verifies that the parity is the correct calculation of the bits in the data stripe width. Ie. It has no idea if the file itself is correct (it doesn't even know if a file or even a filesystem is there). It just sees if the bits match and if not (like with raid 3/4/5) is like flipping a coin, it will (usually user choice at check time) either 'assume' the data is good _or_ the parity is good and 'fix' the other. Which could actually be destroying it. Remember that RAID is for availability _not_ data integrity.

for a real-simple md5 check under linux you can use this early version of a script I have here (the current one is very convoluted and not generic enough to be of real use for you (like I said no time to really clean things up) ). Anyway it can get you started.

#!/bin/bash

##
# Filesystem MD5 Check (low level drive & file checking)
##
##
# Requirements:
#
# md5sum
# find
##

# Set argument variables & usage
MNTPNT=$1
CHECK=$2
IGNORE=$3

usage ()
{
        echo -e "usage: `basename $0` MOUNTPOINT [create|check] {IGNOREDIR}\n"
}

# Get arguments

if [ -z "${MNTPNT}" ]; then
        usage
        exit 1
fi



# Set static variables
CURDATE=`date +%Y%m%d`
OLDDATE=`date +%Y%m`"01"
OUTDIR="/var/log/md5sum"
OLDIFS="$IFS"
IFS="
"


# CHECK/Verify MD5SUM function
if [ "${CHECK}" = "check" ]; then
   if [ -f "$OUTDIR/md5sum.$OLDDATE" ]; then
      md5sum -c "$OUTDIR/md5sum.$OLDDATE" | grep -v ": OK" >> $OUTDIR/md5check.$CURDATE
   else
      echo "ERR: old md5sum file does not exist"
   fi
fi

# Create MD5SUM Function
if [ "${CHECK}" = "create" ]; then
   if [ -z "${IGNORE}" ]; then
      for FILE in `find "${MNTPNT}" -type f -print0 | xargs -0 -i echo -e -n "{}\n"` ; do
         md5sum -b "$FILE" >> $OUTDIR/md5sum.$CURDATE
      done
   else
      for FILE in `find "${MNTPNT}" -type f -print0 | xargs -0 -i echo -e -n "{}\n" | grep -v $IGNORE` ; do
         md5sum -b "$FILE" >> $OUTDIR/md5sum.$CURDATE
      done
   fi
fi

As for other tools, nothing really besides what you write yourself (or at least nothing that I've really found anywhere and that includes home, PC, workstation, midrange (unix/as400) and mainframes. The industry seems to really have blinders on and I have no idea why.

[Gogeta]

Thank you very much for sharing your code. It will definitely give me at least some peace of mind and hopefully a better understanding of the concepts.

When you mentioned the volume check earlier I assumed it was referring to an actual partition and not the RAID volume. Microsoft refers to partitions as volumes...MCSE training getting in the way again...

OT question: If I'm using 3 500GB disks on an ARC-1210 can I create two distinct arrays? For example, use 750GB as RAID-5 and 250GB as RAID-1? If its possible, what is the impact on performance? It seems like it would have to utilize the OS a lot more as it would deal directly with a file system or partition instead of just the block device as a whole.