This chapter contains a guide to migrate a classic SE to dCache.

The convertion of a classic SE to dCache is not complicated, but has to be done very carefully to prevent data losses.

We assume, that dCache is installed and configured.( the section called “Installing a Single Node dCache Instance”). To be on the safe side, we recommend to install a new pool on a different host, since there is no easy way to switch back to classic SE.

The newly migrated files shall be available already.

#!/bin/sh

if [ $# -ne 3 ]
then
   echo "Usage: $0 <file> <pnfs path> <pool base>"
   exit 1;
fi

SRC=$1
FILE=`basename $1`
DIR=`dirname $1`
PNFS_PRFIX=$2
POOL_BASE=$3

PNFS_FILE="${PNFS_PRFIX}/${DIR}/${FILE}"

if [ ! -f "${SRC}" ]
then
   echo "File ${SRC} do not exist."
   exit 1
fi

if [  -f "${PNFS_FILE}" ]
then
   echo "File ${PNFS_FILE}  already exist."
   exit 2
fi

if [ ! -d "${POOL_BASE}/control" ]
then
   echo "Creating directory [control]"
   mkdir ${POOL_BASE}/control
fi

if [ ! -d "${POOL_BASE}/data" ]
then
   echo "Creating directory [data]"
   mkdir ${POOL_BASE}/data
fi

if [ ! -f "setup" ]
then
   echo "Creating dummy [setup] file"
   touch  ${POOL_BASE}/setup
fi

echo "Creating file in pnfs"
if [ ! -d ${PNFS_PRFIX}/${DIR} ]
then
   mkdir -p ${PNFS_PRFIX}/${DIR} > /dev/null 2>&1
   if [ $? -ne 0 ]
   then
      echo "Failed to create directory ${PNFS_PRFIX}/${DIR}"
      exit 3;
   fi
fi

touch ${PNFS_FILE}
FILE_SIZE=`stat -c "%s" ${SRC}`
touch "${PNFS_PRFIX}/${DIR}/.(fset)(${FILE})(size)(${FILE_SIZE})"
chmod --reference=${SRC} ${PNFS_FILE}
chown --reference=${SRC} ${PNFS_FILE}

echo "Creating control file for pnfsID $PNFS_ID"
PNFS_ID=`cat "${PNFS_PRFIX}/${DIR}/.(id)(${FILE})"`
echo "precious" >  ${POOL_BASE}/control/${PNFS_ID}
echo "Copy ${SRC} to  ${POOL_BASE}/data/${PNFS_ID}"
cp  ${SRC}  ${POOL_BASE}/data/${PNFS_ID}

exit 0