After initializing the image, I need to reconfigure the database :

cd /opt/IBM/ldap/V6.3/sbin  
./idscfgdb -I ldapdb2 -a ldapdb2 -t ldapdb -l /home/ldapdb2

Stop the server

./ibmslapd -I ldapdb2 -k

Configure the suffix

./idscfgsuf -I ldapdb2 -s o=issc

Import

./idsldif2db -i /tmp/issc.ldif -I idsldap

Start the server

./ibmslapd -I ldapdb2