Changing data directory for postgres on CentOS
SELinux blocking access? Check your /var/log/audit/audit.log.

It might be necessary to fix the SELinux context for the new dir:

semanage fcontext --add --equal /var/lib/pgsql /home/mlu/postgres-data/pgsql
restorecon -rv /home/mlu/postgres-data/pgsql/