You can obtain OpenLDAP Software from the project's download page at https://www.openldap.org/software/download/ or directly from the project's FTP service at ftp://ftp.openldap.org/pub/OpenLDAP/.
The project makes available two series of packages for general use. The project makes releases as new features and bug fixes come available. Though the project takes steps to improve stability of these releases, it is common for problems to arise only after release. The stable release is the latest release which has demonstrated stability through general use.
Users of OpenLDAP Software can choose, depending on their desire for the latest features versus demonstrated stability, the most appropriate series to install.
After downloading OpenLDAP Software, you need to extract the distribution from the compressed archive file and change your working directory to the top directory of the distribution:
gunzip -c openldap-VERSION.tgz | tar xf -
You'll have to replace VERSION with the version name of the release.
You should now review the COPYRIGHT, LICENSE, README and INSTALL documents provided with the distribution. The COPYRIGHT and LICENSE provide information on acceptable use, copying, and limitation of warranty of OpenLDAP Software. The README and INSTALL documents provide detailed information on prerequisite software and installation procedures.