Samba4 built on Centos 6 using list of dependances listed on https://wiki.samba.org/index.php/Samba_4_OS_Requirements
This does not include openldap-devel
it built & installed ok, but the nmbd,smbd,winbindd fileserver would not join the AD domain
'net ads join -U Administrator@HOME.LAN' gets this:
'ADS support not compiled in'
The issue here is that unlike the promise in BUILD_SYSTEMS.txt, we do not require this library by default, but instead silently degrade to not building with 'ads' support.
We should instead fail, but allow a build --without-ads-support.
Fixed in Samba 4.1 with 8d6bc9987c22248453c0acd25616eda35d6d99db