[Samba] No builtin nor plugin backend for ldapsam found

[Francesco Malvezzi]

[...]
>>> This will get you samba 4.1.17
>> that could be fine, but I have already samba installed in /opt and I
>> would like to install side-by-side samba3 and samba4.
> 
> To what end? you cannot run two instances of samba at the same time
> without jumping through hoops.

A Debian install is going to put directories, executables and state file
all over file system. A custom install with $PREFIX=/opt/samba4 is
easier to match with the current running installation of samba3 which is
in /opt/samba

> 
>>
>> But I understand it takes a lot of time to debug my faulty installation.
> 
> What is wrong with your existing installation ?

What was faulty was my compilation of samba4 which lacked ldapsam support.

Actually it was a stupid mistake. Sometime in the past I added
/opt/samba/lib (the samba3 install directory) to the ldconfig.
Removing that directory, samba4 compiles, make and installs fine with
ldapsam.

thank you,

Francesco