"Authentication failure" on Ubuntu 18.04...

[Robert Heller]

I have a server running CentOS 6 on the bare metal, running the stock CentOS 6
OpenLDAP packages (openldap-2.4.40-16.el6.x86_64,
openldap-clients-2.4.40-16.el6.x86_64, openldap-2.4.40-16.el6.i686,
openldap-servers-2.4.40-16.el6.x86_64) [yes I know these are old, but they
*work* -- "If it ain't broke, don't fix it."]. There are two VMs running on
this server, one running Ubuntu 14.04 and the other Ubuntu 18.04. (These two
VMs are/will be servers for DRBL.) The Ubuntu 14.04 VM (and all of its
diskless clients) are perfectly happy to talk to the OpenLDAP server (slapd)
running on the CentOS 6 machine. The Ubuntu 18.04 VM is not. ldapsearch works
everywhere though, so it is NOT the server or the core ldap libraries on any
of the machines (partitularly the Ubuntu 18.04 VM). I can only assume that
there is something fishy with nslcd or the pam/ldap libraries or config on the
Ubuntu 18.04 VM. I have checked everything, but I am coming up empty.  I am 
thinking there might be some "trick" to getting LDAP Authentication to work 
under Ubuntu 18.04 that I am missing.

-- 
Robert Heller             -- 978-544-6933
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