On Sat, 30 Mar 2019 16:44:31 -0400 (EDT) Robert Heller <heller(a)deepsoft.com&gt; wrote: > 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. > I have many Bionic systems running nslcd without any problems. I don't think that it is nslcd that is the problem.

When you are debugging you should turn of nscd. It just gets in the way. If it were me I would make sure that stats logging is on on the LDAP server. Then I would watch the LDAP server log as I attemptes a login on the 18.04 system. Bill