"Authentication failure" on Ubuntu 18.04...

[Robert Heller]

At Sat, 30 Mar 2019 15:24:34 -0700 Billy MacAllister <bill at ca-zephyr.org> wrote:

> 
> On Sat, 30 Mar 2019 16:44:31 -0400 (EDT)
> Robert Heller <heller at deepsoft.com> 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.

I am wondering if the problem is the version of 
/lib/x86_64-linux-gnu/security/pam_ldap.so
I have installed.  There appears to be *two* versions available:

One from the package libpam-ldapd and one from the package libpam-ldap.

YES!  I just installed libpam-ldapd (replacing the previously installed 
libpam-ldap), and now things are working!

> 
> 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
> 
>  
> 

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