On 2021-02-05 18:55, Uwe Sauter wrote:
# slaptest
601d92d6 /etc/openldap/acl.conf: line 84: unknown attr "pwdHistory" in to clause
[…]
slaptest: bad configuration file!


This is on CentOS with openldap-servers-2.4.44-22.el7.

I'm using 2.4.50 (my own build) on CentOS 7 and I have ACLs on this and other ppolicy attributes without any problems.

You obviously have the ppolicy schema included, but is the ppolicy overlay actually loaded?