backup

# systemctl stop slapd
slapcat > ldap.ldif
slapcat -b cn=config > ldap-config.ldif

restore

systemctl stop slapd
mv /etc/ldap/slapd.d{,.bak}
mv /var/lib/ldap{,.bak}
mkdir /etc/ldap/slapd.d
mkdir /var/lib/ldap
slapadd -n0 -F /etc/ldap/slapd.d -l ldap-config.ldif
slapadd -l ldap.ldif
chown openldap:openldap -R /etc/ldap/slapd.d
chown openldap:openldap -R /var/lib/ldap
systemctl start slapd