Alias_and and alias_or alias options
alias_or alias options control whether subsequent access control clauses (e.g.,
alias_auth_mapping, etc.) are ANDed or ORed. They are analogues of the legacy configuration alias file named parameters [AND] and [OR], respectively. The default is controlled by the
or_clauses MTA option---and is AND (for backwards compatibility) by default.
For groups and lists defined in LDAP, see also the
OR values for the
mgrpBroadcasterPolicy attribute (or more precisely, the attribute named by the
ldap_auth_policy MTA option). For a more detailed discussion, see Mailing list multiple access control interpretation.