IPv6 - ACLs, RAs, and RSes
However, these implicit statements do not include the permitting of Router Advertisements (RAs) and Router Solicitations (RSes), which are important messages needed for the correct operation of IPv6 stateless autoconfiguration, or SLAAC.
In order to permit RAs and RSes, the following statements should be added to the ACL:
permit icmp any any router-advertisement permit icmp any any router-solicitation
It is also important to remember the fact that outgoing ACLs of all types will not filter locally generated traffic.