Hi, I am looking for Cisco IOS command to block specific ICMPv6 message type and code. For example how to block only code 1 (communication with destination administratively prohibited) of message type 1 (destination unreachable). All other code will be permited. deny icmp any any type 1 code 1 In my router I can see these: Router(config-ipv6-acl)#deny icmp any any destination-unreachable ? auth Match on authentication header dest-option Destination Option header (all types) dest-option-type Destination Option header with type dscp Match packets with given dscp value flow-label Flow label log Log matches against this entry log-input Log matches against this entry, including input mobility Mobility header (all types) mobility-type Mobility header with type routing Routing header (all types) routing-type Routing header with type sequence Sequence number for this entry time-range Specify a time-range <cr> My IOS is c2800nm-ipvoicek9-mz.124-24.T2 Regards Rom