> # The any Keyword in Crypto IPv4-ACLs

> Tip We recommend that you configure mirror image crypto IPv4-ACLs for use by IPsec and that you avoid using the any option.

> The any keyword in a permit statement is discouraged when you have multicast traffic flowing through the IPsec interface. This configuration can cause multicast traffic to fail.

> The permit any statement causes all outbound traffic to be protected (and all protected traffic sent to the peer specified in the corresponding crypto map entry) and requires protection for all inbound traffic. Then, all inbound packets that lack IPsec protection are silently dropped, including packets for routing protocols, NTP, echo, echo response, and so forth.

> You need to be sure you define which packets to protect. If you must use any in a permit statement, you must preface that statement with a series of deny statements to filter out any traffic (that would otherwise fall within that permit statement) that you do not want to be protected.

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