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This section looks at configuring the ASA for high availability. Because of the nature of the ASA, a single deployment can be also considered a single point of failure. A failure of the ASA would either prevent access to resources that the ASA is protecting or would prevent internal users from accessing an external resource such as the Internet.
Although many smaller organizations take this risk, the ASA does support virtualization and high availability demanded by larger enterprises and provides fault tolerance if a link or device failure of the ASA occurs.