Cisco Systems ASA 5580 Manual De Usuario

This section includes the following topics:

To configure the Botnet Traffic Filter, perform the following steps:

Enable use of the dynamic database. See the 

. 

This procedure enables database updates from the Cisco update server, and also enables use of the 
downloaded dynamic database by the ASA. Disallowing use of the downloaded database is useful in 
multiple context mode so you can configure use of the database on a per-context basis.

(Optional) Add static entries to the database. See the 

. 

This procedure lets you augment the dynamic database with domain names or IP addresses that you want 
to blacklist or whitelist. You might want to use the static database instead of the dynamic database if you 
do not want to download the dynamic database over the Internet.

Enable DNS snooping. See the 

. 

This procedure enables inspection of DNS packets, compares the domain name with those in the 
dynamic database or the static database (when a DNS server for the ASA is unavailable), and adds the 
name and IP address to the DNS reverse lookup cache. This cache is then used by the Botnet Traffic 
Filter when connections are made to the suspicious address.

Enable traffic classification and actions for the Botnet Traffic Filter. See the 

. 

This procedure enables the Botnet Traffic Filter, which compares the source and destination IP address 
in each initial connection packet to the IP addresses in the dynamic database, static database, DNS 
reverse lookup cache, and DNS host cache, and sends a syslog message or drops any matching traffic.

(Optional) Block traffic manually based on syslog message information. See the 

.

If you choose not to block malware traffic automatically, you can block traffic manually by configuring 
an access rule to deny traffic, or by using the shun command to block all traffic to and from a host.