1-29
Cisco ASA Series CLI Configuration Guide
Chapter 1 Information About NAT
DNS and NAT
and translates the address inside the DNS reply to 10.1.3.14. If you do not enable DNS reply
modification, then the inside host attempts to send traffic to 209.165.201.10 instead of accessing
ftp.cisco.com directly.
Figure 1-22
DNS Reply Modification, DNS Server on Outside
shows a user on the inside network requesting the IP address for ftp.cisco.com, which is on
the DMZ network, from an outside DNS server. The DNS server replies with the mapped address
(209.165.201.10) according to the static rule between outside and DMZ even though the user is not on
the DMZ network. The ASA translates the address inside the DNS reply to 10.1.3.14. If the user needs
to access ftp.cisco.com using the real address, then no further configuration is required. If there is also
DNS Server
Outside
Inside
User
130021
1
2
3
4
5
DNS Reply Modification
209.165.201.10
10.1.3.14
DNS Reply
209.165.201.10
DNS Reply
10.1.3.14
DNS Query
ftp.cisco.com?
FTP Request
10.1.3.14
Security
Appliance
ftp.cisco.com
10.1.3.14
Static Translation
on Outside to:
209.165.201.10
Summary of Contents for 5505 - ASA Firewall Edition Bundle
Page 28: ...Glossary GL 24 Cisco ASA Series CLI Configuration Guide ...
Page 61: ...P A R T 1 Getting Started with the ASA ...
Page 62: ......
Page 219: ...P A R T 2 Configuring High Availability and Scalability ...
Page 220: ......
Page 403: ...P A R T 2 Configuring Interfaces ...
Page 404: ......
Page 499: ...P A R T 2 Configuring Basic Settings ...
Page 500: ......
Page 533: ...P A R T 2 Configuring Objects and Access Lists ...
Page 534: ......
Page 601: ...P A R T 2 Configuring IP Routing ...
Page 602: ......
Page 745: ...P A R T 2 Configuring Network Address Translation ...
Page 746: ......
Page 845: ...P A R T 2 Configuring AAA Servers and the Local Database ...
Page 846: ......
Page 981: ...P A R T 2 Configuring Access Control ...
Page 982: ......
Page 1061: ...P A R T 2 Configuring Service Policies Using the Modular Policy Framework ...
Page 1062: ......
Page 1093: ...P A R T 2 Configuring Application Inspection ...
Page 1094: ......
Page 1191: ...P A R T 2 Configuring Unified Communications ...
Page 1192: ......
Page 1333: ...P A R T 2 Configuring Connection Settings and QoS ...
Page 1334: ......
Page 1379: ...P A R T 2 Configuring Advanced Network Protection ...
Page 1380: ......
Page 1475: ...P A R T 2 Configuring Modules ...
Page 1476: ......
Page 1549: ...P A R T 2 Configuring VPN ...
Page 1550: ......
Page 1965: ...P A R T 2 Configuring Logging SNMP and Smart Call Home ...
Page 1966: ......
Page 2059: ...P A R T 2 System Administration ...
Page 2060: ......
Page 2098: ...1 8 Cisco ASA Series CLI Configuration Guide Chapter 1 Troubleshooting Viewing the Coredump ...
Page 2099: ...P A R T 2 Reference ...
Page 2100: ......