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Cisco ASA Series CLI Configuration Guide
Chapter 1 Configuring Basic Settings
Monitoring DNS Cache
On the ASA, the
no service password-recovery
command prevents you from entering ROMMON mode
with the configuration intact. When you enter ROMMON mode, the ASA prompts you to erase all Flash
file systems.Yyou cannot enter ROMMON mode without first performing this erasure. If you choose not
to erase the Flash file system, the ASA reloads. Because password recovery depends on using ROMMON
mode and maintaining the existing configuration, this erasure prevents you from recovering a password.
However, disabling password recovery prevents unauthorized users from viewing the configuration or
inserting different passwords. In this case, to restore the system to an operating state, load a new image
and a backup configuration file, if available.
The
service password-recovery
command appears in the configuration file for information only. When
you enter the command at the CLI prompt, the setting is saved in NVRAM. The only way to change the
setting is to enter the command at the CLI prompt. Loading a new configuration with a different version
of the command does not change the setting. If you disable password recovery when the ASA is
configured to ignore the startup configuration at startup (in preparation for password recovery), then the
ASA changes the setting to load the startup configuration as usual. If you use failover, and the standby
unit is configured to ignore the startup configuration, then the same change is made to the configuration
register when the
no service password recovery
command replicates to the standby unit.
Monitoring DNS Cache
The ASA provides a local cache of DNS information from external DNS queries that are sent for certain
clientless SSL VPN and certificate commands. Each DNS translation request is first looked for in the
local cache. If the local cache has the information, the resulting IP address is returned. If the local cache
can not resolve the request, a DNS query is sent to the various DNS servers that have been configured.
If an external DNS server resolves the request, the resulting IP address is stored in the local cache with
its corresponding hostname.
To monitor the DNS cache, enter the following command:
Command
Purpose
show dns-hosts
Show the DNS cache, which includes dynamically learned
entries from a DNS server as well as manually entered name
and IP addresses using the
name
command.
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 ...
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