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1-25
Cisco ASA Series CLI Configuration Guide
Chapter 1 Configuring Multiple Context Mode
Changing Between Contexts and the System Execution Space
Automatically Assigning MAC Addresses to Context Interfaces
This section describes how to configure auto-generation of MAC addresses.
The MAC address is used to classify packets within a context. See the
Addresses” section on page 1-11
for more information, especially if you are upgrading from an earlier
ASA version. See also the
“Viewing Assigned MAC Addresses” section on page 1-37
.
Guidelines
•
When you configure a
nameif
command for the interface in a context, the new MAC address is
generated immediately. If you enable this feature after you configure context interfaces, then MAC
addresses are generated for all interfaces immediately after you enable it. If you disable this feature,
the MAC address for each interface reverts to the default MAC address. For example, subinterfaces
of GigabitEthernet 0/1 revert to using the MAC address of GigabitEthernet 0/1.
•
In the rare circumstance that the generated MAC address conflicts with another private MAC
address in your network, you can manually set the MAC address for the interface within the context.
See the
“Configuring the MAC Address and MTU” section on page 1-10
to manually set the MAC
address.
Detailed Steps
Changing Between Contexts and the System Execution
Space
If you log in to the system execution space (or the admin context), you can change between contexts and
perform configuration and monitoring tasks within each context. The running configuration
that you edit
in a configuration mode, or that is used in the
copy
or
write
commands, depends on your location. When
you are in the system execution space, the running configuration consists only of the system
configuration; when you are in a context, the running configuration consists only of that context. For
example, you cannot view all running configurations (system plus all contexts) by entering the
show
running-config
command. Only the current configuration displays.
Command
Purpose
mac-address auto
[
prefix
prefix
]
Example:
hostname(config)# mac-address auto prefix
19
Automatically assigns private MAC addresses to each context interface.
If you do not enter a prefix, then the ASA autogenerates the prefix based
on the last two bytes of the interface (ASA 5500) or backplane (ASASM)
MAC address.
If you manually enter a prefix, then the
prefix
is a decimal value between
0 and 65535. This prefix is converted to a four-digit hexadecimal number,
and used as part of the MAC address. See the
section for more information about how the prefix is
used.
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: ......