Cisco ASR 5500, Руководство системного администратора

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Context Selection for Subscriber Sessions
The context selection process for a subscriber session is more involved than that for the administrative users.
Subscriber session context selection information for specific products is located in the
Administration Guide
for the individual product.
Understanding Configuration Files
The system supports the use of a file or script to modify configurable parameters. Using a file for offline
system configuration reduces the time it takes to configure parameters on multiple systems.
A system configuration file is an ASCII text file that contains commands and configuration parameters. When
you apply the configuration file, the system parses through the file line-by-line, testing the syntax and executing
the command. If the syntax is incorrect, a message is displayed to the CLI and the system proceeds to the next
command. Lines that begin with # are considered remarks and are ignored.
Pipes ( | ), used with the
grep
and
more
keywords, can potentially cause errors in configuration file
processing. Therefore, the system automatically ignores keywords with pipes during processing.
Important
Always save configuration files in UNIX format. Failure to do so can result in errors that prevent
configuration file processing. Important
The commands and configuration data within the file are organized and formatted just as they would be if
they were being entered at the CLI prompt. For example, if you wanted to create a context called
source in
the CLI, you would enter the following commands at their respective prompts:
[local]
host_name
#
config
[local]
host_name
(config)#
context source
[source]
host_name
(config-ctx)#
end
To create a context called source using a configuration file, you would use a text editor to create a new file
that consists of the following:
config
context source
end
There are several important things to consider when using configuration files:
• The system automatically applies a configuration file at the end of the boot process. After the system
boots up for the first time, a configuration file that you have created and that is tailored to your network
needs, can be applied. To make the system use your configuration file, modify the system's boot
parameters according to the instructions located in
Software Management Operations .
• In addition to being applied during the boot process, you can also apply configuration files manually at
any time by executing the appropriate commands at the CLI prompt. Refer to the instructions in
Software
Management Operations .
ASR 5500 System Administration Guide, StarOS Release 21.5
8
System Operation and Configuration
Context Selection for Subscriber Sessions