4.16 Understanding How and Where the Configuration Files Are Stored

The Juniper Networks router offers a very robust mechanism for managing your configuration files. JUNOS is based on FreeBSD UNIX, so there are a lot of powerful UNIX features available in the CLI. In this section, we discuss how to manage your configuration files.

When you enter the configuration mode, JUNOS copies the current configuration to a file called the candidate configuration. This candidate configuration allows you and other users to see changes that have been made to the configuration. However, any changes made will not take effect until they have been committed. In other words, if you enter the configuration mode and change the system name to mynewsystem , that new name is visible in the candidate configuration file. However, the prompt still displays the current name. When you commit the configuration changes by typing the commit command, you will then see the new system name for the router.

JUNOS works with the active configuration file, candidate configuration file, and the previous nine committed configuration files. These files are stored in different locations within the Juniper Networks router. The active configuration file is named juniper.conf and is stored in the /config directory on the flash memory. In addition to the juniper.conf file, there are three more files stored in /config : juniper.conf.1.gz , juniper.conf.2.gz , and juniper.conf.3.gz . These three files are zipped files, but the active configuration file is not. The remaining five configuration files are stored on the hard disk in the /var/db/config directory and follow the same naming convention as the others, starting with number four.

The following example shows the operational-mode syntax to display a listing of the files. It also shows an example of how to display their content in the CLI.

 lab@Chicago> file list ?  Possible completions:   <[Enter]>            Execute this command   <path>               Path to list lab@Chicago> file list /config juniper.conf juniper.conf.1.gz juniper.conf.2.gz juniper.conf.3.gz lab@Chicago> file list /var/db/config/ juniper.conf++ juniper.conf.4.gz juniper.conf.5.gz juniper.conf.6.gz juniper.conf.7.gz juniper.conf.8.gz juniper.conf.9.gz juniper.conf.post-install juniper.conf.pre-install lab@Chicago> file show ? Possible completions:   <filename>           Filename to display lab@Chicago> file show /config/juniper.conf version 5.1R1.4; system {     host-name Chicago;