Upgrade and Downgrade Overview

Typically, you upgrade the JUNOS Internet software on a Internet Router by downloading a set of images onto your router or onto another system on your local network, such as a PC. You then uncompress the package and install the uncompressed software using the J-Web interface or the CLI. Finally, you boot your system with this upgraded device.

A JUNOS software package is a collection of files that make up a software component. You can download software packages either for upgrading JUNOS software or for recovering a primary compact flash.

All JUNOS software is delivered in signed packages that contain digital signatures, Secure Hash Algorithm (SHA-1) checksums, and Message Digest 5 (MD5) checksums. For more information about JUNOS software packages, see the JUNOS Installation and Upgrade Guide.

Upgrade Software Packages

Download an upgrade software package, also known as an install package, to install new features and software fixes as they become available.

An upgrade software package name is in the following format: package-name-m.nZx-distribution.tgz.

• package-name is the name of the package—for example, junos-jseries.
• m.n is the software release, with m representing the major release number—for example, 8.0.
• Z indicates the type of software release. For example, R indicates released software, and B indicates beta-level software.
• x represents the version of the major software release—for example, 2.
• distribution indicates the area for which the software package is provided—domestic for the United States and Canada and export for worldwide distribution.

A sample J-series upgrade software package name is junos-jseries-8.0R2-domestic.tgz.

Recovery Software Packages

Download a recovery software package, also known as an install media package, to recover a primary compact flash device.

A recovery software package name is in the following format: package-name-m.nZx-export-cfnnn.gz.

• package-name is the name of the package—for example, junos-jseries.
• m.n is the software release, with m representing the major release number—for example, 8.0.
• Z indicates the type of software release. For example, R indicates released software, and B indicates beta-level software.
• x represents the version of the major software release—for example, 2.
• export indicates that the recovery software package is the exported worldwide software package version.
• cfnnn indicates the size of the target compact flash device in megabytes—for example, cf256.

A sample J-series recovery software package name is junos-jseries-8.0R2-export-cf256.gz.