Upgrade and Downgrade Overview

Typically, you upgrade the JUNOS software on a Services Router by downloading a software image to your router from another system on your local network. Using the J-Web interface or the CLI to upgrade, the router downloads the software image, decompresses the image, and installs the decompressed software. Finally, you reboot the router, at which time it boots from the upgraded software.

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 Software Installation and Upgrade Guide.

Upgrade Software Packages

An upgrade software package name is in the following format: package-name-m.nZx.y-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 and n representing the minor release number—for example, 9.0.
• Z indicates the type of software release. For example, R indicates released software, and B indicates beta-level software.
• x.y represents the software build number and spin number—for example, 1.1.
• 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-9.0R1-domestic.tgz.

Recovery Software Packages

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

A recovery software package name is in the following format: package-name-m.nZxy-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, 7.5.
• Z indicates the type of software release. For example, R indicates released software, and B indicates beta-level software.
• x.y represents the software build number and spin number—for example, 1.1.
• export indicates that the recovery software package is the exported worldwide software package version.
• cfnnn indicates the size of the target compact flash in megabytes—for example, cf256.

  The following compact flash sizes are supported:

  • 256 MB
  • 512 MB
  • 1024 MB

Compact flash cards with 128 MB storage capacity are not supported.

A sample J-series recovery software package name is junos-jseries-9.0R1-export-cf256.gz.