What do each of the numbers in 'Junos OS Release 10.4R2' represent?
Understanding how Junos release numbering works and what each section means.
Juniper frequently ships new major versions of the Junos OS to deliver new features and functionality to its customers. Juniper posts new version releases on its software download page: http://www.juniper.net/support/products/
Following the availability of any major version Juniper also issues maintenance and service releases for fixes needed in a release version after its initial shipment. These releases are available to any device with a support contract.
• Maintenance Releases – standard releases provided to support customers for all platforms running the Junos OS to provide fixes in shipped version releases. The software download page links to whatever is the latest revision available.
• Service Releases – targeted releases to provide more timely delivery of critical fixes to meet customer needs. Service releases may be limited to specific platforms or use cases. The service releases are available through JTAC.
Starting in 2010 Junos releases are numbered according to a year.sequence convention. As examples─ the last release of 2010 is 10.4 and the first release in 2011 will be 11.1.
You can determine the release version from the release package name. For example:
• jinstall-ex-4200: descriptor of the release platform, in this example the ex-4200
• 10.4 is the major version number (the 4th release of the year in 2010)
• R is the type of release, in this example the R designates a shipped release (other types are S for service release and B for a Beta release)
• 2 is the revision number, i.e. the numbered sequence of the maintenance releases, where the First Release Shipment (FRS) is always R1
• 6 is the build number (also known as the spin number) of the release. The spin number indicates the specific build of the release and may be requested by JTAC during service discussions.
• Domestic-signed indicates that the software is for use in the US and Canada. The other type is worldwide designated by export-signed.
Service Releases are indicated by an 'S' such as Junos 10.0S10.1.