Specifications

•
http://hostname/pathname
•
scp://hostname/pathname (available only for Canada and U.S. version)
The validate option validates the software package against the current configuration
as a prerequisite to adding the software package to ensure that the router reboots
successfully. This is the default behavior when the software package being added is
a different release.
Adding the reboot command reboots the router after the upgrade is validated and
installed. When the reboot is complete, the router displays the login prompt. The
loading process can take 5 to 10 minutes.
Rebooting occurs only if the upgrade is successful.
NOTE: After you install a Junos OS Release 13.3 jinstall package, you cannot
issue the requestsystem software rollback command to return to the previously
installed software. Instead you must issue the request system software add
validate command and specify the jinstall package that corresponds to the
previously installed software.
Upgrade and Downgrade Support Policy for Junos OS Releases
Support for upgrades and downgrades that span more than three Junos OS releases at
a time is not provided, except for releases that are designated as Extended End-of-Life
(EEOL) releases. EEOL releases provide direct upgrade and downgrade paths—you can
upgrade directly from one EEOL release to the next EEOL release even though EEOL
releases generally occur in increments beyond three releases.
You can upgrade or downgrade to the EEOL release that occurs directly before or after
the currently installed EEOL release, or to two EEOL releases before or after. For example,
Junos OS Releases 10.0, 10.4, and 11.4 are EEOL releases. You can upgrade from Junos
OS Release 10.0 to Release 10.4 or even from Junos OS Release 10.0 to Release 11.4.
However, you cannot upgrade directly from a non-EEOL release that is more than three
releases ahead or behind. For example, you cannot directly upgrade from Junos OS
Release 10.3 (a non-EEOL release) to Junos OS Release 11.4 or directly downgrade from
Junos OS Release 11.4 to Junos OS Release 10.3.
To upgrade or downgrade from a non-EEOL release to a release more than three releases
before or after, first upgrade to the next EEOL release and then upgrade or downgrade
from that EEOL release to your target release.
For more information on EEOL releases and to review a list of EEOL releases, see
http://www.juniper.net/support/eol/junos.html
Upgrading a Router with Redundant Routing Engines
If the router has two Routing Engines, perform a Junos OS installation on each Routing
Engine separately to avoid disrupting network operation as follows:
159Copyright © 2015, Juniper Networks, Inc.
Migration, Upgrade, and Downgrade Instructions