Install, Upgrade, and Downgrade Software
SUMMARY Devices are delivered with Junos OS Evolved already installed on them. As new features and software fixes become available, you must upgrade Junos OS Evolved to use them. You can install software on devices that have either single or redundant routing engines. Before you install a software release on a device, you should make any necessary changes to the configuration and back up the current system.
Junos OS Evolved ensures that all Routing Engines (REs) and FPCs in the system are
running the same software version. When you issue the request system software
add image-name
operational mode command on the primary
RE, the system installs the new version of software on both REs. Once you reboot the
system after a software package installation, all the REs and FPCs in the system run the
new version of the software.
Junos OS Evolved supports storing multiple versions of software on the storage media. You
can view the installed versions on the device with the show system software
list
operational mode command. Each version of the software is stored in a
distinct area in the /soft directory, ensuring that a software
package installation does not impact the other software versions installed in the
system. We recommend you keep no more than 5 versions of software in the system.
In Junos OS, you must first upgrade the software on the standby RE and then switch control to the standby RE to run the new software version. After you are sure the software upgrade on the original standby RE is successful, you can upgrade the original primary RE to the new software version and switch control back to the original primary RE. However, with Junos OS Evolved, you do not need to upgrade the standby RE first. You upgrade both REs using a single command issued on the primary RE.
During a successful installation, the installation package completely re-installs the existing software. It retains configuration files and similar information, such as secure shell and host keys, from the previous version. The previous software package is preserved in a separate disk partition, and you can manually roll back to it if necessary. If the software installation fails for any reason, such as loss of power during the installation process, the system returns to the originally active installation when you reboot. For more background information on software installation, see Software Installation and Upgrade Overview (Junos OS Evolved).
Junos OS Evolved allows you to roll back to any of the releases stored in the system with
the request system software rollback image-name
operational mode command. The system also stores with each release the last
configuration that was running when the release was running. Junos OS Evolved supports
rolling back to an alternate image with the currently-running configuration or with the
saved configuration that corresponds to the rollback software image, with the
request system software rollback with-old-snapshot-config
operational mode command.
If the system does not function properly after the upgrade and reboot, the previous version can be restored by rolling back to the previous version. See the roll back step in the Recover from a Failed Installation Attempt If the CLI Is Working procedure.
For dual-RE devices, if an RE inserted into the device has a different software version,
the new RE is kept out of the system. We recommend that you configure the software to
synchronize automatically to the new RE, by configuring the auto-sw-sync
enable
statement at the [edit system]
hierarchy level.
When this configuration is present, the RE that is in the system copies over all the
images to the new RE and reboots the new RE so that it automatically comes up with the
correct software. You can also choose to synchronize the software to the new RE manually
each time you have to replace an RE, by using the request system software sync
all-versions
operational mode command, which synchronizes the software
versions and configurations. For more information about replacing REs, see Replace a Routing Engine in a Dual-RE System.
Prepare to Install Software
Follow these steps to prepare to install your Junos OS Evolved software:
Prepare both Routing Engines to Join the System
For dual-RE devices, both REs must be participating in the system to be able to
install software on both REs. You must verify that both REs are in the system
and which software versions are currently running in the system. You use the
show system software list
, show system
nodes
, and show system alarms
operational mode
commands to do so and to determine what course of action to take if one of the
REs is not participating in the system.
Issue the show system software list
and show system
nodes
commands on the primary RE to check the status of the REs. If
information about both re0
and re1
appear in
the output, and show a status of Status : online, apps-ready
in
the output of the show system nodes
command, both REs are
operational, part of the system, and are running the same software version. You
can proceed to install the software. See Install the Software Package on a Device with Redundant Routing Engines. For example:
user@host-re0> show system software list [...output truncated...] ------------------------------- node: re0 ------------------------------- Active boot device is primary: /dev/sda List of installed version(s) : '-' running version '>' next boot version after upgrade/downgrade '<' rollback boot version - junos-evo-install-ptx-x86-64-20.4R2.13-EVO - [2021-05-05 09:19:16] < junos-evo-install-ptx-x86-64-20.4R2.14-EVO - [2021-05-05 09:03:23] ------------------------------- node: re1 ------------------------------- Active boot device is primary: /dev/sda List of installed version(s) : '-' running version '>' next boot version after upgrade/downgrade '<' rollback boot version - junos-evo-install-ptx-x86-64-20.4R2.13-EVO - [2021-05-05 09:22:09] < junos-evo-install-ptx-x86-64-20.4R2.14-EVO - [2021-05-05 09:06:50] user@host-re0> show system nodes Node: fpc0 Node Id : 2201170739216 Node Nonce : 2632845278 Status : online, apps-ready Attributes : ASICS (Active), BT (Active), FABRIC_PFE (Active), FPC (Active), PIC (Active), TIMINGD_FPC (Active), MSVCSD (Active) Node: re0 Node Id : 2201170739204 Node Nonce : 1829978227 Status : online, apps-ready Attributes : FABRIC_CONTROL (Active), FABRIC_FCHIP_PARALLEL (Active), RE (Active), TIMINGD_RE (Active), MasterRE (Active), GlobalIPOwner (Active) Node: re1 Node Id : 2201170739205 Node Nonce : 3166228206 Status : online, apps-ready Attributes : FABRIC_CONTROL (Spare), FABRIC_FCHIP_PARALLEL (Spare), RE (Spare), TIMINGD_RE (Spare), BackupRE (Active)
If both REs are present, but the status of one RE is not Status : online,
apps-ready
, you need to take action to bring that RE into the
system. In these examples, re0
is the RE in the system and
re1
is the other RE that needs to join the system:
Install the Software Package on a Device with Redundant Routing Engines
Unlike Junos OS, Junos OS Evolved ensures all nodes in a system are running the same software version. In Junos OS Evolved, the device can contain multiple releases of the software simultaneously if enough space exists. If the device does not have enough space, you must delete an older image of the software before installing a new one. We recommend that you store no more than 5 versions of software on the device.
Before you install a new software release on a device, you should back up the current system. See Back up and Recover Software with Snapshots.
Before you upgrade the software, you must prepare for the installation. See Prepare to Install Software.
The request system software add
operational mode command
installs the software on both the Routing Engines (REs). This command does not
modify the currently running software stack. This command validates the current
configuration using the new version of the software. Once validation succeeds,
the install process checks for sufficient storage on both REs. Once the storage
checks pass, the new software is installed on both REs. You need to reboot the
system to run the new software. The software installation process only affects
traffic for a short while; for more information, see Table 1.
Tasks | Actions | Traffic Impact |
---|---|---|
Add the software | Validate the configuration, check for sufficient storage, install on both REs | None |
Verify the software installation | Show image that will be the current image after the system reboots | None |
Reboot the system | Reboot all REs and FPCs at the same time | Impacted; resumes after the system reboots |
Verify which software image is running | Show image running after reboot | None |
To upgrade the software on a device:
Install the Software Package on a Device with a Single Routing Engine
Before you install a new software release on a device, you should back up the current system. See Back up and Recover Software with Snapshots.
In Junos OS Evolved, the device can contain multiple releases of the software simultaneously as long as the system has enough space. If the system does not have enough space, you must delete an older image of the software before installing a new one. We recommend that you store no more than 5 versions of software on the device.
Before you upgrade the software, you must prepare for the installation. See Prepare to Install Software.
To upgrade the software on a device:
See Also
Recover from a Failed Installation Attempt If the CLI Is Working
If a Junos OS Evolved installation fails, and the CLI is working, use one of these procedures to install Junos OS Evolved, depending upon the situation:
Replace a Routing Engine in a Dual-RE System
Junos OS Evolved ensures all nodes in a system are running the same software version.
If you insert an RE that has the same current software version as the primary RE
into the system, the new RE joins the system, and the configurations and the
other software versions automatically synchronize from the existing RE to the
new RE, even if you have not configured the auto-sw-sync
statement.
If you insert an RE that has a different software version into the system and you
have not configured the auto-sw-sync enable
statement, the RE
is kept outside the system and the system generates a software mismatch alarm.
The alarm message displays the RE name and the version of software on the
newly-inserted RE, similar to the following: Software Version Mismatch
on re1:junos-evo-install-ptx-x86-64-20.4R2.6-EVO.
.
user@host-re0> show system alarms 2 alarms currently active Alarm time Class Description 2021-04-19 16:02:26 PDT Major Re1 Node unreachable 2021-04-19 16:04:46 PDT Major Software Version Mismatch on re1:junos-evo-install-ptx-x86-64-20.4R2.6-EVO
To clear the alarms and bring the RE into the system, manually synchronize the
primary RE to the new RE with the request system software sync
all-versions
operational mode command.
We recommend that you configure the auto-sw-sync enable
configuration statement at the [edit system]
hierarchy level
before inserting a new RE into the system. When you do so, the RE in the system
detects the newly-inserted RE and automatically synchronizes the software to the
new RE. All images are synchronized to the new RE and the system reboots the
newly-inserted RE. When the newly-inserted RE comes back up, it joins the
system. Each software image has the configuration used when the image ran stored
with it. The configuration associated with the current running image is
synchronized from the primary RE to the backup RE. Configurations stored with
the rollback and other images are also synchronized to the backup RE when you
configure the auto-sw-sync enable
statement on the primary
RE.
To replace an RE in a dual-RE system:
Not Enough Disk Space for Software Installation
The software installation process requires a certain amount of unused disk space. If the system does not have enough space, you receive an error message similar to the following:
WARNING: The /soft filesystem is low on free disk space.
WARNING: This package requires 1075136k free, but there is only 666502k
available.
If you need to create enough disk space for the software installation to be successful, you can do the following:
-
Identify and delete older images by using the
show system software list
andrequest system software delete
operational mode commands. -
Identify and delete unnecessary files by using the
show system storage
andrequest system storage cleanup
operational mode commands.
For more information on how to create enough disk space for a software installation, see Ensure Sufficient Disk Space for Upgrades.