Upgrades for SRX Series Firewalls
Learn how to upgrade Junos OS on SRX Series Firewalls with Juniper Networks, covering preparation, software download, verification, execution, and troubleshooting for a smooth transition and minimal downtime.
SRX Series Firewalls are delivered with Junos OS pre-installed on them. When you power on a device, it starts (boots) up using its primary boot device. These devices also support secondary boot devices, allowing you to back up your primary boot device and configuration.
As new features and software fixes become available, you must upgrade Junos OS to use them. Before an upgrade, we recommend that you back up your primary boot device.
Junos OS Upgrades
On SRX Series Firewall, you can configure the primary or secondary boot device with a snapshot of the current configuration, default factory configuration, or rescue configuration. You can also replicate the configuration for use on another device.
If the SRX Series Firewall does not have a secondary boot device configured and the primary boot device becomes corrupted, you can reload the Junos OS package onto the corrupted storage device from a USB flash drive or TFTP server.
Junos OS Upgrade Methods on the SRX Series Firewalls
Certain Junos OS upgrade methods format the device before installation, whereas other methods do not. To install Junos OS Release with the dual-root partitioning scheme, you must use an upgrade method that formats the device before installation.
| Upgrade Methods | Media Formatting Behavior |
|---|---|
| Installation from the boot loader using a TFTP server | Formats device before installation |
| Installation from the boot loader using a USB storage device | Formats device before installation |
| Installation using the J-Web user interface |
|
| Installation using the CLI | Retains existing partitioning scheme |
After you format the device with the dual-root partitioning scheme, you can use conventional CLI or J-Web user interface installation methods for subsequent upgrades.