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Junos OS Release Notes for NFX Series


These release notes accompany Junos OS Release 18.4R2 for the NFX Series. They describe new and changed features, limitations, and known and resolved problems in the hardware and software.

You can also find these release notes on the Juniper Networks Junos OS Documentation webpage, located at

New and Changed Features

This section describes the new features or enhancements to existing features in Junos OS Release 18.4R2 for NFX Series devices.

New and Changed Features: 18.4R2

There are no new features or enhancements to existing features in Junos OS Release 18.4R2 for NFX Series devices.

New and Changed Features: 18.4R1

vSRX Support—Starting in Junos OS Release 18.4R1, vSRX 3.0 is supported on NFX250 devices.

Changes in Behavior and Syntax

This section lists the changes in behavior of Junos OS features and changes in the syntax of Junos OS statements and commands in Junos OS Release 18.4R2 for the NFX Series.

Factory-default Configuration

  • Plug-and-play configuration (NFX150 and NFX250 devices)—The factory default configuration for NFX Series devices is modified to include the secure router plug-and-play configuration.

Known Behavior

This section lists known behavior, system maximums, and limitations in hardware and software in Junos OS Release 18.4R2 for the NFX Series.

For the most complete and latest information about known Junos OS defects, use the Juniper Networks online Junos Problem Report Search application.


  • On NFX150 devices, the TCP and ICMP RPM probes take the best-effort queue of the outgoing interface, instead of the network control queue. As a workaround, configure a DSCP value such as nc1 for the RPM probes to take the network control queue. PR1329643

Platform and Infrastructure

  • The Routing Engine boots from the secondary disk when you:

    • Press the reset button on the RCB front panel, while the RE is booting up before Junos OS reboots.

    • Upgrade the software by booting from the network using the request vmhost reboot network command, and the system fails to boot from the network.

    • Upgrade the BIOS and it fails.

    • Reboot the system and it hangs before Junos OS reboots.

    As a workaround, interrupt the boot process to select the primary disk. PR1344342

  • On NFX250 NextGen devices running Junos OS Release 18.4R1, the memory values of vjunos0, flowd and ovs are as follows:


  • Starting in Junos OS Release 18.4, NFX150 devices support two versions of disk layout. In the older version of the disk layout, you could upgrade or downgrade from Junos OS Release 18.4. With the new disk layout, a downgrade to releases later than Junos OS Release 18.4 is not possible. As a workaround, avoid operations that reformat the disk layout. PR1379983

Known Issues

This section lists the known issues in hardware and software in Junos OS Release 18.4R2 for the NFX Series.

For the most complete and latest information about known Junos OS defects, use the Juniper Networks online Junos Problem Report Search application.


  • On NFX Series devices, if the IRB interface configuration and DHCP service configuration on JDM are removed and rolled back while retaining the VLAN mapping to the IRB interface, the DHCP service fails to assign IP address to the corresponding VNF interfaces and the service chaining fails. As a workaround, remove the VLAN mapping to the IRB interface along with IRB and DHCP service configuration on JDM. PR1234055

  • When you issue a show interface command on NFX150 devices to check the interface details, the system will not check whether the interface name provided is valid or invalid. The system will not generate an error message if the interface name is invalid. PR1306191

  • On NFX150 devices, when you reboot the fpc0 interface, a few error messages are seen in the VTY console. PR1326487

  • On NFX250 devices, libvirt is hung due to which the console access to the device and JDM do not work. PR1341772

  • Starting in Junos OS Release 18.3R1, the reboot time has increased for fpc0 and fpc1 interfaces on NFX150 devices.PR1355527

  • On NFX250 NextGen devices running Junos OS release 18.4, the show vmhost network nfv-back-plane command output shows the Link State/Admin State as down. PR1375908

  • On NFX150 devices, when the interface configuration has the encapsulation flexible-ethernet-services enabled on a 10G interface, traffic gets dropped. PR1425927

Routing Protocols

  • When there is a static route and an OSPF route is active in the routing table for a specific destination network, a ping initiated to that destination network from the NFX device will fail. PR1438443

High Availability

  • On an NFX150 high availability chassis cluster, the host logs updated in the system log messages might not show the correct time stamp. As a workaround, convert the UTC time stamp to local time zone. PR1394778

Platform and Infrastructure

  • Starting in Junos Release 18.1, the file transfer rate from an external media over the network to an NFX150 device is around 40-50 Mbps. PR1290263

  • On NFX150 devices, the request vmhost reboot in minutes command with a delay specified in minutes reboots the device immediately. PR1406018

  • On NFX250 devices, when you issue the request support information command, the configuration and counter data are missing for JDM. PR1413674

Resolved Issues

This section lists the issues fixed in Junos OS 18.4R2 for NFX Series.

For the most complete and latest information about known Junos OS defects, use the Juniper Networks online Junos Problem Report Search application.

Resolved Issues:18.4R2


  • On NFX250 devices, an SFP-T interface does not become active when it is plugged into a ge-12/0/0 or a ge-13/0/0 interface. PR1404756

Platform and Infrastructure

  • JDM depends on the libvirtd deamon to manage the guest VM through cli. The libvirtd daemon was stuck and vjunos VM start up failed, which resulted in in-band connectivity issues, the guest VM could not start, and the console was hung. PR1314945

  • Software upgrade does not delete all images from a previous installation. This occupies about 1GB of storage per upgrade and leads to depletion of storage after several upgrades. PR1408061

  • The NFX3/ACX5448:LIBCOS_COS_TVP_FC_INFO_NOT_FOUND: Forwarding-class information not specified message is displayed when you commit the configuration on config prompt. As a workaround to exclude this from messages or syslogs, run the set system syslog user * match "!(LIBCOS_COS_TVP_FC_INFO_NOT_FOUND: Forwarding-class information not specified) and commit. PR1376665

  • On NFX250 devices, the request-load-configuration command output from device does not match with 18.4 yang. PR1416106

  • With VNF running when MTU is configured, the KVM crashes and VNF goes down. PR1417103

Resolved Issues:18.4R1

There are no fixed issues in Junos OS Release 18.4R1 for NFX Series.

Documentation Updates

There are no errata or changes in Junos OS Release 18.4R2 documentation for NFX Series.

Migration, Upgrade, and Downgrade Instructions

This section contains the procedure to upgrade Junos OS, and the upgrade and downgrade policies for Junos OS for the NFX Series. Upgrading or downgrading Junos OS might take several hours, depending on the size and configuration of the network.

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.

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

Basic Procedure for Upgrading to Release 18.4

When upgrading or downgrading Junos OS, use the jinstall package. For information about the contents of the jinstall package and details of the installation process, see the Installation and Upgrade Guide. Use other packages, such as the jbundle package, only when so instructed by a Juniper Networks support representative.


The installation process rebuilds the file system and completely reinstalls Junos OS. Configuration information from the previous software installation is retained, but the contents of log files might be erased. Stored files on the device, such as configuration templates and shell scripts (the only exceptions are the juniper.conf and ssh files), might be removed. To preserve the stored files, copy them to another system before upgrading or downgrading the device. For more information, see the Junos OS Administration Library.


We recommend that you upgrade all software packages out of band using the console because in-band connections are lost during the upgrade process.

To download and install Junos OS Release 18.4R2:

  1. Using a Web browser, navigate to the All Junos Platforms software download URL on the Juniper Networks webpage:

  2. Select the name of the Junos OS platform for the software that you want to download.
  3. Select the Software tab.
  4. Select the release number (the number of the software version that you want to download) from the Version drop-down list to the right of the Download Software page.
  5. In the Install Package section of the Software tab, select the software package for the release.
  6. Log in to the Juniper Networks authentication system by using the username (generally your e-mail address) and password supplied by Juniper Networks representatives.
  7. Review and accept the End User License Agreement.
  8. Download the software to a local host.
  9. Copy the software to the device or to your internal software distribution site.
  10. Install the new package on the device.

Product Compatibility

Hardware Compatibility

To obtain information about the components that are supported on the devices, and special compatibility guidelines with the release, see the Hardware Guide and the Interface Module Reference for the product.

To determine the features supported on NFX Series devices in this release, use the Juniper Networks Feature Explorer, a Web-based application that helps you explore and compare Junos OS feature information to find the right software release and hardware platform for your network. Find Feature Explorer at:

Hardware Compatibility Tool

For a hardware compatibility matrix for optical interfaces and transceivers supported across all platforms, see the Hardware Compatibility Tool.

Software Version Compatibility

This section lists the vSRX and Cloud CPE Solution software releases that are compatible with the Junos OS releases on the NFX series platforms.


Starting in Junos OS Release 18.1R1, NFX150 and NFX250 devices support the same version of platform software and vSRX. For example, see Table 3.

NFX250 Software Version Compatibility

This section lists the vSRX and CloudCPE Solution software releases that are compatible with the Junos OS releases on the NFX250 platform:

Table 3: Software Compatibility Details with vSRX and Cloud CPE Solution

NFX250 Junos OS Release


Cloud CPE Solution



Cloud CPE Solution 2.0



Cloud CPE Solution 2.1



Cloud CPE Solution 3.0



Cloud CPE Solution 3.0.1



Cloud CPE Solution 4.0



Cloud CPE Solution 4.1



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable



Not applicable