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New and Changed Features


This section describes the new features and enhancements in this release.

  • Class of Service support for eight queues—Two-level hierarchical scheduling (per-unit scheduler or hierarchical scheduler) with VLAN queuing is supported for eight queues. Each VLAN uses three traffic classes and eight queues. There are two high-priority queues (Queue 0 and Queue 6), two medium-priority queues (Queue 1 and Queue 7), and four low-priority queues (Queue 2 through Queue 5). Shaping is supported at the traffic class level, not at the queue level. Weighted random early detection, drop profiles, and queue buffer size configuration are not supported. You enable CoS by configuring the flexible-queuing-mode option at the [edit chassis fpc 0] hierarchy level.

  • ESXi hypervisor support—VMware ESXi 5.5 supports SR-IOV as physical PCI device. You can install vMX using an OVA image.

  • Licenses—Evaluation licenses are perpetual. You can download the vMX software and use the BASE application package with 1 Mbps bandwidth without a license indefinitely. In previous releases, you had only 30 days to evaluate the software without a valid license.

    If you upgrade from a BASE package license to an ADVANCE or PREMIUM package license or if you downgrade from an ADVANCE or PREMIUM package license to a BASE package license, you must restart the routing protocol process. If your configuration has logical systems, you must restart the routing protocol process for all logical systems.

  • Performance mode is default for chassis—Performance mode is enabled by default for the chassis. Performance mode needs more vCPUs and memory to run at higher bandwidth, while lite mode needs fewer vCPUs and memory to run at lower bandwidth. Make sure you have configured the proper number of vCPUs and memory for your VMs. We recommend you enable hyperthreading in BIOS.

    To tune performance mode for unicast traffic, you can change the number of Workers dedicated to processing multicast and control traffic. The default specifies that all available Workers are used to process all traffic. You specify the number of dedicated Workers by configuring the number-of-ucode-workers number-workers option at the [edit chassis fpc 0 performance-mode] hierarchy level.

  • Support for 96 ports using lite mode—You can use up to 96 ports for virtio running in lite mode. Other configurations running in performance mode support up to 23 ports.

  • Support for FreeBSD 10 kernel for Junos OS—FreeBSD 10 is the underlying OS for Junos OS instead of FreeBSD 6.1 for vMX. With FreeBSD 10, you can allocate multiple vCPUs to the VCP.

  • Support for X710 NICs—You can use Intel X710 PCI-Express NICs. Before you install vMX, make sure you have updated the drivers.

  • Virtual broadband network gateway—Using vMX, you can deploy a virtual broadband network gateway (vBNG) on x86 servers to terminate broadband subscribers. vBNG supports most of the subscriber management features available with Junos OS Release 16.2 on MX Series routers.

    vBNG runs on vMX, so it has similar exceptions; the following subscriber management features available on MX Series routers are not supported for vBNG:

    • High availability features such as hot-standby backup for enhanced subscriber management and MX Series Virtual Chassis.

    • CoS features such as shaping applied to an agent circuit identifier (ACI) interface set and its members.

    To deploy a vBNG instance, you must purchase these licenses:

    • vMX PREMIUM application package license with 1 Gbps, 5 Gbps, 10 Gbps, or 40 Gbps bandwidth

    • vBNG subscriber scale license with 1000, 10 thousand, 100 thousand, or 1 million subscriber sessions for one of these tiers:




      L2TP features including L2TP LNS services, secure policy, service activation and deactivation


      Features in the Introductory tier, and DHCP subscriber services, PPP/LAC subscriber services, DHCP relay and DHCP local server


      Features in the Preferred tier, and pseudowire ingress termination

      With the appropriate vMX PREMIUM license, you can evaluate vBNG without a vBNG subscriber scale license for 30 days. After 30 days, you are limited to 10 subscriber sessions.

    [See Junos OS Broadband Subscriber Management and Services Library.]