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Welcome to the NOW Way to Wi-Fi

Take your networking performance to new heights with a modern, cloud-native, AI-Native architecture. Only Juniper can help you unleash the full potential of Wi-Fi 7 with our AI-Native platform for innovation.
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Juniper’s AI data center solution is a quick way to deploy high performing AI training and inference networks that are the most flexible to design and easiest to manage with limited IT resources.
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Shaping Student Experiences: The NOW Way to Build Higher Education Networks

Juniper Networks CIO Sharon Mandell and a virtual summit of C-level IT leaders from prestigious institutions discuss ongoing efforts to support digital transformation on campus.
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Security in healthcare

In this IDC Spotlight report, discover how AI networking can automate and strengthen a healthcare ecosystem to defeat criminals and prevent loss. 
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The Future of In-Store Technologies

Retail experts Kevin McCartan, Senior IT Service Delivery Engineer at Musgrave; Jack Stratten of Insider Trends; and Christian Gilby, Senior Director of Product Marketing at Juniper Networks, discuss customer experiences.
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Juniper ACX7020 Cloud Metro Access Router

Legacy networks simply cannot meet the demands of today’s rapidly evolving metro landscape. Unlock a new generation of highly scalable architectures and automated operations with the Juniper ACX7020. 
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EX4000 Ethernet Switch

Next-gen AI-Native EX4000 line of switches

Lack of AI innovation from your current networking vendor slowing you down? Embrace Juniper’s cloud-native, AI-Native access switches that support every level and layer, across nearly every deployment.
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Delivering practical solutions and enriching discussions, this podcast series is a vital resource for those seeking an in-depth exploration of AI's transformative potential.
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Juniper AI Data Center Deployment Services Optimize Your AI Model Runs

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Home Documentation Junos OS Release Notes: Junos OS Release 21.4R1 Junos OS Release Notes for MX Series What's New What's New in 21.4R1

Release Notes: Junos OS Release 21.4R1

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Release Notes: Junos OS Release 21.4R1
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{ "lLangCode": "en", "lName": "English", "lCountryCode": "us", "transcode": "en_US" }
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Software Installation and Upgrade

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  • Migration of Linux kernel version—Starting in Junos OS Release 21.4R1, the following devices support the Wind River LTS19 kernel version:

    Platforms Routing Engine Supported

    ACX5448, ACX5448-D, and ACX5448-M

    RE-ACX-5448

    MX240, MX480, and MX960 RE-S-X6
    MX2020 and MX2010 REMX2K-X8
    MX204 RE-S-1600x8
    MX10003 RE-S-1600x8
    MX2008 REMX2008-X8
    MX10008, and MX10016 RE X10
    PTX1000 RE-PTX1000
    PTX5000 RE-PTX-X8
    PTX10002 RE-PTX10002-60C
    PTX10008 RE-PTX-2X00x4/RE X10
    PTX10016 RE-PTX-2X00x4/RE X10
    QFX10002 RE-QFX10002-60C
    EX9204, EX9208, and EX9214 EX9200-RE2
    EX9251 EX9251-RE
    EX9253 EX9253-RE
    SRX5400, SRX5600, and SRX5800 SRX5K-RE3 (SRX5k RE-2000x6)

    Starting in Junos OS Release 21.4R1, in order to install VM Host image based on Linux WR LTS19, you have to upgrade the i40e NVM firmware to version 7.0 or later.

    [See Upgrading the i40e NVM Firmware on Routing Engines with VM Host Support .]

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