This KB article provides concise yet comprehensive insights for customers seeking clarification regarding the latest supported version for SRX 5K models with Routing Engine RE-1800X4.

• The latest release versions supported for platforms running such hardware is 21.4R3.
• To confirm the compatibility of your hardware with the desired software version, navigate to the following site: https://support.juniper.net/support/downloads/
• Differentiate between versions compatible with RE3 hardware and those for RE-1800X4 hardware by referencing their respective descriptions.
  • Versions compatible with RE3 hardware will be labeled with the description "SRX5000 Series VMHost (for RE3)".
  • Versions compatible with RE-1800X4 hardware will be labeled with the description "SRX5000 Series".
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