On JNP10K-LC1201, some of heat sinks for ASIC (BT ASIC) may not perform at its maximum cooling capability due to its quality issue discovered over time. This can result in BT ASIC temperature goes higher, showing BT Temp Sensor reaching as high as 115 degrees C and beyond. show chassis environment can look below:

   FPC 0 BT-0 Temp Sensor 1       OK         59 degrees C / 138 degrees F
   FPC 0 BT-0 Temp sensor 0       OK         58 degrees C / 136 degrees F
   FPC 0 BT-1 Temp Sensor 0       OK         119 degrees C / 246 degrees F
   FPC 0 BT-1 Temp Sensor 1       OK         109 degrees C / 228 degrees F
   FPC 0 BT-2 Temp Sensor 0       OK         56 degrees C / 132 degrees F
   FPC 0 BT-2 Temp Sensor 1       OK         58 degrees C / 136 degrees F

    A minor alarm of temperature based performance throttling on BT ASIC can be triggered with the following alarm on a system running 21.4R1-EVO and up:

fpc0-resiliencyd[17668]: CMError: /fpc/0/evo-cda-bt/0/cm/0/btchip/1/btchip_temp_monitor_pfe_throttled_bandwidth (0x452103), scope: pfe, category: functional, severity: minor, module: btchip, type: btchip_temp_monitor_pfe_throttled_bandwidth, oc_category: default

    Higher temperature in a component can trigger the fan speed change, that can lead to an alarm on a monitoring system as well.

NA

    BT ASIC is designed to operate normally and indefinitely with its temperature being as high as 123 degrees C. Juniper recommend to plan for replacement of a JNP10K-LC1201 that has its BT Temp Sensor going up to 115 degrees C. Please contact JTAC for RMA replacement.

    Also, it is encouraged to disable BT ASIC temperature based performance throttling through the CLI knob below, as this throttling feature can be triggered as low as 89 degrees C, that is before BT ASIC temperature reaches to the alarming levels:

set chassis fpc <slot> pfe <pfe-id> temp-perf-throttle-disable

05/07/2026: Initial draft

05/11/2026: FAQ added