Master RE shows these logs:

Feb 9 19:34:05.126 2024 chassisd[8847]: %DAEMON-5-CHASSISD_SNMP_TRAP10: SNMP trap generated: Fru Offline (jnxFruContentsIndex 9, jnxFruL1Index 2, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName Routing Engine 1, jnxFruType 6, jnxFruSlot 1, jnxFruOfflineReason 2, jnxFruLastPowerOff 0, jnxFruLastPowerOn 0)

Feb 9 19:34:05.804 2024 chassisd[8847]: %DAEMON-5-CHASSISD_SNMP_TRAP7: SNMP trap generated: Fru Online (jnxFruContentsIndex 9, jnxFruL1Index 2, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName Routing Engine 1, jnxFruType 6, jnxFruSlot 1)

Feb 9 19:34:15.217 2024 chassisd[8847]: %DAEMON-5-CHASSISD_SNMP_TRAP10: SNMP trap generated: Fru Offline (jnxFruContentsIndex 9, jnxFruL1Index 2, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName Routing Engine 1, jnxFruType 6, jnxFruSlot 1, jnxFruOfflineReason 2, jnxFruLastPowerOff 0, jnxFruLastPowerOn 0)

Feb 9 19:34:26.056 2024 chassisd[8847]: %DAEMON-5-CHASSISD_SNMP_TRAP7: SNMP trap generated: Fru Online (jnxFruContentsIndex 9, jnxFruL1Index 2, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName Routing Engine 1, jnxFruType 6, jnxFruSlot 1)

RE1 is online:

Routing engine status:

 Slot 0:

  Current state         Master

  Election priority       Master (default)

Start time           2022-12-10 00:33:36 GMT

  Uptime             426 days, 18 hours, 54 minutes, 25 seconds

  Last reboot reason       0x4000:VJUNOS reboot

 Slot 1:

  Current state         Backup

  Election priority       Backup (default)

  Start time           2022-12-10 00:40:53 GMT

  Uptime             426 days, 18 hours, 47 minutes, 3 seconds

  Last reboot reason       0x4000:VJUNOS reboot

There are no alarms

Mastership logs of master RE shows no response from backup:

Feb 9 19:34:15 No response from the other routing engine for the last 2 seconds.

Feb 9 19:34:15 Currentstate master NextState master reason_code 1

Feb 9 19:34:15 new state = master

Feb 9 19:34:15 vc master RE state change: in-synch -> initializing

Feb 9 19:34:15 vc master RE append vc ext disabled

Feb 9 19:34:15 mcontrol_ore_alive_set: other RE is alive

Feb 9 19:34:22 mcontrol_ore_alive_set: other RE is not alive

Feb 9 19:34:22 ORE not alive, keepalive loss 1 above threshold of 0

Feb 9 19:34:26 mcontrol_ore_alive_set: other RE is alive

Feb 9 19:34:26 event = E_ORE_B, state = master, param = 0x0xb7f5008

Feb 9 19:34:26 currentAction = A_NOOP

Feb 9 19:34:26 Currentstate master NextState master reason_code 1

Feb 9 19:34:26 new state = master

Feb 9 19:34:26 vc master RE state change: initializing -> synching

Feb 9 19:34:26 vc master RE append vc ext enabled

Feb 9 19:34:26 vc master RE recv backup RE vc data, mid=255 sn=ÿÿÿÿÿÿÿÿÿÿÿÿ slots=8

Feb 9 19:34:26 vc master RE state change: synching -> in-synch

Feb 9 19:34:51 mcontrol_ore_alive_set: other RE is not alive

Feb 9 19:34:51 ORE not alive, keepalive loss 1 above threshold of 0

Feb 9 19:34:52 mcontrol_ore_alive_set: other RE is alive

RE1 logs shows normal

RE1 is not going offline, but the SNMP traps are being generated

Reboot RE1 to clear the issue, and upgrade to a fixed version to prevent it happening again, this is related to this PR https://prsearch.juniper.net/problemreport/PR1524390