Ethernet Switching
Ethernet Switching

suddenly junos devices rebooting

‎10-04-2019 06:40 AM

Hi all,

How to troubleshoot to determine what reason causes JUNOS devices(srx and ex) rebooting themself suddenly...There is no power outage...


Ethernet Switching

Re: suddenly junos devices rebooting

‎10-04-2019 07:13 AM



tshoot as follows:


  1. If you have service contract with Juniper to log a ticket with JTAC, please open a case with JTAC against the platform (EX & SRX). JTAC folks will take care of the rest for you to provide an RCA.
  2. If you do NOT have service contract with Juniper, then today is your lucky day, will tell you what to do in the following steps
  3. Archive the /var/log/* from EX & SRX and check for core dump if any
  4. In those var/log/ Check for messages log, chassisd log, masterships log and interactive logs files against the device reboot time stamp.
  5. Look out for any interesting logs.. again at some point/stage, you will need Juniper TAC to help understand those logs to conclude an RCA from vendor standpoint. Or if you can analyze them by yourself to determine the cause.
  6. If a core dump generated (if any), you will need JTAC to decode and help you find RCA.
  7. Check of PEM/PDU failure, chassis alarms etc.. but since two of devices have rebooted (Ex & Srx) i assume, check for RACK PDU short circuit outage.


There many other factors to consider and I hope you have service contract for products you have deployed to log a case with JTAC. In case of no service contract, you can try contacting the juniper customer care them to help you log a courtesy case with JTAC if you can to convence them genuinely.





/Karan Dhanak
Ethernet Switching

Re: suddenly junos devices rebooting

‎10-04-2019 07:43 AM

personnally, I find the command show chassis routing-engine useful for a quick look.  it gives a "last Reboot reason" at the end



show chassis routing-engine
Routing Engine status:
Slot 0:
Current state Master
Temperature 26 degrees C / 78 degrees F
CPU temperature 26 degrees C / 78 degrees F
DRAM 1950 MB
Memory utilization 24 percent
5 sec CPU utilization:
User 10 percent
Background 0 percent
Kernel 11 percent
Interrupt 2 percent
Idle 76 percent
Model RE-EX2300C-12T
Start time 2019-08-29 11:17:26 EDT
Uptime 35 days, 23 hours, 18 minutes, 46 seconds
Last reboot reason Router rebooted after a normal shutdown.
Load averages: 1 minute 5 minute 15 minute
0.62 0.52 0.42


Michel Lapointe, GIRAT
Ethernet Switching

Re: suddenly junos devices rebooting

‎10-04-2019 01:21 PM

Hi Arix,


 These KBs may work on your analysis as well:


The default reason for 'Last reboot reason'


Routing Engine reboot reason codes