Junos OS

Expand all | Collapse all

RE Rear Exhaust temperature on MX80

Jump to Best Answer
  • 1.  RE Rear Exhaust temperature on MX80

    Posted 04-17-2020 00:39

    Hi all,

     

    I am junior with Juniper and currently have trouble in finding appropiate information regarding RE Rear exhaust temperature. When I issue show chassis temperature-thresholds command, I get the following output:

    show chassis temperature-thresholds
                               Fan speed      Yellow alarm      Red alarm      Fire Shutdown
                              (degrees C)      (degrees C)     (degrees C)      (degrees C)
    Item                     Normal  High   Normal  Bad fan   Normal  Bad fan     Normal
    Chassis default              48    54       65       55       75       75      100
    Routing Engine               65    70       85       75       95       80      100
    

    and when issue show chassis environment I get this:

     show chassis environment
    Class Item                           Status     Measurement
    Temp  PEM 0                          OK
          PEM 1                          OK
          RE 0 Intake                    OK         52 degrees C / 125 degrees F
          RE 0 Front Exhaust             OK         55 degrees C / 131 degrees F
          RE 0 Rear Exhaust              OK         56 degrees C / 132 degrees F
          Routing Engine                 OK         59 degrees C / 138 degrees F
          Routing Engine CPU             OK         70 degrees C / 158 degrees F
          TFEB 0 QX 0 TSen               OK         60 degrees C / 140 degrees F
          TFEB 0 QX 0 Chip               OK         70 degrees C / 158 degrees F
          TFEB 0 LU 0 TSen               OK         60 degrees C / 140 degrees F
          TFEB 0 LU 0 Chip               OK         71 degrees C / 159 degrees F
          TFEB 0 MQ 0 TSen               OK         60 degrees C / 140 degrees F
          TFEB 0 MQ 0 Chip               OK         66 degrees C / 150 degrees F
          TFEB 0 TBB PFE TSen            OK         62 degrees C / 143 degrees F
          TFEB 0 TBB PFE Chip            OK         80 degrees C / 176 degrees F
    Fans  Fan 1                          OK         Spinning at high speed
          Fan 2                          OK         Spinning at high speed
          Fan 3                          OK         Spinning at high speed
          Fan 4                          OK         Spinning at high speed
          Fan 5                          OK         Spinning at high speed
    

    I cannot find anywhere in documentation how to match  chassis default and/or Routing engine Yellow alarm temperatures with RE 0 Rear Exhaust measurement temperature?

    The thing is that we have monitoring system which often display a warning for RE Rear Exhaust temperature with value 57 degrees Celsius, which is lower than temperature thresholds displayed above, but I am not sure is it OK to put threshold in monitoring system at 65 degrees Celsius or something like that, because I cannot find a connection beetwen these two values.

     

    Any help is greatly appreciated.

     



  • 2.  RE: RE Rear Exhaust temperature on MX80

     
    Posted 04-17-2020 03:04

    Hey domac385,

     

    Greetings, I would not recommend you to change the default values, this is only recommended under really rare circumstances and for that same reason the commands are hidden, I would definitely encourage you to do any necessary adjustments in your monitoring system, please refer to the following thread: https://forums.juniper.net/t5/Ethernet-Switching/changing-temperature-thresholds-on-EX-switch/td-p/292470

     

     

    If this solves your problem, please mark this post as "Accepted Solution" so we can help others too \:)/

     

    Regards,

     

    Lil Dexx
    JNCIE-ENT#863, 3X JNCIP-[SP-ENT-DC], 4X JNCIA [cloud-DevOps-Junos-Design], Champions Ingenius, SSYB

     



  • 3.  RE: RE Rear Exhaust temperature on MX80

    Posted 04-21-2020 04:10

    Hi,

     

    First - thanks for the answer. Second, what is bothering me is that is it OK in monitoring system (not in the MX80 chassis) change the warning threshold value from 57 degress Celsius to e.g. 65 degress Celsius.

    Value I get as RE Rear Exhaus temperature in monitoring system from where this value is read? Is it chassis default yellow alarm temperature form show chassis temperature-threshold or is it some other value that is picking up?



  • 4.  RE: RE Rear Exhaust temperature on MX80

     
    Posted 04-22-2020 02:54

    The values would be read from their specific OID in snmp.  Chassis yellow and red alarms are general aggregate values of just on or off for any chassis related alarm.  Yellow for warning and red for critical.  These simply show the current value of the front panel led off, yellow or red.  It does not give any detail of what alarm is feeding that value.

     



  • 5.  RE: RE Rear Exhaust temperature on MX80

    Posted 05-08-2020 07:53

    I wonder how to corelate temperatures shown in first post after command show chassis temperature-thresholds and after comand show chassis environment - to be specific I'm interested in RE Intake temperature, RE Rear Exhaus temperature and RE Front Exhaust temperature?

    What are the thresholds for these specific values from show chassis environment?

    What are the values for yellow alarm, red alarm for these specific values?

    I need this information to know how much I can raise the temperature-threshold in my NMS.

     



  • 6.  RE: RE Rear Exhaust temperature on MX80

    Posted 05-19-2020 05:15

    Hi,

     

    anyone know the answer?

     

    From show chassis environment command, what are the tresholds for the:

    RE 0 Intake

    RE 0  Front Exhaust

    RE 0 Rear Exhaust?

     

    With this command I read current temperature, but what are the tresholds for warning temperature (yellow alarm) and for critical (red alarm)?

     



  • 7.  RE: RE Rear Exhaust temperature on MX80

    Posted 05-19-2020 05:21

    Hi domac385, 

     

    Command:

    show chassis temperature-thresholds

    root@lab> show chassis temperature-thresholds 
                                            Fan speed      Yellow alarm      Red alarm      Fire Shutdown
                                           (degrees C)      (degrees C)     (degrees C)      (degrees C)
    Item                                  Normal  High   Normal  Bad fan   Normal  Bad fan     Normal
    Chassis default                           48    54       65       55       80       65        100
    Routing Engine 0                          70    80       95       95      110      110        112
    FPC 0                                     55    60       75       65       90       80         95
    FPC 11                                    55    60       75       65       90       80         95
    Top Fan Tray 0                            48    54       77       67       90       75        120
    Bottom Fan Tray 1                         48    54       77       67       90       75        120

     

    Please mark "Accept as solution" if this answers your query. 

    Kudos are appreciated too! 

     

    Regards, 

    Sharat Ainapur



  • 8.  RE: RE Rear Exhaust temperature on MX80

    Posted 05-19-2020 05:24

    Hi domac385,

     

    The following conditions automatically cause the fans to run at full speed and also trigger the indicated alarm:

    • A fan fails (red alarm).

    • The router temperature exceeds the “temperature warm” threshold (yellow alarm).

    • The temperature of the router exceeds the maximum “temperature hot” threshold (red alarm and automatic shutdown of the power supplies).

    To view the temperature threshold settings, issue the show chassis temperature-thresholds command.

                               Fan speed        Yellow alarm         Red alarm
    Item                     Normal   High    Normal   Bad fan    Normal   Bad fan
    Chassis default              48     54        65        55        75        65
    Routing Engine               55     60        75        65        85        70

     

    https://www.juniper.net/documentation/en_US/release-independent/junos/topics/topic-map/mx5-10-40-80-site-prep-reqs.html

     

    https://www.juniper.net/documentation/en_US/junos/topics/reference/command-summary/show-chassis-temperature-thresholds.html

     

    Hope this helps 🙂

     

    Please mark "Accepted Solution" if this works for you.



  • 9.  RE: RE Rear Exhaust temperature on MX80

    Posted 05-19-2020 06:31

    Hi,

     

    thanks for the answers. I am aware of the command show chassis temperature-tresholds, but from my perspective it doesn't apply to all of the above mentioned parameters.

    When I issue show chassis environment command I get (output omitted):

     show chassis environment
    Class Item                           Status     Measurement
    Temp  PEM 0                          OK
          PEM 1                          OK
          RE 0 Intake                    OK         50 degrees C / 122 degrees F
          RE 0 Front Exhaust             OK         53 degrees C / 127 degrees F
          RE 0 Rear Exhaust              OK         54 degrees C / 129 degrees F
    

    As you can see, those are different temperatures for Intake, Front Exhaust and Rear Exhaust. Therefore, it couldn't be the same temperature tresholds for all of the three values. From my perspective, Intake temperature and Exhaust temperature shouldn't be the same because Exhaust temperature takes some of the heat from the chassis. So it isn't the same treshold for Intake temperature and Exhaust temperature. And there we have Rear Exhaust and Front Exhaust which also dont dissipate the same amount of temperature.

     

    So, my question is how to tell which treshold is for which of these values?



  • 10.  RE: RE Rear Exhaust temperature on MX80
    Best Answer

    Posted 05-19-2020 06:54

    Hi domac385,

     

    As per my understanding, the temperature thresholds command output does not aggregate its thresholds for Intake/Exhaust(Front and Back). It displays the threshold ranges those of which, when the RE hits, there will be an alert based on which range the temperature lies in.

     

    I would like to understand it as the temperature maintained on the box and not the temperature of the air flowing in or out of the RE. I believe both the outputs cannot be directly comparable as they serve different purposes. 

     

    I would conclude it this way:

    One(show chassis temperate-thresholds) which gives us the temperature threshold above which the RE is prone to fall under an alert zone. Another( show chassis environment) which gives us the temperature of the Air Flowing in and out of the RE which is more or less regarding the RE environment.

    Unfortunately, there is no command to check the threshold for each Air Flow direction. 

     

    Hope this helps 🙂

     

    Please mark this "Accepted Solution" if this works for you.

    Kudos are very much appreciated.



  • 11.  RE: RE Rear Exhaust temperature on MX80

     
    Posted 05-19-2020 06:05

    Hi domac385,

     

    There is such command to check threshoulds for below items. you can check overall RE temp using "show chassis temperature-thresholds "

     

    RE 0 Intake

    RE 0  Front Exhaust

    RE 0 Rear Exhaust?

     

     

    If this solves your problem, please mark this post as "Accepted Solution" so we can help others too

     

    Kudos are appreciated too 

     

     

    Regards,

    Nadeem

     



  • 12.  RE: RE Rear Exhaust temperature on MX80

     
    Posted 04-19-2020 06:17

    As previously mentioned, these thresholds are set to warning for the reliability of the hardware long term.  Your best solution to this issue is to examine the rack layout of the gear and move the MX or other items around so that the rear area has a cooler position within the specification.

     

    The next best solution if you cannot fix the actual temperature problem is to tune the NMS alert system with the automated ignore or acknowledge levels built into alert monitoring.  This maintains the correct data coming from the MX but stops you getting alarms you are not in a position to fix.