[j-nsp] QFX5100 red alarm after power-off

[Richard McGovern]

From https://www.juniper.net/documentation/en_US/release-independent/junos/topics/reference/specifications/chassis-qfx5100-status-leds.html

Red Alarm = A major hardware fault has occurred, such as a temperature alarm or power failure, and the switch has halted.

From this it appears NOT having the Management Port active but configured is consider a "major hardware fault" when switch is in 'system halt or power-off' state.  I might very well assume that besides QFX5100 other products, like 5110 and EX4600 and maybe other EX switches, function the same.

For EX4300 its page states, for RED Alarm:

There is a major alarm. A major alarm indicates a critical error condition that requires immediate attention.

Note: When you connect power to the switch, the Alarm (ALM) LED glows red. This behavior is normal. Plugging an active Ethernet cable into the management (MGMT) port on the switch completes the network link and turns off the ALM LED. (See Connecting a Device to a Network for Out-of-Band Management.)

Connecting the switch to a dedicated management console instead of a network does not affect the ALM LED. The LED remains red until the switch is connected to a network.

An easy test for your QFX5100 would be to power it up and disconnect Management Port and see if alarm goes RED, that is, works like EX4300.

My 2 cents worth.

Richard McGovern
Sr Sales Engineer, Juniper Networks 
978-618-3342
 

On 2/14/19, 12:33 PM, "Anderson, Charles R" <cra at wpi.edu> wrote:

    Maybe it lights the red alarm LED so that someone looking knows that it is shutdown/halted, not running normally.
    
    On Thu, Feb 14, 2019 at 04:57:48PM +0000, Giovanni Bellac via juniper-nsp wrote:
    >  
    > Hi,
    > it matters for us, because I want to know the root cause of the red alarm LED when powering it down with an enabled management port.
    > Kind regards
    >     Am Donnerstag, 14. Februar 2019, 13:12:13 MEZ hat Anderson, Charles R <cra at wpi.edu> Folgendes geschrieben:  
    >  
    >  Why does it matter since the switch is halted/powered off anyway?
    > 
    > On Thu, Feb 14, 2019 at 08:31:43AM +0000, Giovanni Bellac via juniper-nsp wrote:
    > >  Hi,
    > > we are issuing the command (request system power-off) when the switch is booted up normally. We are experiencing this on different JunOS versions (14.1, 17.3, 18.1).
    > > From our last email:
    > > Short update:We experiencing the red alarm only when the management port is connected when powering off the QFX5100-48T - weird...When the management port is not connected when powering down the device, there is no red alarm.
    > > Kind regards
    > > 
    > > 
    > >    Am Mittwoch, 13. Februar 2019, 16:22:59 MEZ hat Anderson, Charles R <cra at wpi.edu> Folgendes geschrieben:  
    > >  
    > >  On Wed, Feb 13, 2019 at 11:08:16AM +0000, Giovanni Bellac via juniper-nsp wrote:
    > > > after powering off a QFX5100-48T (request system power-off) the fans are spinning down and the ALARM LED is lightning red. The switch is working and looking as expected without any error messages.
    > > > 
    > > > Is this a normal behavior ? Has someone a spare unit for a short test ?