We have faced an issue on Juniper MX960 that some SFPs (10G Optics) were disabled due to ambient temperature exceeded. This was observed in the syslog messages on MX. However after the physical environment being ok , those SFPs were not coming up. Hence the corresponding 10G links were also down.

As per Juniper Documentation , the optics that have been disabled due to temperature can be reactivated through CLI. (https://www.juniper.net/documentation/en_US/junos/topics/reference/command-summary/request-chassis-optics.html)

request chassis optics fpc-slot fpc-slot-number reactivate

But the above command activate only NON-NEBS compliance optics. In our case optics are NEBS compliance verified by shell interface on MPC.

Can someone please guide how to activate NEBS compiance optics that has been disabled by ambient temperature exceeded.


  • I suppose you did try to put the port admin DOWN, then UP. When putting them UP do you have any message in the log?
    – JFL
    May 11, 2020 at 9:46
  • I'll take a look, though it might take me a couple of days. May 11, 2020 at 12:24
  • @JFL. The interface went down due to ambient temperature of optics exceeded.
    – Nabeel
    May 11, 2020 at 23:14
  • Yes I know that, but still if the interface doesn't come back up when the temperature issue is solved, you can still try to put it down / up administratively then check the log.
    – JFL
    May 12, 2020 at 6:12
  • @JordanHead. I have posted an answer. Please check if it is okay. Thanks.
    – Nabeel
    May 26, 2020 at 11:15

1 Answer 1


The answer is based on my experience of the problem.

So in order to activate NEBS compliance optics that has been disabled by ambient temperature exceeded , we can simply take SFP out of line card's port and then plug it back i.e. we have to re seat the SFP. Once re seated , the interface will come up automatically.

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