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  • 1.  QFX5120 out of band managment interfaces em0 / em1

    Posted 06-15-2021 05:04
    The QFX5120 appears to have two management interfaces - em0 & em1. I seem to be struggling to find much documentation on em1 and how it can be used. Can anyone tell me how em1 can be used?
    Is it possible to use a single IP address switched through both ports similar to a vme interface on a VC/VCF?
    Are you supposed to configure separate IP addresses on them and use 'qualified-next-hop'?

    Any help with this is much appreciated.

    JNCIE-ENT #552

  • 2.  RE: QFX5120 out of band managment interfaces em0 / em1

    Posted 06-25-2021 16:54
    Hi Regalis,

    We use them with a "secondary" IP-Address to use if the primary OOB-Network suffers from an outage.
    The IP is not shared like a vme - it's just another layer of redundancy if you use both of them (at least that's how we use them).
    You don't have to use both of them (most customers only use em0), but if you have an OOB and a secondary OOB, this is very helpful :)

    I hope this helps a bit - but indeed, the Docs are very slim - I will reach out to the folks responsible for making it more clear in the Docs :)


    Christian Scholz
    Juniper Networks Ambassador | JNCIE-SEC #374
    Blog: | Twitter: @chsjuniper | YT-Channel: netchron

  • 3.  RE: QFX5120 out of band managment interfaces em0 / em1

    Posted 08-16-2021 17:36
    a. The only difference between em0 and em1, is that em1 only allows for SFP media type, and em0 allows for both cooper and fiber. You can use it at your convenience depending on the type of cabling you have in your out-of-band network.
    b. These two interfaces are different, so separate IP's are expected.