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Port Mirroring Instances issue

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  • 1.  Port Mirroring Instances issue

    Posted 08-23-2020 23:30
      |   view attached

    Hi

    I am playing with port-mirroring feature of MX, My configuration without port-mirroring instance works fine and I can capture the packet without any issue. When I used instances on port-mirroring feature, the feature does not work and No packet is mirrored.

    I enclosed my configuration here. With this configuration I want to send some mirrored packet to one Wireshark PC and some other packets to another WireShark PC, The solution is intended to work with both IPv4 and IPv6

    Two questions:

    1- Why does not port-mirroring instance work on my vMX?

    2- How many instances we can configure for port-mirroring

    Attachment(s)

    txt
    Juniper LOGs.txt   4K 1 version


  • 2.  RE: Port Mirroring Instances issue
    Best Answer

     
    Posted 08-24-2020 00:08

    Hi,

     

    People often miss to associate a port-mirroring instance with FPC, at least I don't see these lines in your configuration. Can you please try adding:

    set chassis fpc 0 port-mirror-instance 1
    set chassis fpc 0 port-mirror-instance 2

     

    If I'm not mistaken, up to two port-mirroring instances can be bound to FPC.

     

    Best regards,

    Sergii

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  • 3.  RE: Port Mirroring Instances issue

    Posted 08-24-2020 03:51

    Hi

    Your note solved my issue, regarding Maximum Number of Mirroring, consider this scenario:

    I have 4xMPC10E-C-MRATE and 1xMPC7E-10GE and on Each MPC10 I connected 1x100GE port to another device.

    Now I want to Mirror inbound traffic on each 100GE port to a dedicated 10GE port on MPC7E. This means I will have four Mirroring session. Consider The  amount of RX traffic on each 100GE port is less than 10GE so the traffic volume is not a concern here.

    Each FPC can have two Mirroring Session so It is not possible on MPC7E-10G to have these four SPAN sessions, Right?

    I consider each MPC as a FPC in this scenario...

    Is this right?

    Thank you

    Alireza



  • 4.  RE: Port Mirroring Instances issue

     
    Posted 08-24-2020 09:19

    Hello,

     

    Thank you for accepting my answer as a solution, it will help other community members to find answers faster!

    As for your question, I don't see any straightforward solution for your scenario. It's more common to see one or two traffic analyzers are used, not four. Unless your intention is to use four separate traffic analyzers, perhaps you can configure 4x10GE interfaces as ae interface and mirror traffic from all interfaces to this ae interface (and then parse the traffic on the traffic analyzer side).

     

    Best regards,

    Sergii

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  • 5.  RE: Port Mirroring Instances issue

    Posted 08-24-2020 22:34

    Hi Sergi

    Thank you for the suggestion,

    1)There is an Interesting point in it, Can we use LACP interface as Port-Mirror destination?

    2) When Juniper says Port-Mirror is supported on one particular MPC, what does this mean? Does it mean Port-Mirror destination or Source?

    3) Is term "FPC" equal to "MPC" in this feature?

     

    Thank you



  • 6.  RE: Port Mirroring Instances issue

     
    Posted 08-25-2020 00:17

    Hello Asoltanian,

     


    1)There is an Interesting point in it, Can we use LACP interface as Port-Mirror destination?


    Although I haven't tested this scenario (and may be completely wrong here), I suspect you should be able to use ae interface (configured with or without LACP) as the port-mirroring destination.

     


    2) When Juniper says Port-Mirror is supported on one particular MPC, what does this mean? Does it mean Port-Mirror destination or Source?


    It would've been easier to tell if you'd provided the link you referred to. In context of port-mirroring feature, probably it means support on FPC where port-mirroring action actually takes place. Depending on your scenario and configuration, it may happen on ingress or egress FPC which forward the original packet that will be mirrored.

     


    3) Is term "FPC" equal to "MPC" in this feature?


    Speaking about MX, yes. In the past both DPCs and MPCs were used in MX (and some customers still use DPCs), but nowadays only MPCs are supported and you can use terms FPC and MPC interchangeably.

     

    Best regards,

    Sergii

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