Hi,
Please go throug the following link for configuring port mirroring :-
https://kb.juniper.net/InfoCenter/index?page=content&id=KB21842&actp=search
Please take note of the Limitation #8 :-
Port mirroring works only if the mirrored and the mirroring ports are on the same FPC and PIC.
Example: It works for ports xe-7/0/0 and 7/0/1. However, it will not work for ports xe-8/0/0 and xe-8/1/0, as the PICs are different.
Regards,
Sahil Sharma
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