0,1 and 2 are the SNMP interface IDs, the LAN ports on an MX75 also started at 0 last time I looked, so 4 is 0, 5 is 1 etc.
This why the MX LAN interface page was pulled after less than a week, due to the interface numbering not being consistent. That was a few years ago and it still hasn't come back, so I think the change may be more involved than we think.
I'd love it to be fixed and the LAN interface page to return 🤞🙏
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