Re: Ouput drops on ex3300/ex4200 after upgrading to 15.1R5.5

There are 12 open PR for 15.1R5.5 with drop conditions listed.

https://prsearch.juniper.net/InfoCenter/index?page=prsearch#qt=drop&bv=15.1R5&sid=ex&dt=0&mode=simpleall&start=0&srtBy=igeneric1&rs=2&nsl=_007!generic2!Open!Y|_006!docdatetime!0!N|_002!junosversion!2!N

I would check to see if your configuration usage would match any of these known issues.  None of them are cosmetic but actual traffic drops.

If you don't seem to match an existing PR, I would open a JTAC ticket and have the issue investigated.