[j-nsp] MX204 and QSFP+ breakouts

[Ross Halliday]

Dear list,

On a lark we picked up 4x10GbE breakouts for our MX204. Currently we've tried a couple different versions, a plain ol' passive DAC, and one that breaks out into 8 multimode fibers.

I see that QSFPP-4X10GE-SR is supported on MX204 since 17.4R1. We're running 19.4R3. *SHOULD* work, right?

With the appropriate configuration they come up and pass data. Great. But they flap every few minutes, and the PFE log is flooded with 

MQSS(0): CHMAC1: Detected Ethernet MAC Local Fault Delta Event for Port 0 (xe-0/0/0:0)
MQSS(0): CHMAC1: Cleared Ethernet MAC Local Fault Delta Event for Port 0 (xe-0/0/0:0)

...for every single channel interface that's got link on it. The same happens with the DACs and AOCs.

Of course, these are all from FS, so firmware is the big question in my mind. These are Fiberstore QFX-QSFP-DACBO-2M and EX-QSFP-8LC-AOC5M. The MX CLI shows them as "QSFP+-40G-CU?M". These are switch-oriented part numbers, but I must admit this is my first foray into these things and in SFP+ land I haven't encountered any issues where an optic labelled "EX" doesn't just work in everything. We don't have an MX204 available to try random JUNOS loads on (yet) so I turn to the collective:

Do FS QSFP+ breakout DACs and AOCs work on this platform? Is there some magic sauce firmware I'm too daft to find?

(I've talked to JTAC, of course they blame the third-party transceiver)

Thanks

Ross