Hi,

I took a CRS328-4C-20S-4S + RM to distribute links in 1gb and 100mb mode (getting rid of media converters in the rack), but I'm having difficulties with the 10/100mb fast ethernet media converters.

I managed to link the CRS with this converter, forcing the negotiation to 100mb Full Duplex, but I still can't see both sides in the Neighbors Lists, ping, etc ...
I'm missing something?

100Mbit over SFP is very special. Not supported on all ports/platforms. Gigabit is the standard.

When using against media converters, disable auto-negotiation and use 1Gbps-FD

See
https://wiki.mikrotik.com/wiki/MikroTik ... ansceivers
and
https://wiki.mikrotik.com/wiki/MikroTik ... iber_links