Hi,
i've tried to upgrade the firmware of this device.
after the reboot no ethernet find

[admin@MikroTik] > /int pr
Flags: D - dynamic, X - disabled, R - running, S - slave
# NAME TYPE ACTUAL-MTU L2MTU MAX-L2MTU MAC-ADDRESS

i'm connected via serial port

i've tried to reset config without result

is it happen at someone else?

This does not look like The Dude related problem and must be something specific. Please write us email to support@mikrotik.com.