Upload use all my bandwidth

i am using mikrotik for several time…and now something happening to use all my upload…have even not idea where to check what was happend…
can some give me some ideas…

i was determinite that problem with speedtest where was upload almost 0, download was ok.

This usually means your router is being used in a DDOS attack. Please make sure extenal services such as DNS and NTP are disabled or firewalled from the internet

seems for now was firewall problem…now work fine :wink:

thanks for advice…