Is possible with DDNS work with remote log? example: in log action remote address: pippo.dyndns.org
when I apply all ok, it does not work when changing ip. You can "disable" DNS Lookup...or refresh?

My English is not perfect? I do not answer!

no you cannot setup syslog to a hostname. You can setup a script that updates it periodically if you wish. There are samples in the forums many times if you search.

tank changeip. I read in the forum. I did not find many topics. You can give me help? For me difficult language in the script

Really simple, thanks to the support Mikrotik:
/system logging action set remote remote=[:resolve "pippo.dyndns.org"];
in schedule.
Thank Mikrotik