I would know if filebeat supports the AIX machine? if not how can I send logs from AIX machines to logstash
There's a number of existing threads on this topic. I would encourage you to do a quick search for them as the AIX + Beats status has not changed for it.
I find 2 tools the first is nxlog and the second is this project http://www.bullfreeware.com/pkg?id=4650
So if there are other tools that can facilitate the work please let me know