I upgrade all my installation of ELA to 6.1 version. On two one I have this problem:
hosts show always 0 log. If I create a report there is no data. But if I click on "show last 10 event" on home page (last right icon), the last 10 event are correctly displayed. If I look at Host Detail page the "last message on" are correct. If I search on filesystem on the directory for the archived files I find it. So it seems that data are present but they are not correctly displayed.