err sSMTP

Ok, my information based on the support ticket. there is one issue that currently if the big-ip wants to send mail and no mail server is configured it uses the default "mail" hostname. there is a bug ID564522 without a fix currently.

of course it doesn't send these emails by accident, if these happen regularly (every minute, 5 minutes, hour) there must be something wrong in the automatically triggered scripts (usually by the cron daemon). the one for my test system i haven't found but for another system is was the issue described here:

https://devcentral.f5.com/questions/just-upgraded-to-121-and-getting-many-cron-emails-47141

that is for bug ID ID578036

for me what modifying /etc/cron.usbflush was not enough, also had to change the root crontab itself. please be careful with workarounds like this if you are not that familiar with linux.