Sendind fail2ban emails fails on ncp v1.50.3

Just installed a fresh instance of ncp v1.50.3 with a Raspi Image. All good. I set up email notification via nextcloud and smtp. This works great. At the ncp ui, I activated notification emails for fail2ban. They fail.
I believe the smtp settings are not correctly passed over to postfix.
my mail.log shows they are still trying to send from the default. ( I believe the sender credentials are not passed over to postfix.
I have no idea where to set them.
Please help. Thanks!

*edit: typo

I’m unable to check this directly on a ncp instance at the moment, sorry, if I’m not completely mistaken you can find it in the files at the locations written here

Thanks! I looked thrue there and googled around, but was not really able to change the default.
Is it correct to create sendmail-whois-lines.local

and add:

Destination/Addressee of the mail

dest =

Sender of the mail

sender =

? Sorry if this is a silly question.
I anybody could hint me to a good guide where and how to set the defaults for sendmail, I´d be very thankful. Ideally It would be great to set this in th ncp web-ui.

The wiki for fail2ban sendmail configuration can be found here :slightly_smiling_face: I don’t know but I think it’s the bottom part you need

Hello @5dnuQoXPU,

i found the same error entries in /var/log/mail.log.

I found the sender E-Mail address “” in /etc/fail2ban/jail.local. I have changed them right now and restarted the service with “sudo service fail2ban status”, hoping, that the error is now solved.

If I do not forget it, I will check it again in a view days, and tell you the result.