Proxmox sending emails without any SMTP config

[Disco]

Hello,

This is really strange.

I have setup the latest version of Proxmox VE and just given my email address. Name servers are pointing to Google and the domain is x.y.z.loc, not existing in any DNS.

I have updated crontab -e as root like this

30 5 * * *     root  /usr/bin/pveupdate && /usr/bin/pveupgrade >/dev/null 2>&1
35 3 1-7 * 6    root reboot

Since there is a error in this crontab config, failing command sends me an email alert to my public email every night. How this is possible? There is nothing wrong to get email alerts, I would prefer to get those on failures, but getting email alerts without any configuration is worrying me.

Thanks in advance!