For monitoring ZFS pools, there should be zed (ZFS event daemon) set up by default. In case of noteworthy events it sends an email to the local root user, which is forwarded by the local Postfix instance into our notification stack as an notification event of type system-mail [1].
For anything else you should set up a separate monitoring solution of your choice for your Proxmox VE host, e.g. Netdata, Prometheus, Icinga etc.
We have plans for integrating different kinds of health checks/alerts natively into Proxmox PVE, but there is not ETA for that and it will not likely be a full replacement for a dedicated monitoring solution.
Thank you,
I think I have configured the notification correct, but have not been notified by a ZFS disk failure, some IO errors. As you write that notification should be by default, I will recheck the notification with you link