Is there an app or docker that can ping all my devices say every hour and if a device is offline it will alert me by email?

you should look at zabbix.com. it's available in the docker too.

Ok where is the docker link for it?

i don't think there will be a docker template for unRAID, but see on github: https://hub.docker.com/r/zabbix/zabbix-appliance/

this docker contains all components needed.

 

i'm using zabbix on top of Ubuntu server.

Ok thanks.

 

Does anyone know what unraid is using for smtp mail on the settings tab, notification settings to send out alerts?

anyone know the above?

How about something like this -

 

ping -q -c1 -w3 server /dev/null || echo server ping failed | mail -ne -s'Server unavailable' emailaddress

 

Will this work? What mail command is used?

UnRaid uses the notify command   /usr/local/emhttp/webGui/scripts/notify    which I found actually easier. Once you set up notifications in the GUI, this just tacks on to the system notifications. You can specify the specifics from the command including severity. No expert here but it wasn't hard to use in a script

Yeah I finally got it working once I figured out to use the notify command.