I am asking as my Dogue de Bordeaux will not wake up for anything basically & is therefore quite the terrible guard dog. My neighbors Cane Corso is not as bad but has similar tendencies.

It confuses me since I know Mastiffs were originally bred to be guard dogs & I think many people also get them for guarding purposes? (I didn't)

I don't want my Dogue to be super aggressive about the guarding but all my non Mastiff dogs have at least alerted me somehow that someone is at the door without having been trained to do this. My Dogue won't say anything, some harmless people have entered the house before without me noticing and he just slept through it or looked at them for a bit. And since my non Mastiff is pretty old (and there are break ins in my area sometimes) I would like to train the Dogue to guard a bit but I am not sure it's suitable for his personality I guess...

Does anyone else have a Mastiff like this?