Alert config

Hello, I always get a lot of help.

If you specify one host.name in the filter, the value of the host is applied (here, 87.5%), and you can set an alarm based on that number. .
I'm trying to set an alarm when any asset exceeds 90%, but if I don't select one asset, it defaults to 100%, so I can't set it. Is there any other way?

In the screenshot you've posted, the value is "90%". Is this the value you're referring to? You should be able to configure it by clicking on the value. Does this work for you?