1st Part.
So you can add a column to the Context Selector widget that will have the Parameter Name of ORIGIN or something of that nature. That column can get values from a SQL Data Source or you can manually enter the values you would like to have as options e.g. "ACV" or BIV.
2nd Part.
In a perfect world I would assume that your naming convention is spot on across all domains. For example you would have both a ACVWEB01 and a BIVWEB01 or something along those lines. If you want to create one dashboard that will show the alarm status of both servers based on the Context Selector then you would drop a Image Widget and assign it a Alarm Datastore with a Filter that looks something like this:
Alarm Filter Name: Web Server Alarm
Filter Options:
1st line: "Robot" "contains" "${ORIGIN}
2nd line: "Robot" "contains" "Web"
You could also change the first line to: "Origin" "is" "${ORIGIN}. Depending on your environment one may be better then the other.
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