insurance requirement for commercial tenant

[James Park]

Hello! 

need a little help please. I have a mix use building in CT. the ground floor tenant is a bar/restaurant that recently moved in. 

they got a $2M General liability insurance and is asking if that's enough. or if they should get an umbrella. the property is valued at around $700k, fyi. 

where can i read up on best practices for such a case? or does anyone have experience? 

thank you

J