The content database on the server is temporarily unavailable.

The content database on the server is temporarily unavailable.

When you try to deploy an app via Visual Studio, you might get the this error

Solution

Configure Managed Metadata service application correctly.

Check your domain ip in DNS server.(get your ip from ipconfing from CMD )
Also make sure you have the below service applications configured correctly

1. App Management Service Application.

2. Microsoft SharePoint Foundation Subscription Settings Service Application.

Then i looked in to Event Viewer. I found below problem 

Then I started  the Distributed Cache .

Then i deploy the solution the problem solved. 
:)