When is request failed this can be due to several problems :

• network down
• server down
• network timeout
• authentication timeout

Instead of directly asking the user, we should display a waiting message to try to determine the reason.
During this time, we should launch another request to a know pipeline that will allow to detect if server was restarted (reason 2) or if authentication is off (reason 4) or finally if this is a network issue (1 or 3) and we could associate different behavior

we should think in preloading