Schengen mean that every persone that arrive on a Schengen protocol country for example the italy can go to france without that someone ask the identity card or a paperwork. Now most if not all of the refuges want to go in the north europe (UK, norway,sweden , Belgium ecc).
But until there little quantity of refuges the nord country welcome them but with a largest numbers of refuges the Welfare become crippled and decided to dont accept another quantity of people.
In the UK that stay in europe but decided to dont accept the euro,decided with the france to sospend Schengen and re put the control on the borse.

Now if a single state can decide to sospend Schengen the other Step will be to go out from the euro for economic reasons.

So the European Union Shows that until the things go well every state stay ok but after the things go wrong the EU was a nutshell.
Sad but true.