Major Description
If you configure a couchbase-server with hostname instead of ip (ipv4, you can't enter an ipv6 address via web interface), the .net client library refuses the connection.
The problem is "SocketPool.cs" creates a new socket (method "Create") with "AddressFamily.InterNetwork" (ipv4), but "_node.EndPoint" can be of type "AddressFamily.InterNetworkV6".
The method "GetFirstAddress" within "CouchbasePool.cs" calls "Dns.GetHostAddresses", which returns ipv4 and ipv6 addresses and doesn't filter to ipv4 adresses.
Couchbase-Server has problems with ipv6 (see also http://www.couchbase.com/issues/browse/MB-6378).
The problem was also described in http://www.couchbase.com/communities/q-and-a/net-client-wont-communicate-cluster-successfully-configured-hostnames?current=node/640