I was reading the recommendations for membase in the cloud at http://techzone.couchbase.com/wiki/display/membase/Using+Membase+in+the+... and I have a question about that. If your hostnames are bound by their dns name instead of IP, how big of a dependancy on DNS does that create? If the DNS server is unavailable, do things immediately start failing or are the lookups cached? If it is heavily linked to DNS, how hard is the DNS server going to be hit. If it's cached, how is that cache cleared when the server address changes?