S3 upload problem?

I am getting this "getaddrinfo: Name or service not known". I think that it is something to do with S3 but I can't tell.

If I drag a file onto upload it looks like it is doing something but the the "drop" image shakes which I assume means failure.

The S3 bucket works with the same credentials in my Transmit FTP app.

Struggling to diagnose this.

Regards
Colin McGowan

Seahorse::Client::NetworkingError in Locomotive::CurrentSiteController#edit
getaddrinfo: Name or service not known

Extracted source (around line #879):
877
878
879
880
881
882

  D "opening connection to #{conn_address}:#{conn_port}..."
  s = Timeout.timeout(@open_timeout, Net::OpenTimeout) {
    TCPSocket.open(conn_address, conn_port, @local_host, @local_port)
  }
  s.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
  D "opened"

Rails.root: /app

Application Trace | Framework Trace | Full Trace
vendor/ruby-2.2.2/lib/ruby/2.2.0/net/http.rb:879:in initialize' vendor/ruby-2.2.2/lib/ruby/2.2.0/net/http.rb:879:in open'
vendor/ruby-2.2.2/lib/ruby/2.2.0/net/http.rb:879:in block in connect' vendor/ruby-2.2.2/lib/ruby/2.2.0/timeout.rb:89:in block in timeout'
vendor/ruby-2.2.2/lib/ruby/2.2.0/timeout.rb:99:in call' vendor/ruby-2.2.2/lib/ruby/2.2.0/timeout.rb:99:in timeout'
vendor/ruby-2.2.2/lib/ruby/2.2.0/net/http.rb:878:in connect' vendor/ruby-2.2.2/lib/ruby/2.2.0/net/http.rb:863:in do_start'
vendor/ruby-2.2.2/lib/ruby/2.2.0/net/http.rb:858:in `start'