My team uses consul for service discovery. Can we plug Consul into Rancher, or would we just use Conul manage it ourselves? Or is Rancher discovery really Consul under the hood? 
Rancher metadata and dns are not Consul, so you manage it yourself if you want it. @cloudnautique has something to import rancher-metadata into consul or etcd I think?
We have a confd backend which reads metadata and creates template files. I have also been playing with a little tool that can take a yaml file and create key values to be inserted into a data store… I really only tried etcd. Just out of curiosity which features of Consul are you using?