<p>We're looking at CouchdDB for a CMS-ish application. What are some common patterns, best practices and workflow advice surrounding backing up our production database?</p>

<p>I'm particularly interested in the process of cloning the database for use in development and testing.</p>

<p>Is it sufficient to just copy the files on disk out from under a live running instance? Can you clone database data between two live running instances?</p>

<p>Advice and description of the techniques you use will be greatly appreciated.</p>

CouchDB supports replication, so just replicate to another instance of CouchDB and backup from there, avoiding disturbing where you write changes to.
https://docs.couchdb.org/en/latest/maintenance/backups.html
You literally send a POST request to your CouchDB instance telling it where to replicate to, and it Works(tm)
EDIT: You can just cp out the .couch files in the data directory from under the running database as long as you can accept the I/O hit.