"Onionbalance is the best way to load balance onion services across multiple backend Tor instances. This way the load of introduction and rendezvous requests get distributed across multiple hosts. Onionbalance provides load-balancing while also making onion services more resilient and reliable by eliminating single points-of-failure."
"This tool is designed to allow requests to Tor onion service to be directed to multiple back-end Tor instances, thereby increasing availability and reliability. The design involves collating the set of introduction points created by one or more independent Tor onion service instances into a single ‘master’ descriptor."