How to troubleshoot this, consistent error:
Error connecting to Redis on localhost:6379 (Errno::EADDRNOTAVAIL) subscribe failed, reconnecting in 1 second. Call stack ["/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:362:in `rescue in establish_connection'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:343:in `establish_connection'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:106:in `block in connect'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:306:in `with_reconnect'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:105:in `connect'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:381:in `ensure_connected'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:231:in `block in process'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:319:in `logging'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:230:in `process'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis/client.rb:125:in `call'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis.rb:914:in `block in get'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis.rb:52:in `block in synchronize'", "/usr/local/lib/ruby/2.6.0/monitor.rb:235:in `mon_synchronize'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis.rb:52:in `synchronize'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/redis-4.1.3/lib/redis.rb:913:in `get'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/message_bus-2.2.4/lib/message_bus/backends/redis.rb:360:in `process_global_backlog'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/message_bus-2.2.4/lib/message_bus/backends/redis.rb:271:in `block in global_subscribe'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/message_bus-2.2.4/lib/message_bus/backends/redis.rb:284:in `global_subscribe'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/message_bus-2.2.4/lib/message_bus.rb:721:in `global_subscribe_thread'", "/var/www/discourse/vendor/bundle/ruby/2.6.0/gems/message_bus-2.2.4/lib/message_bus.rb:669:in `block in new_subscriber_thread'"]