Upgrade without any downtime ============================ Before migration to systemd, the nginx initscript provided the ability to upgrade the running nginx server without any downtime. This functionality has now been replaced with a downstream shell script, located at /usr/bin/nginx-upgrade. Following an update to nginx via the package manager, running nginx-upgrade will cause a new nginx master to be created, which will then take all new requests. The old master and workers are then gracefully shutdown without breaking any existing connections. See http://wiki.nginx.org/CommandLine for more information.