Progress Sonic 8.5 Installation and Upgrade Guide - Product ...

Chapter 8: Upgrading from 7.5 or 7.6 to 8.5
Zero-Downtime Upgrades of 7.5 and 7.6 Clusters and
Replicated Brokers
In version 7, upgrades could not be applied to a running cluster or replicated brokers. You
had to stop all the brokers, then upgrade them as a unit. For clustered brokers, it meant
that the entire node was out briefly, all the configurations were forced to upgrade, and that
the node did not return to full force until all the member broker installations had been
upgraded. For replicated brokers, it meant that the peers were both offline until they were
both upgraded.
In version 8, the Launcher installed on every system that runs components in the domain
means that administrators will never have to run upgrade software on each system ever
again. The Domain Manager is where the upgrade takes place. Then, the Domain
Manager provisions the remote systems with the upgraded software.
The transition from version 7 to version 8 does require installation of the 8.5 Launcher on
each system to establish participation in the new paradigm. And it does require running
some scripted tasks to complete the change for each container, hosted component, and
data store.
Sonic 8.5 simplifies the upgrade of clusters and replicated brokers by enabling a Sonic 8.5
domain to tolerate both version 7 and version 8 brokers cooperating in different versions.
You install a Launcher on a system where a broker member is running, extract its
configuration from the domain, and then run a smart upgrade that stops the version 7
broker at the moment when it needs perform database actions, and then restarts the broker
as a 8.5 container. That provides administrators with a resilient non-stop topology that can
be fully upgraded from version 7 to 8.5 at a more measured pace. You don’t have to have
administrators all dispersed at systems that host participating cluster members or
replicated peers, trying to orchestrate a simultaneous upgrade event.
The upgrade functions on distributed hosts require that the Domain Manager has been
upgraded to 8.5. Administrative tools must also be Version 8 to monitor the Domain but
have no actual role in the upgrade process.
The upgrade process first connects to the 8.5 Domain Manager to extract the 7.5 or 7.6
configuration, and then to upgrade the configuration and provision the 8.5 installation
location with the appropriate 8.5 functionality.
206 Progress Sonic Installation and Upgrade Guide 8.5