This article applies to all JSDR software versions.
After a JetStream DR upgrade has been started from the MSA using the command js_upgrade.py upgrade -v it creates the a file /tmp/last_upgrade.log that lists details about the upgrade.
The upgrade command can be run with the -v option to expose more details:
Refer to the following article for information about upgrading the JetStream Management Server Appliance: https://jetstreamsoft.com/portal/jetstream-knowledge-base/upgrade-management-server-appliance-msa/