An unexpected error occurred. Refer to the logs for more information.

[Richard Troiano]

So here is our setup

We have test, dev and prod environments.   Each confluence instance is a VM running on Ubuntu 22.04.   We use PostgreSQL as the backend database and it is installed on each host.  We are using the .tar.gz installer method to upgrade.

I have successfully updated my dev and test environments to v7.19.5 from 7.19.1, however for some reason in the production VM, after I finish the installer and start Confluence afterwards, when I go to update any of the plugins that show they have updates available I am getting the following error:

An unexpected error occurred. Refer to the logs for more information.

Ok, I can do that - but what log should I be looking into?    What exactly should I be looking for after I figure out what log to look at?   All three VMs are supposedly identical, so this sort of thing should not really be happening.

I should also mention that the first time I login to the admin panel after the upgrade, the upgrade summary says the following regarding user apps

User apps

All enabled apps are available.

All apps are compatible and have started. Apps are managed by the Universal Plugin Manager in Confluence administration.

[Richard Troiano · Accepted solution]

We figured it out.   Just incase anyone else runs into a similar issue, the server in question was being built out to replace an existing RHEL based VM with Ubuntu Server.   Since the production RHEL VM was still in operation, we could not assign the production FQDN to this machine after installing Confluence.   It turns out unless the URL you have specified in the server.xml file matches up exactly with the URL you are accessing the site, installing plugins will fail.   We temporarily created a new DNS entry for the ubuntu based VM, updated the server.xml to point at his new FQDN and afterwards we were able to update the plugins.