I wanted to share the good news: our main oVirt instance in PHX is now running the latest 4.2.0 release candidate. This is a Hosted Engine setup that went through lots of updates and hosts most of the services for the project such as the entire CI setup, package repositories, mailing lists and lots of other stuff across hundreds of VMs and a dozen of hosts.

During this upgrade we've tested multiple components since our setup uses many of the customization options offered by oVirt: unusual network configurations, resource quotas, local and shared storage domains and even uncommon hardware architectures such as POWER8.

We faced some problems with Hosted Engine during the upgrade since our environment was deployed way back as 3.4 and HE changed a lot since. Short upgrade guidance:

1) no HE -> just upgrade and enjoy

2) HE on a system that was initially deployed as 4.0 or 4.1 -> upgrade HE hosts, then - the engine

3) HE on a system that was initially deployed before 4.0 -> check out [1] to confirm if HE configs are OK, then upgrade HE hosts, then - the engine

I've reported several bugs during the course of this upgrade and most of them are fixed by now. Hopefully this effort will make your upgrades go smoothly. If you hit any issues with 4.2 - please file bugs as well or start a discussion on the list.

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