Failed Nextcloud migration from 31.0.13:1 to 33.0.6:2

This is a follow-up to my original topic:

“StartOS 0.4.0.1 - Nextcloud 31.0.13:1 fails with get-ssl-certificate: unknown hostname despite hostname being registered”

The original topic was automatically closed on Aug. 2 without the problem being resolved, so I can no longer reply to it.

I still need assistance. My Nextcloud contains approximately 1.5 TB of data, so I do not want to rebuild, uninstall, reinstall, or manually alter the Nextcloud data without instructions from Start9.

Current situation:

StartOS: 0.4.0.1

Installed Nextcloud: 31.0.13:1 (Legacy)

Available update: 33.0.6:2

Updating repeatedly fails with:

Unknown Error: Error: cannot migrate from 31.0.13:1 to 33.0.6:2

During the original StartOS 0.3.5.1 → 0.4.0.1 migration, StartOS reported:

Services Failed To Migrate — Nextcloud

and:

Migration Failed — Invalid Signature: signature error: Verification equation was not satisfied

Nextcloud currently shows Running, but its Web Interface health check never becomes healthy and remains at:

Nextcloud is initializing

I have SSH access to the server and can provide any command output requested.

Please provide the supported recovery/migration procedure for this Nextcloud installation. I do not want to risk the existing 1.5 TB of Nextcloud data by experimenting further.

Original closed topic:
https://community.start9.com/t/startos-0-4-0-1-nextcloud-31-0-13-1-fails-with-get-ssl-certificate-unknown-hostname-despite-hostname-being-registered/5472

You cannot skip major versions when updating Nextcloud.

You need to go from v31 to v32, then to v33.

Got to the Marketplace, find Nextcloud, click on “Version” and you will see v32.

Keep in mind that having all services up to their latest version was highly recommended before updating from StartOS 0351 to 0401.