Unifi no longer works because mongodb refuses to start

[IThoughtTooLongForThis]

I'm using the unifi8 package which depends on mongodb60.
The Unifi controller starts but cannot connect to mongodb because mongodb crashes at startup.

I've tried reinstalling and rebooting with no luck.
I tried installing the externaldb version of unifi with mongodb70 with the same issue.

 

[jbo@]

Did you update from a previous unifi version? Did you check the UPDATING message?

2024-06-06
Affects: users of net-mgmt/unifi8
Author: ronald@FreeBSD.org
Reason:
  The default MongoDB version dependency has been switched from 5.0 to 6.0.
  Although MongoDB 5.0 -> MongoDB 6.0 datafiles in-place upgrade seem to
  work, users are strongly recommended to take full backup of unifi
  database prior to upgrade and start with clean installation afterwards.

  For an in-place upgrade it is important that the MongoDB
  'featureCompatibilityVersion' is set to 5.0.
  See: https://www.mongodb.com/docs/v6.0/release-notes/6.0-upgrade-standalone/#feature-compatibility-version
  Run these commands in mongodb50 before upgrading (e.g. while unifi is running):
  $ mongo --port 27117
  > db.adminCommand( { setFeatureCompatibilityVersion: "5.0" } )
  > exit

  See updating entry 20230310 for a backup/restore upgrade.