>> This is going to involve and export / import process. I would do a clean installation of 4.3, and then figure out how to move all the config.
That's correct.
- Install a new 4.3 system with same hostname.
- Migrate apache and SAML cert ( if SAML being used ) manually.
- Pull user's information from old system to new one with Cache Refresh.
- Manually take OpenID client configuration ldap data and push them inside 4.3
- See how things go.