Upgrade from Horde 5 / PEAR

Horde 5 is supposed to run on PHP 5.x - 7.4 and Horde 6 is supposed to run on PHP 7.4 - 8.x.
Also, the filesystem structure of Horde 6 is different. It is recommended NOT to run an inplace upgrade but backup all assets and start

Prerequisites

- Copy existing installation's database to a new database. At the end of the installation the schema will be changed and no longer fit for Horde 5.
- Go to all Horde 5 apps, including horde base, and safe files like
- registry.local.php
- conf.php
- prefs.local.php
- hooks.php
- attributes.local.php
- backends.local.php
- basically *.local.php
- registry.d/*

You normally don't need to keep these:
- conf.xml
- prefs.php
- backends.php
- attributes.php

These come with the code.
Modifying these was not advisable even in horde 5.

Web Server Config

The Web server's webroot needs to point to the /web subdirectory of the root project, not the top directory of the root project.
See fresh install docs for more detail.

Setup a root project

git clone https://github.com/maintaina-com/horde-deployment.git

Copy Horde configs

Mind the different structure:

old: horde/config/conf.php
new: var/config/horde/conf.php
old: horde/config/*.local.php
new: var/config/horde/
old: horde/config/registry.d
new: var/config/horde/registry.d/

old: horde/nag/conf.php
new: var/config/nag/conf.php
old: horde/nag/config/*.local.php
new: var/config/nag/*.local.php

etc

Editing registry

If your registry.local.php or registry.d/ snippet contains hardcoded webroot or fileroot, comment out these lines.

Install Horde 6

Install the base app

composer install

Install additional apps

composer require horde/kronolith ^5
composer require horde/turba ^5
composer require horde/passwd ^6
composer require horde/mnemo ^5
composer require horde/content ^3
composer require horde/timeobjects ^3
composer require horde/imp ^7
composer require horde/nag ^5
composer require horde/activesync v3.0.0.alpha4

etc ... see the installing chapter for more details on this step.

Upgrade the database

./vendor/bin/horde-db-migrate up

Check the Web UI for configs that need upgrading

Goto the horde/admin/config screen. Check for all apps if there are new settings which need configuration.