Migration path for Tine 2.0 Community Edition

Although there is a official wiki entry for updating Tine 2.0 I started to document my own experiences here. Most of it is based on practical experiences I collected supporting others. Keep in mind that the update process modifies the database only, you have to make sure that you really removed all old files and replaced it by the whole new package. Since Updates are not revertible, backup your db beforehand or even better try with an exact duplicate of your production database for a "dry run".

Have in mind that, although there is no support for community edition, you won't find help for legacy installations. Updating regular is at least a necessity (usually biggest problems are the result of installations that have been updated for years).

Standard procedure: In general, for recent as well as legacy installations,

you start by doing the last minor update of one line (201x.xx.XX) until the last officially published minor is reached.
After that (2) upgrade to the next major version (201x.XX.xx) using the latest minor of the current release (major version).

However, no rule without excemption. If you can't access the CLI you may be better of to take some minor versions on the way. In casesof bigger db changes the duration may exceed your webservers (or proxies) maximum runtime for scripts.

Theoretical example (at the begging of the time of writing): Update from 2016.09.3 to 2016.09.9 and then upgrade from 2016.09.9 to 2017.02.3.

The following list remarks known specialities regarding each release. Follow the general rule if you don't see dissenting advice. Today we use the numbered format earlier the releases were more often called by its name (children name).

Upgrading legacy installations

The general rule above (update until the last minor) usually does not apply to historic installations. When you are here, you may install any earlier release major to update/upgrade a legacy installation
2014.09.12 was reported to update (minor 12 indicates a well hung software), keep in mind that long runtimes may occur
If you can aquire 2014.09.12 try to start here, you may skip releases 2013.03.x and 2013.10.x

Upgrading to 2015.07

2015.07.4 is known to update from 2014.09.12 flawlessly, you may omit 2014.11 probably
You can even try to start here for legacy releases

Upgrading to 2015.11

Someone reported that he skipped this release completly during a full legacy update
Although this release is mentioned in the official migration path

Upgrading to 2016.03

This release was the last before forking the 2016.11 Business Edition
2016.03.4 was reported to be stable

Upgrading to 2016.09

Due to some known minor incidents update to 2016.09.6 before going further

Upgrading to 2017.02

In my remeberance 2017.02.4 was very stable, I used it long time
In the late release cycle shortly before 2017.08 some problems occured which - in my impression - caused later difficulties at upgrades
At least if you are on 2017.02.5 do not upgrade to earlier releases of 2017.08 (only a vague feeling)
If you come into trouble see comments in Bug #13534 (direct link)
There is a bug which couldn't be reproduce because it became known later (with the next release but I have seen it before): Bug #13508 Tinebase is set to Version 2

Upgrading to 2017.08

You should be at least at version 2017.02.3
Do not update to 2017.08.1 or 2017.08.2
Best known upgrade from 2017.02.x is 2017.08.3 (use it as intermediate)
If for any reason necessary try to upgrade to from 2017.07.5 to 2017.08.6
Within 2017.08.x updates from 2017.08.3 to 2017.08.10 are known as working
Hint: Running 2017.08.3 or later update directly to latest minor version

Upgrading to 2018.02

Update to 2018.02.6 from 2017.08.11, do not use the latest 2018.02.7
I ran 2018.02.4 for a long time, very stable and used 2018.02.6 only for the purpose of updates (minor UI issues)

Upgrading to 2018.08

Starting point is 2018.02.6 (not the very latest minor!), updated directly to 2018.08.3
There is a minor issue in 2018.08.02, didn't try to update 2018.08.1
Long-time tested 2018.08.8 (some issues with calendar/invitations)
Useful to do update to 2018.08.9 before major, because DB scheme is changed and duplicates may occur

Upgrading to 2019.02

Update from 2018.08.9 directly to 2019.02.2 (careful, 2019.02.1 is broken)
Since 2019.02 support for PHP < 7.0, MySQL < 5.7.5 and MariaDB < 10.0. is dropped!