Has anyone actually been able to pull this off? Upgrade a production site from Drupal 6.x to Drupal 7.x without any hitches? Or is this whole process still being ironed out?
I tried it on one of 8 different sites that I have to do and even after following the UPGRADE.TXT file closely, I failed miserably. Error after error after error : (
To make matters worse, once I gave up and restored the site, now it's full of errors that didnt exist before because the upgrade process left all sorts of tables in the database that 6.22 doesnt recognize.
Also restore doesnt seem to be able to remove several 7.x files from site and practically all the modules.
I'm not sure if these files are getting left behind after a restore because the restore process extracts a tarball, and since those files didn't exist they are over looked in the overwrite process or what. But this whole migration has turned out to be a nasty nasty nightmare that I'm wishing I would have never attempted.
One of the notes says not to try to run update.php multiple times during an upgrade if errors or failures exist, which means restoring and starting over, which I have done over a half a dozen times to no avail.
Should I be trying to upgrade from 6.22 to 7.0 first? And then on to 7.2? Or is this not an issue?
Ready to give up and throw in the towel.
Comments
use your exact error messages
use your exact error messages for googeling about the upgrade. so many people have upgraded successfully - look how the others succeed.
I had a lot of problems
I had a lot of problems upgrading. Lot's of problems with the database and various errors like you had. Luckily I did it on a low priority site. What I learned is that there is NO WAY I am upgrading my more important sites. Not any time soon anyways.
v7 simply is NOT ready yet. There isn't even a production read token module for it yet.
btw, I followed the instructions on this site exactly but still I had all kinds of problems. To this day the new v7 site still has problems. Ended up having to change themes and all sorts of things. My advice is don't do it. Wait till v7 and the upgrade instructions mature more.
I wondered about that
I had a feeling 7.0 was a little green yet to think these upgrades would go off without a hitch. Luckily my first and hopefully my worst experience here with that was on a smaller scale site as you mentioned. Now I'll be removing that site completely and totally rebuilding it for the client just to get it back to normal.
I wont be attempting this on any of my more important sites any time soon. No wayyy!
I join the club. Upgrading
I join the club. Upgrading from D6 to D7 is an extremely fragile procedure, which is not acceptable for the core (it may be for modules and themes). I have tried the upgrade path from the latest Drupal 6 to 7.4 repeatedly on the same test database: on the first attempt, after fighting against a few errors (for example, I had to manually truncate the “sessions” table in the database and delete leftovers from the “variable” table), the core upgrade succeeded (by chance, then I discovered): from there, updating the modules was not painless, but no more problematic than expected (because you /expect/ it that it will be problematic). Starting from the next day, whatever I try I cannot update the core any longer; I get errors that are supposed to be fixed (e.g., #730600, #989560). God knows what combination of disabled modules, uninstalled modules, deleted modules, removed orphaned actions, rebuilt permissions, cleaned caches, theme resetting, drush commands, SQL commands and git branching I did the first time—I cannot reproduce a correct upgrade process.
Sadly, a safer (and possibly faster) way to move to D7 is the following: make a fresh installation of D7 and import/paste/rebuild content from your old web site.
Upgrading more problematic if the DBMS is not MySQL
On reading #1006478: Race condition in the update process causes random test bot failures (e.g., #29: “If PostgreSQL was properly supported in Drupal 6, the upgrade path between Drupal 6 and Drupal 7 could be critical. But it wasn't, and nobody ever cared about PostgreSQL during the Drupal 6 era.” and #35: “We are not holding up a release of software for a million+ people over a broken upgrade path that affects ~100 people, at best. Period.”) and #710858: Meta issue: fix the remaining PostgreSQL bugs (still active at the time of this writing), one gets the vague impression that, despite the requirements statement, Drupal really works only with MySQL, the other DBMSs (PostgreSQL, in this case) not being cared much.
_
Some good info on the upgrade process: http://www.lullabot.com/articles/tales-d7-front.
Plan A and plan B
That's a really useful article from Lullabot. A major upgrade like D6 -> D7 should be tried first on a copy of the site, not on the production site.
And, in the case of unsatisfactory results, there is plan B (export/import content), as mentioned on this thread by druido:
Tables left behind after restore
If you decide to drop back to version 6 after an attempted upgrade to version 7 make sure that you drop your database first, then recreate it followed by a restore.
drop database xxx
create database xxx
The upgrade creates new tables in your database and these are not overwritten automatically because they are unknown to version 6, they are left behind.
Following this procedure you will be back to normal with version 6.
Nigtmare
I did upgrade to version 6.12 to 6.22, but when I tried to do for 7.0 nothing worked.