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Upgrading WPMU

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Upgrading WPMU

You should read through the comprehensive Upgrading_WordPress WP upgrade documentation site before attempting to upgrade WPMU. In summary, we recommend you: 

  # Backup WPMU
  # use the ABC tool to back up as per WP
  # do something or other to adjust for WPMU
  #

Remember to backup your database and files. The link above has instructions to help you do this.

If these instructions are out of date please update them. That's much better than just complaining on the forums.

Check your Version. You can find the version of WPMU by looking at the page source of any page. If you are viewing the site you should see <meta name="generator" content="WordPress 2.5.1" />, keep in mind the WPMU version is deprecated by 1, so 2.5.1 is really 1.5.1.

1.5 to 2.6

The version number is being bumped to 2.6 rather than 1.6 because of version confusion. Minor MU versions will probably append a letter to the version.

1. (instructions needed)

References

  1. http://mu.wordpress.org/forums/topic.php?id=8885
  2. http://ocaoimh.ie/2008/07/09/wordpress-mu-26-beta-1/

1.3.3 to 1.5.1

  1. Backup your files (webmin works great for this or follow Backup WPMU) & disable plugins
  2. Remove all files in your wpmu/ directory, copy new files over (cleaner) KEEP wp-config.php and .htaccess!
  3. Remove directories wp-admin & wp-includes and copy new directories
  4. Replace files in wp-content (index.php and blogs.php)
  5. Copy wp-content/mu-plugins/index.php & wp-content/plugins/index.php
  6. Login to new admin, update wp-config.php with Secret Keys
  7. Login again, run site wide blog upgrades
  8. Congratulations, your done, check your file ownership, and permissions if you have image issues, or upload problems.

1.2 to 1.3

First approach (tested on WPMU 1.2.2 without subdomains):

  1. Create a backup of all files and database
  2. Disable all your plugins
  3. Overwrite your WPMU files with new version files
  4. Check your wp-config.php (edit by hand if needed) and your .htaccess
  5. Login as admin and run Upgrade from "Site Admin -> Upgrade" (this will upgrade your database layout if needed, will take a while on big databases).
  6. Check that all is working properly
  7. Enable your plugins one by one

MU-plugins with known issues:

  • dashboardswitcher.php
  • delete-blog.php
  • misc.php

Changes to Categories handling to support Tagging

This upgrade introduces tagging of posts. New tables, including 3 per blog, are created for this purpose, and are synchronised, during the upgrade process. Reference 1 provides more details. In some cases, such as where the server is heavily loaded or the number of blogs is large, this process has not completed successfully. A beta taxonomy synch script may help in this situation.

References

  1. WordPress 2.3 Taxonomy Schema

Character set issues with early versions of WPMU

WPMU 1.3 assumes your database tables use the utf8 default character set. If you started with an early version (e.g. 1.0 RC4) you may find your tables are defined to use the latin1 default character set. If so, they must be changed to use utf8 prior to the upgrade. Unless this is done, strange symbols (e.g. Â, i.e. A with circumflex) may appear in amongst blog content following the upgrade2 3. The process is described in Reference 1.

References

  1. http://edubuzz.org/blogs/david/wordpress/changing-early-wpmu-db-to-utf8/
  2. WPMU Forum thread: Problems updating from pre 1.3 version
  3. WPMU Forum thread: Upgrade messed up with content

Unresolved issues

An attempt to use code from WPMU 1.3/WP 2.3 generated an error that 'register_sidebar_widget' was not a correct function. A quick search of the WPMU code seems to show a 'wp_register_sidebar_widget' but it appears to have different parameters. Can anyone help?

(Question asked at [[1]]

1.1 to 1.2

Instructions needed

1.0 to 1.1

Instructions needed

Pre 1.0 versions

Post Version 1, RC1

Upgrading a recent version of WPMU from after June 22, 2006 or when Release Candidate 1 was published should be simple enough. 

   * Download the newest version and unzip it somewhere.
   * Shut down the site by stopping Apache. It's easier this way. When you're comfortable with upgrading this step may be skipped.
   * If you haven't modified any files then overwrite your current install with the files from the newer version.
   * If you have modified files you'll have to be careful to not overwrite those files.
   * Examine the new htaccess.dist and compare it to the old ".htaccess" file. Add any new lines and remember that "BASE/" should be replaced with the path to your web site.
   * Restart Apache.
   * You may need to upgrade the databases tables of each blog. This can be done by visiting "Site Admin"->Upgrade while logged in as the site admin. This may take a long time.


Pre Version 1, RC1

Before Version 1, RC1 was released we used a wp-inst directory to hold the core wordpress files so there is more work to do upgrading. 

   * Download the newest version and unzip it somewhere.
   * Shut down your site by stopping Apache. You really should do this as there are so many files moving about.
   * Presuming your site is installed in /home/www/htdocs/:
         o Delete /home/www/htdocs/index.php and /home/www/htdocs/.htaccess
         o Move /home/www/htdocs/wp-inst/* to /home/www/htdocs/
         o If you haven't modified any files then overwrite your current install with the files from the newer version.
         o If you have modified files you'll have to be careful to not overwrite those files.
         o Copy the new /home/www/htdocs/htaccess.dist to /home/www/htdocs/.htaccess and edit .htacces, replacing "BASE/" with the path to your web site. In this case it would probably be "/". 
   * Restart Apache and test, test and test things.
   * You may need to upgrade the databases tables of each blog. This can be done by visiting "Site Admin"->Upgrade while logged in as the site admin. This may take a long time.
   * If you used WPMU with sub-directories prior to June 2006 you will come across a particular problem when upgrading. Read [[2][bug #85]] for more.

If things go wrong you can always restore things from the backup. You did backup all your files and database first? Hang your head in shame if you didn't!

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