Title: Debugging HyperDB
Last modified: August 21, 2016

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# Debugging HyperDB

 *  [plembo](https://wordpress.org/support/users/plembo/)
 * (@plembo)
 * [12 years, 5 months ago](https://wordpress.org/support/topic/debugging-hyperdb/)
 * I am looking for some advice on how to debug an apparently non-functioning deployment
   of HyperDB. With it turned on we can’t make changes.
 * WordPress 3.6.1 files reside on a NAS shared by 2 RHEL 6.4 servers running the
   shipping rpms for php (5.3.3), Apache (2.2) and MySQL (5.1.6) server, with the
   WP install as DocumentRoot. We are using master-slave MySQL replication to provide
   read/write on node1 and read only on node 2. Replication tests good, as does 
   writing and reading to the appropriate node. But if we turn on HyperDB we can’t
   write.
 * Before enabling HyperDB we made sure that a wpdbuser@localhost and wpdbuser@%.
   example.com user existed in mysql.user and that user could log into MySQL from
   either node. Our db-config.php looks like this:
 * `
    $wpdb->add_database(array( 'host' => 'node1.example.com', 'user' => DB_USER,'
   password' => DB_PASSWORD, 'name' => DB_NAME, 'write' => 1, 'read' => 1, )); $
   wpdb->add_database(array( 'host' => DB_HOST, 'user' => DB_USER, 'password' =>
   DB_PASSWORD, 'name' => DB_NAME, 'write' => 0, 'read' => 1, ));
 * I’m looking more for a checklist or basic guidelines for debugging rather than
   a complete solution to my problem, because as we all know whatever bit you today
   is likely to look completely different tomorrow.
 * [http://wordpress.org/plugins/hyperdb/](http://wordpress.org/plugins/hyperdb/)

Viewing 1 replies (of 1 total)

 *  Thread Starter [plembo](https://wordpress.org/support/users/plembo/)
 * (@plembo)
 * [12 years, 1 month ago](https://wordpress.org/support/topic/debugging-hyperdb/#post-4319262)
 * Just to update everyone: I’ve directed that HyperDB be removed from all our sites
   and am now working with our engineering team on developing a MySQL (actually 
   MariaDB Galera) cluster to provide a more reliable (and better documented) solution.

Viewing 1 replies (of 1 total)

The topic ‘Debugging HyperDB’ is closed to new replies.

 * ![](https://s.w.org/plugins/geopattern-icon/hyperdb_33353d.svg)
 * [HyperDB](https://wordpress.org/plugins/hyperdb/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/hyperdb/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/hyperdb/)
 * [Active Topics](https://wordpress.org/support/plugin/hyperdb/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/hyperdb/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/hyperdb/reviews/)

## Tags

 * [debugging](https://wordpress.org/support/topic-tag/debugging/)

 * 1 reply
 * 1 participant
 * Last reply from: [plembo](https://wordpress.org/support/users/plembo/)
 * Last activity: [12 years, 1 month ago](https://wordpress.org/support/topic/debugging-hyperdb/#post-4319262)
 * Status: not resolved