Upgrade failure from CiviCRM 4.6.x to 5.5.x due to Backup and Migrate module being enabled
I attempted an upgrade from 4.6.38 to 5.5.1 running the database upgrade through Drush. I am on Debian 8. At some point around version 4.7 the upgrade failed. It appears that there were too many connection to the MySQL database server, which I think is set to the standard 100. After consulting an expert, we found that something with the upgrade process was triggering the Drupal Backup and Migrate module to create too many database connections. After reverting to a backup and trying again with Backup and Migrate disabled the upgrade went relatively smoothly. Error text:
PEAR_Exception: "DB Error: connect failed"
- ERROR TYPE: DB_Error
- ERROR CODE: -24
- ERROR MESSAGE: DB Error: connect failed
- ERROR MODE: 16
- ERROR USERINFO: [nativecode=Too many connections]
- ERROR DEBUGINFO: [nativecode=Too many connections]