[DATABASE]

[DATABASE]
  DB_HOST = localhost
  DB_PORT = 3306
  DB_USER = anonymous
  DB_PASS =

  DB_SESSION_HOST = localhost
  DB_SESSION_PORT = 3306
  DB_SESSION_USER = ensrw
  DB_SESSION_PASS = ensrw

  DB_FALLBACK_HOST = mysql-eg-publicsql.ebi.ac.uk
  DB_FALLBACK_PORT = 4157
  DB_FALLBACK_USER = anonymous
  DB_FALLBACK_PASS =

  DB_FALLBACK2_HOST = ensembldb.ensembl.org
  DB_FALLBACK2_PORT = 3306
  DB_FALLBACK2_USER = anonymous
  DB_FALLBACK2_PASS =

Four subsections with DB_[*_]HOST, DB_[*_]PORT, DB_[*_]USER and DB_[*_]PASS variables specify connection settings for:

• DB_HOST etc. - the primary database host with species/multi-species databases.
• DB_SESSION_HOST etc. - user-specific information, typically the only database to require read-write access and therefore a password protected connection.
• DB_FALLBACK_HOST etc. - to reduce the amount of locally hosted data, it is often desirable to use alternate sources for some databases, the DB_FALLBACK_HOST host will be queried to find any required databases that are not available on DB_HOST
• DB_FALLBACK2_HOST etc. - especially with EnsemblGenomes sites, remote databases may be found on more than one host, the DB_FALLBACK2_HOST host will be queried to find any required databases that are not available on DB_HOST or DB_FALLBACK_HOST