Prefetch User Database ====================== Prefetch userdb can be used to combine passdb and userdb lookups into a single lookup. It's usually used with<SQL> [AuthDatabase.SQL.txt], <LDAP> [AuthDatabase.LDAP.txt] and <checkpassword> [PasswordDatabase.CheckPassword.txt] passdbs. Prefetch basically works by requiring that the passdb returns the userdb information in<extra fields> [PasswordDatabase.ExtraFields.txt] with 'userdb_' prefixes. For example if a userdb typically returns 'uid', 'gid' and 'home' fields, the passdb would have to return 'userdb_uid', 'userdb_gid' and 'userdb_home' fields. If you're using <deliver> [LDA.txt], you still need a valid userdb which can be used to locate the users. You can do this by adding a normal SQL/LDAP userdb after the userdb prefetch. See below for examples. LDAP's 'auth_bind_userdn=yes' setting is incompatible with prefetch, because no passdb lookup is done then. If you want zero LDAP lookups, you might want to user<static userdb> [UserDatabase.Static.txt] instead of prefetch. SQL example ----------- 'dovecot.conf': ---%<------------------------------------------------------------------------- passdb sql { args = /etc/dovecot-sql.conf } userdb prefetch { } # The userdb below is used only by deliver. userdb sql { args = /etc/dovecot-sql.conf } ---%<------------------------------------------------------------------------- 'dovecot-sql.conf': ---%<------------------------------------------------------------------------- # NOTE: '\' line splitting is used only for readability, currently Dovecot doesn't support it password_query = SELECT password, \ home AS userdb_home, uid AS userdb_uid, gid AS userdb_gid \ FROM users \ WHERE userid = '%u' # For deliver: user_query = SELECT home, uid, gid FROM users WHERE userid = '%u' ---%<------------------------------------------------------------------------- LDAP example ------------ 'dovecot.conf': ---%<------------------------------------------------------------------------- passdb ldap { args = /etc/dovecot-ldap.conf } userdb prefetch { } # The userdb below is used only by deliver. userdb ldap { args = /etc/dovecot-ldap.conf } ---%<------------------------------------------------------------------------- 'dovecot-ldap.conf': ---%<------------------------------------------------------------------------- # NOTE: '\' line splitting is used only for readability, currently Dovecot doesn't support it pass_attrs = uid=user,userPassword=password, \ homeDirectory=userdb_home,uidNumber=userdb_uid,gidNumber=userdb_gid # For deliver: user_attrs = homeDirectory=home,uidNumber=uid,gidNumber=gid ---%<------------------------------------------------------------------------- (This file was created from the wiki on 2007-06-15 04:42)