diff --git a/postfix/main.cf b/postfix/main.cf
index 776ee6c..a081c9c 100644
--- a/postfix/main.cf
+++ b/postfix/main.cf
@@ -12,7 +12,7 @@ mynetworks_style = host
 alias_database = $alias_maps
 home_mailbox = Mail/
 smtpd_banner = $myhostname ESMTP $mail_name ($mail_version)
-alias_maps = hash:/etc/postfix/aliases
+alias_maps = lmdb:/etc/postfix/aliases
 queue_directory = /var/spool/postfix
 command_directory = /usr/bin
 daemon_directory = /usr/lib/postfix/bin