diff --git a/data/conf/postfix/main.cf b/data/conf/postfix/main.cf
index ffdef4c4..e90de183 100644
--- a/data/conf/postfix/main.cf
+++ b/data/conf/postfix/main.cf
@@ -41,7 +41,7 @@ postscreen_non_smtp_command_enable = no
 postscreen_pipelining_enable = no
 proxy_read_maps = proxy:mysql:/opt/postfix/conf/sql/mysql_virtual_sender_acl.cf, proxy:mysql:/opt/postfix/conf/sql/mysql_tls_enforce_out_policy.cf, proxy:mysql:/opt/postfix/conf/sql/mysql_tls_enforce_in_policy.cf, $local_recipient_maps $mydestination $virtual_alias_maps $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains $relay_recipient_maps $relay_domains $canonical_maps $sender_canonical_maps $recipient_canonical_maps $relocated_maps $transport_maps $mynetworks $smtpd_sender_login_maps
 queue_run_delay = 300s
-relay_domains = proxy:mysql:/opt/postfix/conf/sql/mysql_virtual_mxdomain_maps.cf
+relay_domains = proxy:mysql:/opt/postfix/conf/sql/mysql_virtual_relay_domain_maps.cf
 relay_recipient_maps = proxy:mysql:/opt/postfix/conf/sql/mysql_relay_recipient_maps.cf
 sender_dependent_default_transport_maps = proxy:mysql:/opt/postfix/conf/sql/mysql_tls_enforce_out_policy.cf
 smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt
diff --git a/data/conf/postfix/sql/mysql_virtual_mailbox_maps.cf b/data/conf/postfix/sql/mysql_virtual_mailbox_maps.cf
index e370919e..bf07cdb2 100644
--- a/data/conf/postfix/sql/mysql_virtual_mailbox_maps.cf
+++ b/data/conf/postfix/sql/mysql_virtual_mailbox_maps.cf
@@ -2,4 +2,4 @@ user = mailcow
 password = mysafepasswd
 hosts = mysql
 dbname = mailcow
-query           = SELECT maildir FROM mailbox WHERE username='%s' AND active = '1'
+query = SELECT maildir FROM mailbox WHERE username='%s' AND active = '1'
diff --git a/data/conf/postfix/sql/mysql_virtual_relay_domain_maps.cf b/data/conf/postfix/sql/mysql_virtual_relay_domain_maps.cf
new file mode 100644
index 00000000..6994d02d
--- /dev/null
+++ b/data/conf/postfix/sql/mysql_virtual_relay_domain_maps.cf
@@ -0,0 +1,5 @@
+user = mailcow
+password = mysafepasswd
+hosts = mysql
+dbname = mailcow
+query = SELECT domain FROM domain WHERE domain='%s' AND backupmx = '1' AND active = '1'