We want to relay mails from the container to localhost (the LXC host mail system)

lxc-php/tasks/php.yml

@@ -88,10 +88,10 @@
   when: name != 'php73'
 
 - name: Configure opensmtpd
-  replace:
-    name: "/var/lib/lxc/{{name}}/rootfs/etc/smtpd.conf"
-    regexp: "^listen.*"
-    replace: "#listen on localhost"
+  template:
+    src: smtpd.conf.j2
+    dest: "/var/lib/lxc/{{name}}/rootfs/etc/smtpd.conf"
+    mode: "0644"
   notify: "Restart opensmtpd"
   when: name == 'php73'
 

lxc-php/templates/smtpd.conf.j2

@@ -0,0 +1,14 @@
+# This is the smtpd server system-wide configuration file.
+# See smtpd.conf(5) for more information.
+
+# To accept external mail, replace with: listen on all
+#listen on localhost
+
+# If you edit the file, you have to run "smtpctl update table aliases"
+table aliases file:/etc/aliases
+
+# Uncomment the following to accept external mail for domain "example.org"
+#accept from any for domain "example.org" alias <aliases> deliver to mbox
+
+accept for local alias <aliases> deliver to mbox
+accept for any relay via "smtp://127.0.0.1"