diff --git a/Dockerfile b/Dockerfile
index d4674bb..fb2be6c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -86,7 +86,8 @@ RUN echo "_dev_null: /dev/null" > /etc/aliases \
      scache/unix/chroot=n
 
 ADD confd /etc/confd/
-VOLUME /etc/postfix /ssl
+
+VOLUME ["/etc/postfix","/ssl","/var/spool/postfix"]
 EXPOSE 25/tcp 587/tcp
 
 CMD ["postfix","start-fg"]