diff --git a/slapd/Dockerfile b/slapd/Dockerfile
index 7c7e9ea51cc643614aa7ba2180513bc67e857816..2ed2b022cf69f2360f6045330466e2dc5d351812 100644
--- a/slapd/Dockerfile
+++ b/slapd/Dockerfile
@@ -11,6 +11,7 @@ RUN echo 'deb http://deb.debian.org/debian stretch-backports main' > /etc/apt/so
 COPY --chown=root:root entrypoint /
 EXPOSE 389 636
 VOLUME [ "/var/lib/ldap" ]
+VOLUME [ "/run/ldap" ]
 ENV LDAP_URLS="ldap:/// ldapi:/// ldaps:///" \
     SLAPD_DEBUG_LEVEL="NONE"
 ENTRYPOINT [ "/entrypoint" ]
diff --git a/slapd/README.md b/slapd/README.md
index 326c49fbb41bda911890739a8c0c44dd039103f7..f67a1898f45a6094d9b40d74eb70f6958c08ef50 100644
--- a/slapd/README.md
+++ b/slapd/README.md
@@ -2,6 +2,11 @@
 
 > Dockerized OpenLDAP daemon.
 
+## Interfaces exposed
+
+The container exposes TCP ports 389 (LDAP) and 636 (LDAPS) as well as the
+`ldapi` Unix socket in the `/run/slapd` volume.
+
 ## Environment variables
 
 Name | Description | Default value