diff --git a/roles/nfs-client/tasks/main.yml b/roles/nfs-client/tasks/main.yml
index a309db2..909aa7c 100644
--- a/roles/nfs-client/tasks/main.yml
+++ b/roles/nfs-client/tasks/main.yml
@@ -4,6 +4,12 @@
     name: nfs-utils
     state: installed
 
+- name: configure idmapd
+  lineinfile:
+    path: /etc/idmapd.conf
+    regexp: '^#?Domain\s*=.*'
+    line: "Domain = {{ mail_domain }}"
+
 - name: enable rpc-gssd services
   service:
     name: rpc-gssd