diff --git a/src/ldap.js b/src/ldap.js
index 4d11e3daf..a881e572a 100644
--- a/src/ldap.js
+++ b/src/ldap.js
@@ -305,13 +305,14 @@ function mailAliasSearch(req, res, next) {
 
         // https://wiki.debian.org/LDAP/MigrationTools/Examples
         // https://docs.oracle.com/cd/E19455-01/806-5580/6jej518pp/index.html
+        // member is fully qualified - https://docs.oracle.com/cd/E19957-01/816-6082-10/chap4.doc.html#43314
         var obj = {
             dn: req.dn.toString(),
             attributes: {
                 objectclass: ['nisMailAlias'],
                 objectcategory: 'nisMailAlias',
-                cn: alias.name,
-                rfc822MailMember: alias.aliasTarget
+                cn: `${alias.name}@${alias.domain}`,
+                rfc822MailMember: `${alias.aliasTarget}@${alias.domain}`
             }
         };
 
diff --git a/src/test/ldap-test.js b/src/test/ldap-test.js
index 96daad05c..d21118769 100644
--- a/src/test/ldap-test.js
+++ b/src/test/ldap-test.js
@@ -765,8 +765,8 @@ describe('Ldap', function () {
             ldapSearch('cn=' + USER_0_ALIAS + '@example.com,ou=mailaliases,dc=cloudron', 'objectclass=nismailalias', function (error, entries) {
                 if (error) return done(error);
                 expect(entries.length).to.equal(1);
-                expect(entries[0].cn).to.equal('asterix');
-                expect(entries[0].rfc822MailMember).to.equal(USER_0.username.toLowerCase());
+                expect(entries[0].cn).to.equal('asterix@example.com');
+                expect(entries[0].rfc822MailMember).to.equal(USER_0.username.toLowerCase() + '@example.com');
                 done();
             });
         });
@@ -791,8 +791,8 @@ describe('Ldap', function () {
             ldapSearch('cn=' + USER_0_ALIAS + '@example.com,ou=mailaliases,dc=cloudron', 'objectclass=nismailalias', function (error, entries) {
                 if (error) return done(error);
                 expect(entries.length).to.equal(1);
-                expect(entries[0].cn).to.equal('asterix');
-                expect(entries[0].rfc822MailMember).to.equal(USER_0.username.toLowerCase());
+                expect(entries[0].cn).to.equal('asterix@example.com');
+                expect(entries[0].rfc822MailMember).to.equal(USER_0.username.toLowerCase() + '@example.com');
                 done();
             });
         });