diff --git a/xCAT-server/lib/xcat/plugins/mknb.pm b/xCAT-server/lib/xcat/plugins/mknb.pm
index 9facd7ff8..21253dd49 100644
--- a/xCAT-server/lib/xcat/plugins/mknb.pm
+++ b/xCAT-server/lib/xcat/plugins/mknb.pm
@@ -38,12 +38,27 @@ sub _select_network_addresses {
     return (\%legacy, \%selected);
 }
 
-sub _prebuilt_genesis_requested {
+sub _genesis_export_manifest_present {
     my ($directory) = @_;
     my $manifest = "$directory/$GENESIS_EXPORT_MANIFEST";
     return -e $manifest || -l $manifest;
 }
 
+sub _prebuilt_genesis_requested {
+    my ($directory) = @_;
+    foreach my $name (
+        $GENESIS_EXPORT_MANIFEST,
+        'kernel',
+        'initramfs.cpio.gz',
+        'SHA256SUMS'
+      )
+    {
+        my $path = "$directory/$name";
+        return 0 unless -e $path || -l $path;
+    }
+    return 1;
+}
+
 sub _validate_prebuilt_genesis_manifest {
     my ($directory, $arch) = @_;
     my $manifest = "$directory/$GENESIS_EXPORT_MANIFEST";
@@ -353,6 +368,13 @@ sub process_request {
         $invisibletouch = 1;
         goto CREAT_CONF_FILE;
     }
+    if (_genesis_export_manifest_present($genesis_dir)) {
+        $callback->({
+            error => ["Incomplete Genesis export: $genesis_dir"],
+            errorcode => [1],
+        });
+        return;
+    }
     # Grab all the standard ssh public keys we can
     my @ssh_pub_keys = ();
     if (-r "/root/.ssh/id_rsa.pub") {
diff --git a/xCAT-test/unit/mknb_exported_genesis.t b/xCAT-test/unit/mknb_exported_genesis.t
index 272b3e852..c864b4a2e 100644
--- a/xCAT-test/unit/mknb_exported_genesis.t
+++ b/xCAT-test/unit/mknb_exported_genesis.t
@@ -158,8 +158,12 @@ write_file(
     export_manifest('x86_64'),
 );
 ok(
-    xCAT_plugin::mknb::_prebuilt_genesis_requested($partial_export),
-    'a partial export still selects the prebuilt path',
+    !xCAT_plugin::mknb::_prebuilt_genesis_requested($partial_export),
+    'a partial export does not satisfy the prebuilt layout',
+);
+ok(
+    xCAT_plugin::mknb::_genesis_export_manifest_present($partial_export),
+    'a partial export still declares the new format',
 );
 (undef, $install_error) = xCAT_plugin::mknb::_install_prebuilt_genesis(
     $partial_export, $tftpdir, 'x86_64'
@@ -303,4 +307,29 @@ ok(
     'mknb writes boot configuration after publishing the export',
 );
 
+unlink("$process_export/SHA256SUMS");
+@responses = ();
+xCAT_plugin::mknb::process_request(
+    { arg => ['ppc64'] },
+    sub { push(@responses, @_); },
+);
+ok(
+    grep(
+        { ref($_) eq 'HASH' && $_->{error}
+              && $_->{error}->[0] =~ /Incomplete Genesis export/ }
+          @responses
+    ),
+    'mknb rejects an incomplete marked export',
+);
+is(
+    read_file($process_kernel),
+    'process kernel',
+    'an incomplete marked export keeps the published kernel',
+);
+is(
+    read_file($process_initramfs),
+    'process initramfs',
+    'an incomplete marked export keeps the published initramfs',
+);
+
 done_testing();