Add layer tag to virt_lans table to allow specification of topologies

at different layers. Defaults to 2 in the DB.

sql/database-create.sql

@@ -3785,6 +3785,7 @@ CREATE TABLE `virt_lans` (
   `trace_endnode` tinyint(1) NOT NULL default '0',
   `trace_db` tinyint(1) NOT NULL default '0',
   `fixed_iface` varchar(128) default '',
+  `layer` tinyint(4) NOT NULL default '2',
   PRIMARY KEY  (`exptidx`,`vname`,`vnode`,`vport`),
   UNIQUE KEY `vport` (`pid`,`eid`,`vname`,`vnode`,`vport`),
   KEY `pid` (`pid`,`eid`,`vname`),

sql/updates/4/198

+use strict;
+use libdb;
+
+#
+# MLE stuff
+#
+sub DoUpdate($$$)
+{
+    my ($dbhandle, $dbname, $version) = @_;
+
+    if (!DBSlotExists("virt_lans", "layer")) {
+	DBQueryFatal("alter table virt_lans add ".
+		     " `layer` tinyint(4) NOT NULL default '2'");
+    }
+    return 0;
+}
+1;
+