--- a/bin/pvl.hosts-lldp	Tue Mar 18 00:16:38 2014 +0200
+++ b/bin/pvl.hosts-lldp	Tue Mar 18 00:29:56 2014 +0200
@@ -186,7 +186,10 @@
         if src_name in nodes :
             src = nodes[src_name]
         else :
-            src = nodes[src_name] = pydot.Node(src_name, label=src_label)
+            src = nodes[src_name] = pydot.Node(src_name,
+                    label       = src_label,
+                    fontsize    = 18,
+            )
             dot.add_node(src)
         
         # dst
@@ -205,17 +208,21 @@
         if dst_name in nodes :
             dst = nodes[dst_name]
         else :
-            dst = nodes[dst_name] = pydot.Node(dst_name, label=dst_label)
+            dst = nodes[dst_name] = pydot.Node(dst_name,
+                    label       = dst_label,
+                    fontsize    = 18,
+            )
             dot.add_node(dst)
 
         # edges
         headlabel = '"{remote[port]}"'.format(remote=remote)
         taillabel = '"{local[port]}"'.format(local=local)
-        fillcolor = None
-        color = None
+        fillcolor = 'black'
+        color = 'black'
+        untag = tagged = None
 
         # vlans?
-        if host in vlans and local['port_id'] in vlans[host] :
+        if vlans and host in vlans and local['port_id'] in vlans[host] :
             untag, tagged = vlans[host][local['port_id']]
             
             log.debug("%s#%s: %s+%s", host, local['port_id'], untag, tagged)
@@ -248,27 +255,17 @@
                 fillcolor = vlan_colors[tag] = color
             
             # first color overrides fillcolor for heads
-            if colors and fillcolor :
+            if colors and untag :
                 color = ':'.join([fillcolor] + colors)
             elif colors :
                 color = ':'.join(colors)
             elif fillcolor :
                 color = fillcolor
-            else :
-                color = 'black'
-
-            if not fillcolor :
-                fillcolor = 'black'
 
         elif vlans :
             # XXX: this happens when LLDP gives us the LACP ports but the VLANS are on the TRK port
             log.warn("%s#%s: unknown port for vlans: %s", host, local['port_id'], vlans.get(host))
 
-            untag = tag = None
-
-        else :
-            untag = tag = None
-
         # edge
         if (src_name, local['port'], dst_name, remote['port']) in edges :
             log.warning("%s:%s <- %s:%s: duplicate", src_name, local['port'], dst_name, remote['port'])
@@ -286,7 +283,7 @@
             if edge.get('fillcolor') != fillcolor :
                 log.warn("%s#%s -> %s#%s: remote untag mismatch: %s vs %s", src_name, local['port'], dst_name, remote['port'], fillcolor, edge.get('fillcolor'))
 
-            if edge.get('color') != '"' + (color or 'black') + '"' :
+            if edge.get('color') != '"' + color + '"' :
                 log.warn("%s#%s -> %s#%s: remote tagged mismatch: %s vs %s", src_name, local['port'], dst_name, remote['port'], color, edge.get('color'))
 
             # mark as bidirectional
@@ -307,8 +304,8 @@
                     dir         = 'forward' if untag else 'none',
                     headlabel   = headlabel,
                     taillabel   = taillabel,
-                    color       = '"{color}"'.format(color=color) if color else 'black',
-                    fillcolor   = fillcolor or 'black',
+                    color       = '"{color}"'.format(color=color),
+                    fillcolor   = fillcolor,
             )
 
             dot.add_edge(edge)
@@ -329,6 +326,9 @@
     parser.add_option('--graph-dot',
             help="Output .dot graph data")
 
+    parser.add_option('--no-vlans', action='store_const', dest='vlans', const=False,
+            help="Do not color VLANs")
+
     # input
     options, args = parser.parse_args(argv[1:])
     pvl.args.apply(options)
@@ -336,7 +336,10 @@
     hosts = pvl.hosts.apply(options, args)
     
     # lookup host-port-vlan mappings
-    vlans = dict(apply_hosts_vlan(options, hosts))
+    if options.vlans is False :
+        vlans = None
+    else :
+        vlans = dict(apply_hosts_vlan(options, hosts))
 
     # discover node/port graph
     items = apply_hosts_lldp(options, hosts)