--- a/bin/pvl.hosts-graph	Sun Mar 30 14:21:57 2014 +0300
+++ b/bin/pvl.hosts-graph	Mon Mar 31 14:27:39 2014 +0300
@@ -169,8 +169,10 @@
             { (remote, remote_port, local_port, local): (local_untag, tagged, remote_untag) }
     """
 
-    nodes = { }
+    nodes = { } # host: label
     links = { }
+
+    hosts_by_lldp = { }
     
     # first scan: lldp hosts
     for host, host_attrs in snmp.iteritems() :
@@ -178,8 +180,10 @@
 
         if lldp :
             lldp_local = lldp['local']
+            local = lldp_local['chassis']
             
-            nodes[lldp_local['chassis']] = host.location
+            nodes[host] = host.location
+            hosts_by_lldp[local] = host
     
     # second scan: lldp remotes
     for host, host_attrs in snmp.iteritems() :
@@ -189,6 +193,7 @@
             continue
 
         local = lldp['local']['chassis']
+        local_node = host
 
         if 'vlan' in host_attrs :
             vlans = dict(host_vlans(host, host_attrs['vlan']))
@@ -199,8 +204,13 @@
             local_port = port_attrs['local']['port']
 
             for remote, remote_attrs in port_attrs['remote'].iteritems() :
-                if remote not in nodes :
-                    nodes[remote] = remote_attrs['sys_name']
+                if remote in hosts_by_lldp :
+                    remote_node = hosts_by_lldp[remote]
+                else :
+                    remote_node = remote
+
+                    # non-snmp lldp host
+                    nodes[remote_node] = remote_attrs['sys_name']
 
                 remote_port = remote_attrs['port']
                 
@@ -214,8 +224,8 @@
                     local_untag, local_tagged = port_vlans
                 
                 # bidirectional mappings
-                forward = (local, local_port, remote_port, remote)
-                reverse = (remote, remote_port, local_port, local)
+                forward = (local_node, local_port, remote_port, remote_node)
+                reverse = (remote_node, remote_port, local_port, local_node)
 
                 if reverse not in links :
                     links[forward] = (local_untag, local_tagged, None)
@@ -225,14 +235,14 @@
                     # merge
                     if remote_untag != local_untag :
                         log.warning("%s:%s untag %s <=> %s untag %s:%s",
-                                nodes[local], local_port, local_untag,
-                                remote_untag, nodes[remote], remote_port
+                                host, local_port, local_untag,
+                                remote_untag, remote_node, remote_port
                         )
 
                     if remote_tagged != local_tagged :
                         log.warning("%s:%s tagged %s <-> %s tagged %s:%s",
-                                nodes[local], local_port, ':'.join(str(x) for x in sorted(local_tagged)),
-                                ':'.join(str(x) for x in sorted(remote_tagged)), nodes[remote], remote_port
+                                host, local_port, ':'.join(str(x) for x in sorted(local_tagged)),
+                                ':'.join(str(x) for x in sorted(remote_tagged)), remote_node, remote_port
                         )
 
                     links[reverse] = (remote_untag, remote_tagged, local_untag)