From 8a6913fe19f246deeaaa9de22e5adccb1cd4a981 Mon Sep 17 00:00:00 2001
From: John Anderson <lampwins@gmail.com>
Date: Mon, 12 Nov 2018 23:18:23 -0500
Subject: [PATCH] fixed #2585 - connections with virtual interfaces

---
 netbox/dcim/models.py | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/netbox/dcim/models.py b/netbox/dcim/models.py
index 9a0a59bb8..501bf32cb 100644
--- a/netbox/dcim/models.py
+++ b/netbox/dcim/models.py
@@ -2553,6 +2553,20 @@ class Cable(ChangeLoggedModel):
                 self.termination_b, self.termination_b.cable_id
             ))
 
+        # Virtual interfaces cannot be connected
+        endpoint_a, endpoint_b = self.get_path_endpoints()
+        if (
+            (
+                isinstance(endpoint_a, Interface) and
+                endpoint_a.form_factor == IFACE_FF_VIRTUAL
+            ) or
+            (
+                isinstance(endpoint_b, Interface) and
+                endpoint_b.form_factor == IFACE_FF_VIRTUAL
+            )
+        ):
+            raise ValidationError("Cannot connect to a virtual interface")
+
         # Validate length and length_unit
         if self.length and not self.length_unit:
             raise ValidationError("Must specify a unit when setting a cable length")