From 69f3ceeb7ccacdc1dfb6293869093b8d6d9669e2 Mon Sep 17 00:00:00 2001
From: Brad Fitzpatrick <bradfitz@tailscale.com>
Date: Mon, 27 Jul 2020 10:10:10 -0700
Subject: [PATCH] derp/derphttp: don't return all nil from dialRegion when
 STUNOnly nodes

---
 derp/derphttp/derphttp_client.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/derp/derphttp/derphttp_client.go b/derp/derphttp/derphttp_client.go
index 946c8c937..83697c257 100644
--- a/derp/derphttp/derphttp_client.go
+++ b/derp/derphttp/derphttp_client.go
@@ -338,6 +338,9 @@ func (c *Client) dialRegion(ctx context.Context, reg *tailcfg.DERPRegion) (net.C
 	var firstErr error
 	for _, n := range reg.Nodes {
 		if n.STUNOnly {
+			if firstErr == nil {
+				firstErr = fmt.Errorf("no non-STUNOnly nodes for %s", c.targetString(reg))
+			}
 			continue
 		}
 		c, err := c.dialNode(ctx, n)