From f0cb17f4cb882ee76f2d35eaa8ce0496c1848470 Mon Sep 17 00:00:00 2001
From: Hans Hasselberg <me@hans.io>
Date: Thu, 29 Aug 2019 10:22:51 +0200
Subject: [PATCH] do not surface left servers in catalog

---
 agent/metadata/server.go | 4 ++++
 agent/router/router.go   | 6 ++++++
 2 files changed, 10 insertions(+)

diff --git a/agent/metadata/server.go b/agent/metadata/server.go
index 2532fa3bfa9b..15035c3c4507 100644
--- a/agent/metadata/server.go
+++ b/agent/metadata/server.go
@@ -64,6 +64,10 @@ func (s *Server) String() string {
 	return fmt.Sprintf("%s (Addr: %s/%s) (DC: %s)", s.Name, networkStr, addrStr, s.Datacenter)
 }
 
+func (s *Server) HasLeft() bool {
+	return s.Status == serf.StatusLeft
+}
+
 var versionFormat = regexp.MustCompile(`\d+\.\d+\.\d+`)
 
 // IsConsulServer returns true if a serf member is a consul server
diff --git a/agent/router/router.go b/agent/router/router.go
index 426ca1628389..d723b4506aea 100644
--- a/agent/router/router.go
+++ b/agent/router/router.go
@@ -406,6 +406,12 @@ func (r *Router) GetDatacentersByDistance() ([]string, error) {
 				continue
 			}
 
+			if parts.HasLeft() {
+				r.logger.Printf("[DEBUG]: consul: server %q in area %q left, skipping",
+					m.Name, areaID)
+				continue
+			}
+
 			existing := index[parts.Datacenter]
 			if parts.Datacenter == r.localDatacenter {
 				// Everything in the local datacenter looks like zero RTT.