From 29cb32539e67f45f9bd2cfa19042a94266414f3e Mon Sep 17 00:00:00 2001
From: dHannasch <David.A.Hannasch@gmail.com>
Date: Tue, 10 Nov 2020 19:22:10 -0700
Subject: [PATCH] [Core] If failed to connect to redis, try to say why.
 (#11916)

---
 src/ray/gcs/redis_context.cc | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/ray/gcs/redis_context.cc b/src/ray/gcs/redis_context.cc
index 8f6a157ef..f4efa423f 100644
--- a/src/ray/gcs/redis_context.cc
+++ b/src/ray/gcs/redis_context.cc
@@ -301,7 +301,14 @@ Status ConnectWithRetries(const std::string &address, int port,
       }
       break;
     }
-    RAY_LOG(WARNING) << "Failed to connect to Redis, retrying.";
+    if (*context == nullptr) {
+      RAY_LOG(WARNING) << "Could not allocate Redis context, retrying.";
+    }
+    if ((*context)->err) {
+      RAY_LOG(WARNING) << "Could not establish connection to Redis " << address << ":"
+                       << port << " (context.err = " << (*context)->err << ")"
+                       << ", retrying.";
+    }
     // Sleep for a little.
     std::this_thread::sleep_for(std::chrono::milliseconds(
         RayConfig::instance().redis_db_connect_wait_milliseconds()));