From ed0a74216188d035286c18e0c70e87128b171f88 Mon Sep 17 00:00:00 2001
From: Sean Busbey <busbey@apache.org>
Date: Tue, 17 Sep 2019 22:47:17 -0500
Subject: [PATCH] HBASE-23040 give friendly message about unknown server when
 running unload for RegionMover.

---
 .../main/java/org/apache/hadoop/hbase/util/RegionMover.java  | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java
index fdd079e1348c..87391ade6321 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java
@@ -421,6 +421,11 @@ public boolean unload() throws InterruptedException, ExecutionException, Timeout
                 .keySet());
         // Remove the host Region server from target Region Servers list
         ServerName server = stripServer(regionServers, hostname, port);
+        if (server == null) {
+          LOG.info("Could not find server '{}:{}' in the set of region servers. giving up.", hostname, port);
+          LOG.debug("List of region servers: {}", regionServers);
+          return false;
+        }
         // Remove RS present in the exclude file
         stripExcludes(regionServers);
         stripMaster(regionServers);