Add comment

Author: bbeaudreault

hbase-client/src/main/java/org/apache/hadoop/hbase/client/ConnectionManager.java

@@ -1286,6 +1286,10 @@ private RegionLocations locateRegionInMeta(TableName tableName, byte[] row,
       Scan s = new Scan();
       s.setReversed(true);
       s.withStartRow(metaKey);
+
+      // Adding a filter on CATALOG_FAMILY is necessary for compatibility
+      // with hbase 2.x and beyond, which adds additional column families.
+      // See HBASE-26797
       s.addFamily(HConstants.CATALOG_FAMILY);
 
       if (this.useMetaReplicas) {

hbase-client/src/main/java/org/apache/hadoop/hbase/client/MetaScanner.java

@@ -220,6 +220,9 @@ private static Result getClosestRowOrBefore(final Table metaTable, final TableNa
   throws IOException {
     byte[] searchRow = HRegionInfo.createRegionName(userTableName, row, HConstants.NINES, false);
     Scan scan = Scan.createGetClosestRowOrBeforeReverseScan(searchRow);
+    // Adding a filter on CATALOG_FAMILY is necessary for compatibility
+    // with hbase 2.x and beyond, which adds additional column families.
+    // See HBASE-26797
     scan.addFamily(HConstants.CATALOG_FAMILY);
     if (useMetaReplicas) {
       scan.setConsistency(Consistency.TIMELINE);