Merge pull request #4786 from r-vasquez/odd-replica-factor-text

rpk: improve wording in topic create: replication factor must be odd

src/go/rpk/pkg/cli/cmd/topic/create.go

@@ -103,6 +103,8 @@ the cleanup.policy=compact config option set.
 				if err := kerr.ErrorForCode(topic.ErrorCode); err != nil {
 					if errors.Is(err, kerr.InvalidPartitions) && partitions > 0 {
 						msg = fmt.Sprintf("INVALID_PARTITIONS: unable to create topic with %d partitions due to hardware constraints", partitions)
+					} else if errors.Is(err, kerr.InvalidReplicationFactor) && replicas%2 == 0 {
+						msg = "INVALID_REPLICATION_FACTOR: replication factor must be odd"
 					} else {
 						msg = err.Error()
 					}
@@ -114,7 +116,7 @@ the cleanup.policy=compact config option set.
 	}
 	cmd.Flags().StringArrayVarP(&configKVs, "topic-config", "c", nil, "key=value; Config parameters (repeatable; e.g. -c cleanup.policy=compact)")
 	cmd.Flags().Int32VarP(&partitions, "partitions", "p", 1, "Number of partitions to create per topic")
-	cmd.Flags().Int16VarP(&replicas, "replicas", "r", -1, "Replication factor; if -1, this will be the broker's default.replication.factor")
+	cmd.Flags().Int16VarP(&replicas, "replicas", "r", -1, "Replication factor (must be odd); if -1, this will be the broker's default.replication.factor")
 	cmd.Flags().BoolVarP(&dry, "dry", "d", false, "dry run: validate the topic creation request; do not create topics")
 
 	// Sept 2021