ERROR MY-011542 Repl Plugin group_replication reported: 'Table repl_test does not have any PRIMARY KEY - innodb

Question

I installed an InnoDB Cluster recently and trying to create a table without any primary key or equivalent to test the cluster index concept where "InnoDB internally generates a hidden clustered index named GEN_CLUST_INDEX on a synthetic column containing row ID values if the table has no PRIMARY KEY or suitable UNIQUE index".
I created table as below:
create table repl_test (Name varchar(10));
Checked for the creation of GEN_CLUST_INDEX:
select * from mysql.innodb_index_stats where database_name='test' and table_name = 'repl_test';
+---------------+------------+-----------------+---------------------+--------------+------------+-------------+-----------------------------------+
| database_name | table_name | index_name | last_update | stat_name | stat_value | sample_size | stat_description |
+---------------+------------+-----------------+---------------------+--------------+------------+-------------+-----------------------------------+
| test | repl_test | GEN_CLUST_INDEX | 2019-02-22 06:29:26 | n_diff_pfx01 | 0 | 1 | DB_ROW_ID |
| test | repl_test | GEN_CLUST_INDEX | 2019-02-22 06:29:26 | n_leaf_pages | 1 | NULL | Number of leaf pages in the index |
| test | repl_test | GEN_CLUST_INDEX | 2019-02-22 06:29:26 | size | 1 | NULL | Number of pages in the index |
+---------------+------------+-----------------+---------------------+--------------+------------+-------------+-----------------------------------+
3 rows in set (0.00 sec)
But, when I try to insert row, I get the below error:
insert into repl_test values ('John');
ERROR 3098 (HY000): The table does not comply with the requirements by an external plugin.
2019-02-22T14:32:53.177700Z 594022 [ERROR] [MY-011542] [Repl] Plugin group_replication reported: 'Table repl_test does not have any PRIMARY KEY. This is not compatible with Group Replication.'
Below is my conf file:
[client]
port = 3306
socket = /tmp/mysql.sock
[mysqld_safe]
socket = /tmp/mysql.sock
[mysqld]
socket = /tmp/mysql.sock
port = 3306
basedir = /mysql/product/8.0/TEST
datadir = /mysql/data/TEST/innodb_data
log-error = /mysql/admin/TEST/innodb_logs/mysql.log
log_bin = /mysql/binlog/TEST/innodb_logs/mysql-bin
server-id=1
max_connections = 500
open_files_limit = 65535
expire_logs_days = 15
innodb_flush_log_at_trx_commit=1
sync_binlog=1
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
binlog_checksum = NONE
enforce_gtid_consistency = ON
gtid_mode = ON
relay-log=<<hostname>>-relay-bin
My MySQL version: mysql Ver 8.0.11 for linux-glibc2.12 on x86_64 (MySQL Community Server - GPL)

Answer 1

Auto-generation of the PK should work fine for non-clustered setups. However, InnoDB Cluster (Group Replication) and Galera need a user PK (or UNIQUE that can be promoted).
If you like, file a documentation bug with bugs.mysql.com complaining that this restriction is not clear. Be sure to point to the page that needs fixing.